AR Sponsor
HICAR - High Pressure 82kpsi M855A1+ rifle for SOCOM (Page 3 of 5)
Joined:
Apr 2023
Posts:
321
EE: 100% (4)
FL, USA
Joined:
Mar 2022
Posts:
18
EE: 100% (4)
USA
|
Originally Posted By spydercomonkey: To give a sense of the limiting effect of the 2.25" COL, and the drag of the M855A1 projectile shape, I ran the numbers through Berger: https://bergerbullets.com/ballistics-calculator/ M855A1 = G7 BC 0.152 (common number I've seen citied online) 11.5" regular velocity ~ 2750fps 11.5" High Pressure ~ 3150fps Goal was turning current '300m effectiveness' into '600m effectiveness'--> 11.5" regular = 1836fps @ 300m 11.5" HP = 1836fps @ 420m Without a lower drag projectile shape, the +400fps only leads to modest gains in range. By comparison: 5.45 7n6 53gr G7 bc 0.168 @ 2950fps (basic 70's AK74) 1836fps @ 402m So the worlds most advanced AR15 with state of the art high pressure ammo will only modestly outrange the AK74, simply because the 5.45 has a modestly lower drag projectile  Here's a quote directly from the RFP: "White papers should include information on how the vendor’s proposal is specifically optimized to function with current hypervelocity ammunition as well as engineered to accommodate future ammunition in excess of 82kpsi." Just some food for thought, the Peak Alloy cases (and in fairness the Sig cases too) have been tested beyond 100k PSI for DoD. The numbers I cited in an earlier post were at lower pressures. Some high pressure offerings are much harder on guns than others. As powders and projectiles continue to evolve, so will the weapon tech to handle it. Rifling geometry, materials, bolt design, etc...some manufacturers are more ahead of the curve than others. |
|
Increasing pressure in a small diameter cartridge is an exercise in minimal returns. Increasing bore diameter even slightly starts making things a lot more efficient. More surface area for that pressure to operate against. Especially in a shorter barrel where there isn't much time for that pressure to be pushing. Short barrel 5.56s aren't efficient anyway and increasing pressure is just blowing more noise and flash out the front with minimal gain in performance. Going up to a 6mm/.25/6.5mm/6.8mm bullet could get them the improvement they are looking for with minimal to no increase in pressure, just a little bump in case capacity. Maybe the 6.8spc wasn't that bad of an idea after all. Necking it down to 25 or 6.5 would give them better long-range external ballistics. The 1970's Brits said 25 was ideal. I think somewhere in the range of 25 to 6.8mm in an SPC case as they determined over 20 years ago would be a much better idea than issuing 5.56 proof loads. Originally Posted By medieval_flail: Just to illustrate how thin 6 ARC bolt are. I assume the ICAR is built around 6 ARC from the ground up as an intermediate frame. https://i.imgur.com/ksp7OhD.jpeg Main reason I'm not a fan of that case size in the AR15. |
This is...a clue - Pat_Rogers
I'm not adequately aluminumized for this thread. - gonzo_beyondo
CO, MI, OR - Please lobby your legislators to end discrimination against non-resident CCW permit holders
I'm not adequately aluminumized for this thread. - gonzo_beyondo
CO, MI, OR - Please lobby your legislators to end discrimination against non-resident CCW permit holders
|
Originally Posted By Gamma762: Increasing pressure in a small diameter cartridge is an exercise in minimal returns. Increasing bore diameter even slightly starts making things a lot more efficient. More surface area for that pressure to operate against. Especially in a shorter barrel where there isn't much time for that pressure to be pushing. Short barrel 5.56s aren't efficient anyway and increasing pressure is just blowing more noise and flash out the front with minimal gain in performance. Going up to a 6mm/.25/6.5mm/6.8mm bullet could get them the improvement they are looking for with minimal to no increase in pressure, just a little bump in case capacity. Maybe the 6.8spc wasn't that bad of an idea after all. Necking it down to 25 or 6.5 would give them better long-range external ballistics. The 1970's Brits said 25 was ideal. I think somewhere in the range of 25 to 6.8mm in an SPC case as they determined over 20 years ago would be a much better idea than issuing 5.56 proof loads. Main reason I'm not a fan of that case size in the AR15. Originally Posted By Gamma762: Increasing pressure in a small diameter cartridge is an exercise in minimal returns. Increasing bore diameter even slightly starts making things a lot more efficient. More surface area for that pressure to operate against. Especially in a shorter barrel where there isn't much time for that pressure to be pushing. Short barrel 5.56s aren't efficient anyway and increasing pressure is just blowing more noise and flash out the front with minimal gain in performance. Going up to a 6mm/.25/6.5mm/6.8mm bullet could get them the improvement they are looking for with minimal to no increase in pressure, just a little bump in case capacity. Maybe the 6.8spc wasn't that bad of an idea after all. Necking it down to 25 or 6.5 would give them better long-range external ballistics. The 1970's Brits said 25 was ideal. I think somewhere in the range of 25 to 6.8mm in an SPC case as they determined over 20 years ago would be a much better idea than issuing 5.56 proof loads. Originally Posted By medieval_flail: Just to illustrate how thin 6 ARC bolt are. I assume the ICAR is built around 6 ARC from the ground up as an intermediate frame. https://i.imgur.com/ksp7OhD.jpeg Main reason I'm not a fan of that case size in the AR15. They're trying to maintain ammo comparability w/ their host nation but get some of the range gains from the Army's new Pattern 13. |
I sell firearms produced by the finest child labor in the world, be it Filipino, Muslim, Mormon, Arizonan, or Texan.
|
Originally Posted By TMS4311: Here's a quote directly from the RFP: "White papers should include information on how the vendor’s proposal is specifically optimized to function with current hypervelocity ammunition as well as engineered to accommodate future ammunition in excess of 82kpsi." Just some food for thought, the Peak Alloy cases (and in fairness the Sig cases too) have been tested beyond 100k PSI for DoD. The numbers I cited in an earlier post were at lower pressures. Some high pressure offerings are much harder on guns than others. As powders and projectiles continue to evolve, so will the weapon tech to handle it. Rifling geometry, materials, bolt design, etc...some manufacturers are more ahead of the curve than others. Originally Posted By TMS4311: Originally Posted By spydercomonkey: To give a sense of the limiting effect of the 2.25" COL, and the drag of the M855A1 projectile shape, I ran the numbers through Berger: https://bergerbullets.com/ballistics-calculator/ M855A1 = G7 BC 0.152 (common number I've seen citied online) 11.5" regular velocity ~ 2750fps 11.5" High Pressure ~ 3150fps Goal was turning current '300m effectiveness' into '600m effectiveness'--> 11.5" regular = 1836fps @ 300m 11.5" HP = 1836fps @ 420m Without a lower drag projectile shape, the +400fps only leads to modest gains in range. By comparison: 5.45 7n6 53gr G7 bc 0.168 @ 2950fps (basic 70's AK74) 1836fps @ 402m So the worlds most advanced AR15 with state of the art high pressure ammo will only modestly outrange the AK74, simply because the 5.45 has a modestly lower drag projectile Here's a quote directly from the RFP: "White papers should include information on how the vendor’s proposal is specifically optimized to function with current hypervelocity ammunition as well as engineered to accommodate future ammunition in excess of 82kpsi." Just some food for thought, the Peak Alloy cases (and in fairness the Sig cases too) have been tested beyond 100k PSI for DoD. The numbers I cited in an earlier post were at lower pressures. Some high pressure offerings are much harder on guns than others. As powders and projectiles continue to evolve, so will the weapon tech to handle it. Rifling geometry, materials, bolt design, etc...some manufacturers are more ahead of the curve than others. The problem really is the limited COL of the AR15 magwell, you just cant have the long pointy nose bullets you need to take advantage of the extra velocity. 11.5" M855A1 2750fps = 1836fps @ 300m 11.5" M855A1 100kpsi 3400fps ="" @ 485m This is not much better then the 82kpsi 420m range, despite the extreme velocity. In this wonderful TFB article (back when they did high effort posts) the author models various EPR style projectiles (like M855A1) in a VLD Low Drag shape. https://www.thefirearmblog.com/blog/2017/09/09/romulan-vulcan-preference-driven-vs-process-driven-design-field-small-arms-ammunition/ His .224 66gr VLD = 0.211 G7 2750fps = 1836fps @ 420m So a slightly longer and pointier projectile at 62kpsi nearly equals the performance of M855A1 at 82kpsi, and isn't that much behind the 100kpsi. If this projectile was paired with high pressure, the results become outrageous: 3150fps = 1836fps @ 580m 3400fps = 1836fps @ 676m It's maddening because we're talking less than a 1/4" of length difference between marginal and magical. 
|
|
Originally Posted By Gamma762: Increasing pressure in a small diameter cartridge is an exercise in minimal returns. Increasing bore diameter even slightly starts making things a lot more efficient. More surface area for that pressure to operate against. Especially in a shorter barrel where there isn't much time for that pressure to be pushing. Short barrel 5.56s aren't efficient anyway and increasing pressure is just blowing more noise and flash out the front with minimal gain in performance. This is correct for muzzle velocity / muzzle energy. Thats the principle SABOTs work under. But it's the opposite of what you want for low drag projectiles if you are limited to a fixed magwell length. Basically a Very Low Drag (VLD) projectile has a Length/Diameter (L/D) ratio of around 5-5.5. And much of that length needs to be in the pointy nosecone area that extends outside the cartridge case. If you were trying to maximize long range velocity retention within the 2.25" limit of the AR15, the move would be going with a narrower diameter .204/5mm VLD, so you could have the L/D ratio of 5-5.5 without the bullet being too long. 5.56 necked down to 5mm, low drag bullet 50gr .204 G7 0.192 @ 3100fps = 1836fps @ 512m To achieve that with a wider and therefore longer projectile requires shortening and fattening the case, as was done with 6.5 Grendel and 6.8 SPC. But this then resulted in weaker bolts and lowering of pressure, as well as dubious mag reliability and reduced capacity. |
|
Originally Posted By medieval_flail: Just to illustrate how thin 6 ARC bolt are. I assume the ICAR is built around 6 ARC from the ground up as an intermediate frame. https://i.imgur.com/ksp7OhD.jpeg It seems like ICAR may actually be built not just for 6 ARC, but for High Pressure 6mm ARC. Like going from the current lame 52kpsi to 80-100kpsi.... Here the video mentions that he fired the ICAR launching 108gr @ 3100fps from a 18", which is cookoo bananas speed.  Should begin 15:09 https://www.youtube.com/watch?si=XLC56qVVClSrSNbr&t=909&v=lF47B1otpvM&feature=youtu.be This high pressure pedigree is also why I think the new HICAR will be a 5.56 version of the ICAR. |
Member
Joined:
Dec 2023
Posts:
10124
EE: 100% (7)
USA
|
Originally Posted By AK-12: Yes. They shoot the old ART (now called ERT-Entry Level Training) qual at boot camp, and their annual rifle qual thereafter is the ARQ. ARQ allows you to use your pack as a rest, or use a bipod. Most Marines seem to prefer using a grip pod. ARQ isn't perfect, but from a "gunfighter" perspective it's a substantial improvement over the old ART course of fire because it features barricades and positional shooting. What it lacks is primarily that it doesn't teach marksmanship fundamentals, which is why they still shoot ERT at boot camp. We need to be cautious about how broadly we apply lessons from the war in Ukraine to our expectations of future conflict. My biggest issue with what the Army is attempting to do with these new weapon systems is that they're "modernizing" the wrong equipment, which seems to indicate that their expectations are for small arms gunfights to determine success or failure. Infantry needs to be viewed as a maneuver capability, to supplement or be supplemented by fires, armor, etc... What they should be doing is making it easier for infantry formations to maneuver. Over the past few decades we've significantly encumbered them with armor, batteries, and all sorts of other things that make maneuver more difficult. One of the reasons the M4/AR is becoming even more prolific than it already was even after being in service for 50+ years is that it does everything an infantry rifle needs to do while also being very light. With these new small arms solicitations the Army seems to want weapons that do things an infantry rifle doesn't need to do at the expense of doubling the weight and reducing durability. We are still issuing bulky ICW body armor with soft inserts that become less effective when they get wet. Our new light family of vehicles is triple the weight of what it replaced, and somehow less reliable. We are spending a lot of money in the wrong areas IMHO. Hence my thoughts that improved 40mm and indirect fire options would be a better investment, nevermind lightweight, reliable, and inexpensive vehicles or armored weapons platforms that could be air dropped. |
|
Originally Posted By spydercomonkey: It seems like ICAR may actually be built not just for 6 ARC, but for High Pressure 6mm ARC. Like going from the current lame 52kpsi to 80-100kpsi.... Here the video mentions that he fired the ICAR launching 108gr @ 3100fps from a 18", which is cookoo bananas speed. Should begin 15:09 https://www.youtube.com/watch?si=XLC56qVVClSrSNbr&t=909&v=lF47B1otpvM&feature=youtu.be This high pressure pedigree is also why I think the new HICAR will be a 5.56 version of the ICAR. The big limitation is that the URG has to be compatible with existing M4/M16 receivers. ICAR uses a different magwell length, etc. The thing to remember is that - in the words of the SOF Lethality PM - this is basically a science project. They are trying to see if 5.56mm high pressure is even really feasible with that restriction before they commit to funding development of a whole new system. ICAR is fantastic because they were allowed to break the mold that everyone else was trying to fit. Until the uppers are submitted and tested, we won't have scientific validation that the concept works or doesn't. We then have to hope and pray that they make the right decision on how to move forward with those results. |
|
Originally Posted By AK-12: My biggest issue with what the Army is attempting to do with these new weapon systems is that they're "modernizing" the wrong equipment, which seems to indicate that their expectations are for small arms gunfights to determine success or failure. What has the Army been doing for the last 20 years? Ain't been maneuver warfare w/ armor & air assaults. It's been FOBs & small arms engagements - for the entirely of most officer's careers. You always prepare to win the last war. |
I sell firearms produced by the finest child labor in the world, be it Filipino, Muslim, Mormon, Arizonan, or Texan.
|
Originally Posted By backbencher: What has the Army been doing for the last 20 years? Ain't been maneuver warfare w/ armor & air assaults. It's been FOBs & small arms engagements - for the entirely of most officer's careers. You always prepare to win the last war. Nothing against GWOT vets (I am one), but they tend to get entirely too gassed up on conflicts that largely consisted of taking potshots at cavemen. |
|
Originally Posted By AK-12: Nothing against GWOT vets (I am one), but they tend to get entirely too gassed up on conflicts that largely consisted of taking potshots at cavemen. Originally Posted By AK-12: Originally Posted By backbencher: What has the Army been doing for the last 20 years? Ain't been maneuver warfare w/ armor & air assaults. It's been FOBs & small arms engagements - for the entirely of most officer's careers. You always prepare to win the last war. Nothing against GWOT vets (I am one), but they tend to get entirely too gassed up on conflicts that largely consisted of taking potshots at cavemen. You know what you know. If all your experience is small arms engagements from light armored vehicles and operating from FOBs, then you want the best light armored vehicles and small arms you can get. Drones, anti-tank, eh? We didn't use that stuff, what we have now is fine. But we need a better MRAP & rifle. If all your experience is trench warfare & falling back at most 5 miles on French territory for 4 years as the Germans attack, when you're in Belgium a mere 20 years later and the Germans attack, eh, retreat 5 miles, we'll try again tomorrow... |
I sell firearms produced by the finest child labor in the world, be it Filipino, Muslim, Mormon, Arizonan, or Texan.
|
Originally Posted By rb889: Hence my thoughts that improved 40mm and indirect fire options would be a better investment, nevermind lightweight, reliable, and inexpensive vehicles or armored weapons platforms that could be air dropped. The Army is pursuing this with the new Precision Grenadier System (PGS), which will be a semi auto high velocity grenade launcher. Candidates are 25-30mm, as well as the 40mm Medium velocity by Rheinmetall. https://www.nationaldefensemagazine.org/articles/2026/1/23/army-looks-beyond-defilade-for-precision-grenadier-weapon  The Marines seem to plan to make the Carl Gustaf a Squad asset, equipped with a nasty 84mm airburst round with ~2000 tungsten BB's. https://www.defenceprocurementinternational.com/news/land/saab-recently-showcased-its-new-he-448-programmable-munition-for-the-carl-gustaf  That said, I expect a sort of autonomous / semi autonomous 'flying claymore' drone will make these obsolete within then the next 5 years. Already a piloted version now: https://www.kyivpost.com/post/46368 
|
|
Originally Posted By ELittlefield: I suppose that's the next step that will have to be taken. Time will tell if it's a good idea. I'd really love 3000 fps out of a suppressed 10.5. Not a great projectile, but these Shell Shock commercialy available loads are hitting 2900fps+ from a 10.5" https://badlandsmunitionsco.com/product/5-56-s-s-55gr-193-ammo/ 
|
|
Originally Posted By PacificNic: The big limitation is that the URG has to be compatible with existing M4/M16 receivers. ICAR uses a different magwell length, etc. The thing to remember is that - in the words of the SOF Lethality PM - this is basically a science project. They are trying to see if 5.56mm high pressure is even really feasible with that restriction before they commit to funding development of a whole new system. ICAR is fantastic because they were allowed to break the mold that everyone else was trying to fit. Until the uppers are submitted and tested, we won't have scientific validation that the concept works or doesn't. We then have to hope and pray that they make the right decision on how to move forward with those results. Originally Posted By PacificNic: Originally Posted By spydercomonkey: It seems like ICAR may actually be built not just for 6 ARC, but for High Pressure 6mm ARC. Like going from the current lame 52kpsi to 80-100kpsi.... Here the video mentions that he fired the ICAR launching 108gr @ 3100fps from a 18", which is cookoo bananas speed. Should begin 15:09 https://www.youtube.com/watch?si=XLC56qVVClSrSNbr&t=909&v=lF47B1otpvM&feature=youtu.be This high pressure pedigree is also why I think the new HICAR will be a 5.56 version of the ICAR. The big limitation is that the URG has to be compatible with existing M4/M16 receivers. ICAR uses a different magwell length, etc. The thing to remember is that - in the words of the SOF Lethality PM - this is basically a science project. They are trying to see if 5.56mm high pressure is even really feasible with that restriction before they commit to funding development of a whole new system. ICAR is fantastic because they were allowed to break the mold that everyone else was trying to fit. Until the uppers are submitted and tested, we won't have scientific validation that the concept works or doesn't. We then have to hope and pray that they make the right decision on how to move forward with those results. It does make you wonder what we could be seeing if the M16 had been originally designed with a longer COAL in mind. |
|
Originally Posted By doubleclaw: I watched in tooth-grinding rage as a USAR MED DET of a hundred "soldiers" took four days (!) to finish on the 25m range at Fort Wolters. No amount of remedial training will work on people who simply don't give a fuck. Any medical detachment should be required to read about Cpt. Ben Salomon before they qualify. If they show a lack of tiddlywink spirit after that, then they should all be given remedial physical training until they all vomit. |
|
Originally Posted By rb889: It does make you wonder what we could be seeing if the M16 had been originally designed with a longer COAL in mind. Originally Posted By rb889: Originally Posted By PacificNic: Originally Posted By spydercomonkey: It seems like ICAR may actually be built not just for 6 ARC, but for High Pressure 6mm ARC. Like going from the current lame 52kpsi to 80-100kpsi.... Here the video mentions that he fired the ICAR launching 108gr @ 3100fps from a 18", which is cookoo bananas speed. Should begin 15:09 https://www.youtube.com/watch?si=XLC56qVVClSrSNbr&t=909&v=lF47B1otpvM&feature=youtu.be This high pressure pedigree is also why I think the new HICAR will be a 5.56 version of the ICAR. The big limitation is that the URG has to be compatible with existing M4/M16 receivers. ICAR uses a different magwell length, etc. The thing to remember is that - in the words of the SOF Lethality PM - this is basically a science project. They are trying to see if 5.56mm high pressure is even really feasible with that restriction before they commit to funding development of a whole new system. ICAR is fantastic because they were allowed to break the mold that everyone else was trying to fit. Until the uppers are submitted and tested, we won't have scientific validation that the concept works or doesn't. We then have to hope and pray that they make the right decision on how to move forward with those results. It does make you wonder what we could be seeing if the M16 had been originally designed with a longer COAL in mind. It was designed with .222 Remington in mind, then someone added helmet penetration at distance, so we got the .222 Remington Special. The AR-15 was to be as small and light as possible, and the magwell length determines a measurable part of the mass of the receivers. |
I sell firearms produced by the finest child labor in the world, be it Filipino, Muslim, Mormon, Arizonan, or Texan.
|
Originally Posted By bpm990d: Any medical detachment should be required to read about Cpt. Ben Salomon before they qualify. If they show a lack of tiddlywink spirit after that, then they should all be given remedial physical training until they all vomit. Originally Posted By bpm990d: Originally Posted By doubleclaw: I watched in tooth-grinding rage as a USAR MED DET of a hundred "soldiers" took four days (!) to finish on the 25m range at Fort Wolters. No amount of remedial training will work on people who simply don't give a fuck. Any medical detachment should be required to read about Cpt. Ben Salomon before they qualify. If they show a lack of tiddlywink spirit after that, then they should all be given remedial physical training until they all vomit. So much for keeping firearms out of the medical spaces. 
|
I sell firearms produced by the finest child labor in the world, be it Filipino, Muslim, Mormon, Arizonan, or Texan.
|
Originally Posted By rb889: It does make you wonder what we could be seeing if the M16 had been originally designed with a longer COAL in mind. Originally Posted By rb889: Originally Posted By PacificNic: Originally Posted By spydercomonkey: It seems like ICAR may actually be built not just for 6 ARC, but for High Pressure 6mm ARC. Like going from the current lame 52kpsi to 80-100kpsi.... Here the video mentions that he fired the ICAR launching 108gr @ 3100fps from a 18", which is cookoo bananas speed. Should begin 15:09 https://www.youtube.com/watch?si=XLC56qVVClSrSNbr&t=909&v=lF47B1otpvM&feature=youtu.be This high pressure pedigree is also why I think the new HICAR will be a 5.56 version of the ICAR. The big limitation is that the URG has to be compatible with existing M4/M16 receivers. ICAR uses a different magwell length, etc. The thing to remember is that - in the words of the SOF Lethality PM - this is basically a science project. They are trying to see if 5.56mm high pressure is even really feasible with that restriction before they commit to funding development of a whole new system. ICAR is fantastic because they were allowed to break the mold that everyone else was trying to fit. Until the uppers are submitted and tested, we won't have scientific validation that the concept works or doesn't. We then have to hope and pray that they make the right decision on how to move forward with those results. It does make you wonder what we could be seeing if the M16 had been originally designed with a longer COAL in mind. Definitely a top priority change for any gun loving time traveler. Would have massively upgraded the long range performance potential of 5.56. The Steyr AUG allows a longer COL (theres a good bit of space in the mag, at least a pasta width between bullet tip and magwall). But afaik no one has ever taken advantage of this. But it does show the potential for something like a Six8 in 5.56 being able to "dual fuel" with regular 5.56 as well as "5.56 long". 
|
|
Originally Posted By spydercomonkey: Definitely a top priority change for any gun loving time traveler. Would have massively upgraded the long range performance potential of 5.56. The Steyr AUG allows a longer COL (theres a good bit of space in the mag, at least a pasta width between bullet tip and magwall). But afaik no one has ever taken advantage of this. But it does show the potential for something like a Six8 in 5.56 being able to "dual fuel" with regular 5.56 as well as "5.56 long". https://i.ibb.co/F4xdwK99/AUG-COL-vs-PMAG-copy.jpg Originally Posted By spydercomonkey: Originally Posted By rb889: Originally Posted By PacificNic: Originally Posted By spydercomonkey: It seems like ICAR may actually be built not just for 6 ARC, but for High Pressure 6mm ARC. Like going from the current lame 52kpsi to 80-100kpsi.... Here the video mentions that he fired the ICAR launching 108gr @ 3100fps from a 18", which is cookoo bananas speed. Should begin 15:09 https://www.youtube.com/watch?si=XLC56qVVClSrSNbr&t=909&v=lF47B1otpvM&feature=youtu.be This high pressure pedigree is also why I think the new HICAR will be a 5.56 version of the ICAR. The big limitation is that the URG has to be compatible with existing M4/M16 receivers. ICAR uses a different magwell length, etc. The thing to remember is that - in the words of the SOF Lethality PM - this is basically a science project. They are trying to see if 5.56mm high pressure is even really feasible with that restriction before they commit to funding development of a whole new system. ICAR is fantastic because they were allowed to break the mold that everyone else was trying to fit. Until the uppers are submitted and tested, we won't have scientific validation that the concept works or doesn't. We then have to hope and pray that they make the right decision on how to move forward with those results. It does make you wonder what we could be seeing if the M16 had been originally designed with a longer COAL in mind. Definitely a top priority change for any gun loving time traveler. Would have massively upgraded the long range performance potential of 5.56. The Steyr AUG allows a longer COL (theres a good bit of space in the mag, at least a pasta width between bullet tip and magwall). But afaik no one has ever taken advantage of this. But it does show the potential for something like a Six8 in 5.56 being able to "dual fuel" with regular 5.56 as well as "5.56 long". https://i.ibb.co/F4xdwK99/AUG-COL-vs-PMAG-copy.jpg Six8 just gives a wider mag box for more efficient double stack, it doesn't add COL, IIRC. |
I sell firearms produced by the finest child labor in the world, be it Filipino, Muslim, Mormon, Arizonan, or Texan.
|
Originally Posted By spydercomonkey: Not a great projectile, but these Shell Shock commercialy available loads are hitting 2900fps+ from a 10.5" https://badlandsmunitionsco.com/product/5-56-s-s-55gr-193-ammo/ https://badlandsmunitionsco.com/wp-content/uploads/2023/12/55gr-v-max-scaled.webp NAS3 cases became my go-to for 300blk. Bigger bore probably helps. Badlands, Phantom Defense and BlackArc are putting it out. Funny thing is that PSA dipped their toes into it awhile ago, but it never took off. Still on their website and I see there are actually fairly recent comments, so maybe they are getting back into it? https://palmettostatearmory.com/aac-5-56-nato-55-grain-fmj-shell-shock-ammo-250rd-with-aac-blue-30-cal-ammo-can.html |
|
Originally Posted By rb889: It does make you wonder what we could be seeing if the M16 had been originally designed with a longer COAL in mind. Or even a "fatter" cartridge case... aka.. the 224 Valkyrie / 22 Nosler. |
*Hold on to your AR-15s. Their magic must be very powerful, or they wouldn’t want them.*
JAFOM.... Just another fat old man.
________________________________
TOGC,IADC
JAFOM.... Just another fat old man.
________________________________
TOGC,IADC
|
Originally Posted By BrandonP: PSA wasn't loading it hot enough to see the benefits. I see. I think that is/was the case with some NovX ammo as well. Hopefully PSA loads them warmer when they back into things. I noticed another company has jumped into the mix. Never heard of Delta Co Munitions. https://deltacomunitions.com/ammunition/300-blackout/300-blackout-apex-overwatch/300-blackout-110gr-controlled-chaos-tipped-nas3/ I do think NAS3 (and better bolt/barrel material) is the easy way forward. We shall see if someone comes up with some dies to be able to reload non-straightwall shells. |
|
Originally Posted By backbencher: Six8 just gives a wider mag box for more efficient double stack, it doesn't add COL, IIRC. Originally Posted By backbencher: Originally Posted By spydercomonkey: Originally Posted By rb889: Originally Posted By PacificNic: Originally Posted By spydercomonkey: It seems like ICAR may actually be built not just for 6 ARC, but for High Pressure 6mm ARC. Like going from the current lame 52kpsi to 80-100kpsi.... Here the video mentions that he fired the ICAR launching 108gr @ 3100fps from a 18", which is cookoo bananas speed. Should begin 15:09 https://www.youtube.com/watch?si=XLC56qVVClSrSNbr&t=909&v=lF47B1otpvM&feature=youtu.be This high pressure pedigree is also why I think the new HICAR will be a 5.56 version of the ICAR. The big limitation is that the URG has to be compatible with existing M4/M16 receivers. ICAR uses a different magwell length, etc. The thing to remember is that - in the words of the SOF Lethality PM - this is basically a science project. They are trying to see if 5.56mm high pressure is even really feasible with that restriction before they commit to funding development of a whole new system. ICAR is fantastic because they were allowed to break the mold that everyone else was trying to fit. Until the uppers are submitted and tested, we won't have scientific validation that the concept works or doesn't. We then have to hope and pray that they make the right decision on how to move forward with those results. It does make you wonder what we could be seeing if the M16 had been originally designed with a longer COAL in mind. Definitely a top priority change for any gun loving time traveler. Would have massively upgraded the long range performance potential of 5.56. The Steyr AUG allows a longer COL (theres a good bit of space in the mag, at least a pasta width between bullet tip and magwall). But afaik no one has ever taken advantage of this. But it does show the potential for something like a Six8 in 5.56 being able to "dual fuel" with regular 5.56 as well as "5.56 long". https://i.ibb.co/F4xdwK99/AUG-COL-vs-PMAG-copy.jpg Six8 just gives a wider mag box for more efficient double stack, it doesn't add COL, IIRC. It is wider and slightly longer due to more polymer in front/spine to accommodate the larger pmag. Theoretically would be possible to put a steel mag in it too with thinner walls for even more OAL gain, should a company ever decide to dabble in it. |
|
Something I totally don't get... 5.56 has been loaded with a whole range of various projectiles. Pick a weight. US M855 doesn't fragment well out of short barrels at longer ranges, abd performance sucks. Swiss equivalent, which SHOULD be virtually equal, isn't: it truly almost never fragments. On the other hand, 5.56 from other sources varies greatly: some fragments reliably. The point? Terminal effectiveness of the 5.56 varies with bullet construction. Arguably, we could instantly increase the performance of the 5.56 by modifying bullet construction. Period. End of discussion. But no. Our military can never take the easy, effective route. Their answer is " let's firewall the pressure, and drive it faster!". The problem? You just KNOW they aren't going to really dial in everything else .. excessive port pressures. Shortened barrel life. Component wear and tear. And while barrel life might be 4000 or 6000 or 8000, Army is NEVER going to reliably and consistently issue new rifles ( or new barrels) at that point. There are going to be 11B's carrying weapon systems into the field with worn out barrels and inconsistent reliability .. It's not new: the Swiss played with Tombac jacketed bullets decades ago. They abandoned it because of excessive barrel wear. "But but but we need to blow thru 1/2" plate steel at a gazillion yards!". There's something stupid. It's FN, pushing for adoption of their Minimi in the 1970''s and designing the whole ' it'll punch a Soviet issue helmet at 600 yards " thing, which gave us the SS109 bullet in the original M855 load, and all of its problems with ineffectiveness. This is going to be an utter shitshow. |
|
Originally Posted By panthermark: Outside of 5.56 projectile/mag compatibility, why not 6MAX in an NAS3 case so that at least the bolt is compatible? Straight metal 350 Legend mags seem to work. Read the posted interview. "The advantage for SOF operators is I’ve got, say, the Green Berets who do a lot of partnering with foreign SOF operators, but there’s no [6.8mm] ammo running around central Africa, or you know, pick your favorite spot where we like to do partnering operations around the world. But there’s a lot of 5.56mm and other common cartridges of that nature, and so what we want to…achieve is maybe not the same effect as what the Army’s done with the M7 and the M8 and that high-velocity ammunition that they have, but where could we get close to that in 5.56 and potentially other calibers in the future." |
|
Originally Posted By panthermark: It is all basically better new fangled space age materials. But yeah, when something goes tits up, it could get ugly. Originally Posted By panthermark: Originally Posted By CheemsK1500: I have a feeling a lot of bolt lugs are about to be sacrificed. It is all basically better new fangled space age materials. But yeah, when something goes tits up, it could get ugly. Shouldn't be any more of an issue with a properly gassed gun. Originally Posted By medieval_flail: The reason for short barrels is reducing weight and size. Small arms aren't going to dominate a near peer conflict. Until we can effectively mitigate the drone threat, the US will not engage in another ground war making small arms development for big Army relatively moot in future planning. |
|
Originally Posted By FrankW134: Shouldn't be any more of an issue with a properly gassed gun. It will be interesting to see how it is properly gassed to reliably run at ranges of 58KPSI to 82KPSI out of a barrel no longer than 12 inches. That is 300blk super/sub kpsi differences, only with more pressure. That actually gives me an idea/question for GD. |
Joined:
Apr 2023
Posts:
328
EE: 100% (4)
FL, USA
|
Originally Posted By Heartbreak3r: Could we see a shift to smoothbore barrels with non-rotationally stabilized projectiles to solve the extreme barrel wear of high pressure and boost velocity? Originally Posted By Heartbreak3r: Could we see a shift to smoothbore barrels with non-rotationally stabilized projectiles to solve the extreme barrel wear of high pressure and boost velocity? APFSDS as well as spinning sabot rounds exist but require the round to be smaller than the bore it's going through. Probably a lot harder to manufacture and I don't know how accurate they are out of small arms. Originally Posted By FrankW134: Until we can effectively mitigate the drone threat, the US will not engage in another ground war making small arms development for big Army relatively moot in future planning. The drone threat isn't going away, especially with fiber optic drones. |
|
Originally Posted By medieval_flail: The drone threat isn't going away, especially with fiber optic drones. I am not as convinced, though maybe this will hold. It seems to me like drones really became relevant in Ukraine once both sides ran out of artillery. They were dropping so much ordnance on each other so constantly that they blew through the supplies that people were willing to commit. Drones will have continued importance at the "tip of the spear" but I don't think they will continue to be the primary vehicle/method for payload delivery into the future. Maybe that isn't what you mean. It seems to be what a lot of people think. |
Joined:
Aug 2023
Posts:
9753
EE: 0% (0)
NC, USA
|
Originally Posted By bfoosh06: Or even a "fatter" cartridge case... aka.. the 224 Valkyrie / 22 Nosler. Logistics are far better on a skinnier cartridge . A .204 ruger based cartridge gives case capacity at or near grendel/ARC/SPC. You get more bolt material . Taking the COAL out to 2.8" with an SFAR pattern lower keeps everything else AR15 sized . Id recommend a 257 kimber at 80ksi. Itd be closer to creedmoor than grendel , but more compact and logistically advantageous than both . |
|
Originally Posted By frozenny: Something I totally don't get... 5.56 has been loaded with a whole range of various projectiles. Pick a weight. US M855 doesn't fragment well out of short barrels at longer ranges, abd performance sucks. Swiss equivalent, which SHOULD be virtually equal, isn't: it truly almost never fragments. On the other hand, 5.56 from other sources varies greatly: some fragments reliably. The point? Terminal effectiveness of the 5.56 varies with bullet construction. Arguably, we could instantly increase the performance of the 5.56 by modifying bullet construction. Period. End of discussion. But no. Our military can never take the easy, effective route. The US Military actually did this route, to tremendous success, with the M855A1 projectile - the biggest upgrade to the AR since the adoption of optics. Frag velocity M855 ~2700fps, vs ~1700fps for M855A1, dramatically improving effective range and making any barrel length effective out to 300+ yd. Can also punch through some types of Level III armor as well sheet steel and cinder blocks at close range. 
|
|
Originally Posted By PacificNic: I am not as convinced, though maybe this will hold. It seems to me like drones really became relevant in Ukraine once both sides ran out of artillery. They were dropping so much ordnance on each other so constantly that they blew through the supplies that people were willing to commit. Drones will have continued importance at the "tip of the spear" but I don't think they will continue to be the primary vehicle/method for payload delivery into the future. Maybe that isn't what you mean. It seems to be what a lot of people think. Unless drones are mitigated either through raw materials or chip shortages, or counter-UAS solutions, they will continue to be more efficient at destroying targets than artillery. You can buy 5-10 weaponized FPV drones for the cost of a single 155 shell. The cost per kg explosive delivered is substantially lower. |
|
Originally Posted By panthermark: It will be interesting to see how it is properly gassed to reliably run at ranges of 58KPSI to 82KPSI out of a barrel no longer than 12 inches. That is 300blk super/sub kpsi differences, only with more pressure. That actually gives me an idea/question for GD. Originally Posted By panthermark: Originally Posted By FrankW134: Shouldn't be any more of an issue with a properly gassed gun. It will be interesting to see how it is properly gassed to reliably run at ranges of 58KPSI to 82KPSI out of a barrel no longer than 12 inches. That is 300blk super/sub kpsi differences, only with more pressure. That actually gives me an idea/question for GD. The SIG Spear 6.8's on youtube have been shown working with regular brass case (~60kpsi) and hybrid high pressure (82kpsi) ammo, I believe by just switching the gas setting. So in theory something like that for 5.56 should also be doable. However we've yet to see what we'd call a 'military grade' adjustable gas system for DI, so perhaps HICAR will end up an adjustable gas Piston? |
|
Originally Posted By BrandonP: Unless drones are mitigated either through raw materials or chip shortages, or counter-UAS solutions, they will continue to be more efficient at destroying targets than artillery. You can buy 5-10 weaponized FPV drones for the cost of a single 155 shell. The cost per kg explosive delivered is substantially lower. Maybe, but I think supply chain and production are the bigger issues there. Electronics vs. pure mechanics. I'm not saying drones go away forever, and maybe they do replace artillery. I don't think that's the case, but only time will tell. |
|
Shell Shock being picked up by CBC (parent of Magtech and several others.) Could be in prep for mass production of higher performance 5.56 and other calibers. https://forum.cartridgecollectors.org/t/shell-shock-technologies-enters-into-collaboration-with-cbc-global-ammunition-for-production-of-nas3-hybrid-case-stainless-steel-cartridges-and-global-marketing/71045 This collaboration is focused on the industrialization and global commercialization of SST’s proprietary NAS3™ hybrid case technology across multiple military and commercial calibers including: • 5.56x45 • 7.62x51 • .277 Fury (6.8mm) • .338 Lapua • .50 BMG • 9mm CBC brings world-class manufacturing capabilities, global reach, and deep military and commercial market relationships. Together, we believe this collaboration positions SST technology for large-scale adoption across future military systems and commercial applications worldwide. 
|
|
Page 117-120 Ammo info from SIG... please note the barrel lengths tested from. 5.56, 6.5CM. 7.62x51 HYBRID, 6.8 Hybrid https://www.google.com/url?sa=t&source=web&rct=j&opi=89978449&url=https://plusultratr.com/wp-content/uploads/catalogos/2026%2520DIGITAL_SPREAD_version.pdf&ved=2ahUKEwiUk7SUhueUAxVLGTQIHcN-Go04FBAWegQINhAB&usg=AOvVaw0VaPVdkaJCzQk0QdL6fOju |
*Hold on to your AR-15s. Their magic must be very powerful, or they wouldn’t want them.*
JAFOM.... Just another fat old man.
________________________________
TOGC,IADC
JAFOM.... Just another fat old man.
________________________________
TOGC,IADC
|
Originally Posted By bfoosh06: Page 117-120 Ammo info from SIG... please note the barrel lengths tested from. 5.56, 6.5CM. 7.62x51 HYBRID, 6.8 Hybrid https://www.google.com/url?sa=t&source=web&rct=j&opi=89978449&url=https://plusultratr.com/wp-content/uploads/catalogos/2026%2520DIGITAL_SPREAD_version.pdf&ved=2ahUKEwiUk7SUhueUAxVLGTQIHcN-Go04FBAWegQINhAB&usg=AOvVaw0VaPVdkaJCzQk0QdL6fOju Excellent find   The 97gr Tungsten offering is fascinating - zooming in we see it's a "Tandem Warhead" design, with a front penetrator designed to shatter the ceramic, with a pointed 2nd penetrator designed to then punch through that ceramic fracture. 
|
Even the 7.62x51 Hybrid caught my attention.... granted this is from a 24" barrel, but...971 meters per second (m/s) is equal to 3185.70 feet per second.
|
*Hold on to your AR-15s. Their magic must be very powerful, or they wouldn’t want them.*
JAFOM.... Just another fat old man.
________________________________
TOGC,IADC
JAFOM.... Just another fat old man.
________________________________
TOGC,IADC
|
Originally Posted By bfoosh06: Even the 7.62x51 Hybrid caught my attention.... granted this is from a 24" barrel, but...971 meters per second (m/s) is equal to 3185.70 feet per second. https://www.ar15.com/media/mediaFiles/171545/Screenshot_2026-06-02_at_01-07-25_2026_D-3772113.png That's hauling ass. The 5.56 velocity seems impossible to me, at least for the barrel length they list - 62gr @ 3313fps from a 10.5". That's like +600fps more then regular 5.56 from the same barrel length, which doesn't seem in line with a +20kpsi boost. The 97gr @ 2500fps from a 10.5" seems more probable though, although I have no real baseline. |
|
Originally Posted By bfoosh06: I wonder if / how the New Proof Research PXT barrel tech factors into all this. Yeah it'll be interesting to see how they sell it. Apparently the price point is a little under $1k. SOCOM will have to weight 3 barrels from X MFG vs one Proof PXT assuming that price structure holds. |
|
Originally Posted By bfoosh06: I wonder if / how the New Proof Research PXT barrel tech factors into all this. I definitely think PXT and better barrel steels / coatings will be an enabler. Apparently the 80kpsi 7mm Backcountry was a major focus of their testing. And the basic progressive twist 1:500-1:7 style used by Proof has been used for decades by Germany in their 20-27mm Autocannons, so I suspect that style of twist progression would not really be patentable / we could see other barrel manufacturers use similar twists for their high pressure barrels. G$ is working on new barrel alloys, also for High Pressure: https://www.thefirearmblog.com/blog/army-geissele-carpenter-partner-on-next-gen-barrels-44826928 ChatGPT really crushed it with info on potential new coatings beyond regular chrome and nitride. There are apparently much more advanced nitridings that work in Aerospace but have not been used in firearms, and GPT also suggests that GNB 200 steel may be partially designed to work better with nitriding than regular 4150 steel. Whole GPT is worth perusing: https://chatgpt.com/share/6a20d3eb-24f8-83e8-9edd-50895c534c6f |
HICAR - High Pressure 82kpsi M855A1+ rifle for SOCOM (Page 3 of 5)
AR Sponsor
Join the Community
Your next conversation starts here.
Create your free account to join discussions, share your experience, save topics, and connect with the AR15.COM community.
- Join discussions
- Follow topics and replies
- Connect with fellow enthusiasts
Already a member? Sign in
Stay informed by subscribing to our Newsletter