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Posted: 6/29/2023 12:21:56 AM EDT
[#1]
KAK has a new dual ejector AR bolt. Y'all ought to try that in your radial delayed blowback guns.
 Attached FileKAK |
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MN, USA
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Posted: 6/29/2023 12:24:46 AM EDT
[#2]
Quote HistoryOriginally Posted By eodinert: KAK has a new dual ejector AR bolt. Y'all ought to try that in your radial delayed blowback guns. https://www.ar15.com/media/mediaFiles/6794/k_spek_kak_jpg-2867326.JPG KAK Do they cut the chamfers on the rear of the bolt lugs, or should we handle that ourselves? |
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USA
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Posted: 6/29/2023 12:48:15 AM EDT
[#3]
So has anyone put the buffer in a cmmg rdb upper yet?
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Posted: 6/29/2023 2:02:22 AM EDT
[#4]
Quote HistoryOriginally Posted By TheGunslinger: So has anyone put the buffer in a cmmg rdb upper yet? I will eventually. I do not have any hopes of it functioning. I also intend to try it with the Scheel buffer. |
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FL, USA
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Posted: 6/29/2023 6:26:59 AM EDT
[#5]
Quote HistoryOriginally Posted By backbencher: Thought the new CMMG radial delay guns had a fixed ejector? Discussed already below https://uzitalk.com/forums/index.php?threads/i-did-it-fixed-ejector-rdb.97420/ |
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FL, USA
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Posted: 6/29/2023 6:29:15 AM EDT
[#6]
Quote HistoryOriginally Posted By hdcharlie: Site still says it is in the bolt. If it was fixed it would most likely be in the lower, but since they sell just the upper... Quote HistoryOriginally Posted By hdcharlie: Originally Posted By backbencher:Thought the new CMMG radial delay guns had a fixed ejector? Site still says it is in the bolt. If it was fixed it would most likely be in the lower, but since they sell just the upper... Here is a picture I took from a Youtube vid and put on my website:   |
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FL, USA
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Posted: 6/29/2023 6:38:16 AM EDT
[Last Edit: amphibian]
[#7]
Quote HistoryOriginally Posted By texaspaulhouston: The new CMMG Dissent has the receiver mounted ejector and compact action but with RDB But I will mention it again, I personally am not interested in the Dissent 9mm RDB because: 1. Not full auto capable which I know most people don't care about 2. Most likely cannot be tuned 3. I don't care for side chargers On note 2, Many people including myself have stated that we were NOT impressed with the out of the box recoil impulse of the CMMG RDB in 9mm. However, since the original could be tuned it is a lot better IMHO, with the Tubb Flat spring and hydraulic buffer (my preferred is the RB5007) which BTW, @Droppoint later came to a similar conclusion with his testing to arrive at similar selection of components for straight blowback. In addition to the flat spring and hydraulic buffer, I currently run a .40SW bolt to run in 9mm to further the delay with a custom 9mm barrel that is headspaced for the .40SW bolt with the headspace slop removed. factory CMMG 9mm RDB with CMMG recommended buffer and spring  8" 9mm CMMG RDB factory config Now my tuned setup  8" 9mm CMMG RDB, mod'd 5.45 bolt, suppressed, fixed ejector RB5007 Again both videos are running semi auto and it is clear to see my tuned setup is way smoother. The fact you can't tune the Dissent makes it a deal breaker for me. Tubb flat spring + Kynshot 5007 + straight blowback 9mm is smoother than CMMG RDB with stock buffer and stock spring and no ejector spring issues to worry about However Tubb flat spring + Kynshot 5007 in a CMMG RDB is smoother than Tubb flat spring + Kynshot 5007 + straight blowback but then you have ejector spring failures at the 1K mark. |
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Posted: 6/29/2023 7:37:50 AM EDT
[#8]
Quote HistoryOriginally Posted By 45-Seventy: The only time you really need to operate the charging handle on the clock is table starts and my times are unchanged. It’s more of a “Huh, this is harder than it was before” thing than it is anything which affects performance. Quote HistoryOriginally Posted By 45-Seventy: Originally Posted By towerofpower94: Thanks. Ever had an issue manipulating it on the clock? Is the gain of reduced recoil worth the risk of a more difficult to operate system? I'm guessing the juice is worth the squeeze, as I think you're still using it, but wanted to confirm before I jump into the Scheels or a Maxim. The only time you really need to operate the charging handle on the clock is table starts and my times are unchanged. It’s more of a “Huh, this is harder than it was before” thing than it is anything which affects performance. Righto, thanks |
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MI, USA
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Posted: 6/29/2023 10:46:59 AM EDT
[#9]
Quote HistoryOriginally Posted By amphibian: Sounds like you are describing the upcoming Armanov buffer: https://www.armanov.com/buffer Not released yet but I did see Ian McCollum from Forgotten Weapons last weekend and he told me he has one in his hands for testing. Quote HistoryOriginally Posted By amphibian: Originally Posted By backbencher: Originally Posted By RDTCU: Originally Posted By backbencher: Do we have a working diagram of this thing? Are the ball bearings starting in the guide rod recess, and being forced out under recoil of the forward mass, thus accelerating the rearward mass? The answer is yes, but I'm not sure where the spring is acting in the Maxim design to force lockup. I drew this up a little over a year ago for use with a standard flatwire spring... https://www.ar15.com/media/mediaFiles/173511/PXL_20230627_192001916_jpg-2865631.JPG And finally started on the prototype a couple months ago. Being a dad makes some things slow going... https://www.ar15.com/media/mediaFiles/173511/PXL_20230226_025900383_jpg-2865647.JPG Ended up with a hydraulic buffer with custom weights and it's very slick, but still interested in the RDB. https://www.ar15.com/media/mediaFiles/173511/PXL_20230520_205950259_jpg-2865646.JPG Can you make a balanced recoil system? Bolt pushes back a toothed rod, annular weight in back of buffer tube moves forward b/c of gear at front of weight running on toothed rod, compressing normal recoil spring btwn weight & bolt? Not released yet but I did see Ian McCollum from Forgotten Weapons last weekend and he told me he has one in his hands for testing. What is being referred to as "balanced recoil' is not really a new concept. IIRC, mostly used for artillery. As with almost everything, one gets what one pays for. MHO, YMMV, etc. Be well. |
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Posted: 6/29/2023 10:53:00 AM EDT
[#10]
Quote HistoryOriginally Posted By s4s4u: Do they cut the chamfers on the rear of the bolt lugs, or should we handle that ourselves? Quote HistoryOriginally Posted By s4s4u: Originally Posted By eodinert: KAK has a new dual ejector AR bolt. Y'all ought to try that in your radial delayed blowback guns. https://www.ar15.com/media/mediaFiles/6794/k_spek_kak_jpg-2867326.JPG KAK Do they cut the chamfers on the rear of the bolt lugs, or should we handle that ourselves? You'd have to follow in amphibian's footsteps to cut the lugs at your desired angle (he did a 5.45x39mm bolt), you'd also have to enlarge the bolt face a titch to fit, since that's not a 5.45x39mm bolt. |
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MN, USA
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Posted: 6/29/2023 12:10:44 PM EDT
[#11]
Quote HistoryOriginally Posted By backbencher: You'd have to follow in amphibian's footsteps to cut the lugs at your desired angle (he did a 5.45x39mm bolt), you'd also have to enlarge the bolt face a titch to fit, since that's not a 5.45x39mm bolt. I guess that I was just pointing out that the bolt would not just drop in to an RDB upper. I have no desire nor the equipment to modify it so that it would and I expect 98% of members are in the same boat 
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Posted: 6/29/2023 12:42:49 PM EDT
[#12]
Quote HistoryOriginally Posted By hdcharlie: I took a lower with the RDS system and another lower with the "Gentle Recoil" system, along with a single 16" barreled upper, to the range this morning. I was shooting WCC 124gr +P ball ammo in both lowers. There were three shooters testing the carbine and we all came to the same conclusion. We agreed that the GR system was the equal or slightly better that the Maxim RDS. That conclusion was drawn using only one ammo type, so results might be different with other brands and bullet weights, pressures, etc. If the RDS has one major selling point, it's in its simplicity, with the caveat discussed below. Thanks for posting this - pretty much my conclusions as well. Good to know I wasn't biased in my conclusion that they were pretty similar. |
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Posted: 6/29/2023 2:21:11 PM EDT
[#13]
@Droppoint
What did you think about this part of my earlier post? One thing I'm finding curious and distressing is that carbine buffer tubes of different brands do not all have the same internal depth. Some are longer and some are shorter. This makes it difficult to get the RDS to just meet the bolt when the receiver halves are mated. Of course, I am assuming that that is the way the system should operate. I can see how a space between the bolt and the RDS could be problematic, or not, but I don't know. Having the RDS slightly compressed after installation should also not be desirable, but who knows. Maxim should have provided some guidance for the installation of the unit, but they didn't. |
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Posted: 6/29/2023 4:11:28 PM EDT
[#14]
Quote HistoryOriginally Posted By hdcharlie: @Droppoint What did you think about this part of my earlier post? One thing I'm finding curious and distressing is that carbine buffer tubes of different brands do not all have the same internal depth. Some are longer and some are shorter. This makes it difficult to get the RDS to just meet the bolt when the receiver halves are mated. Of course, I am assuming that that is the way the system should operate. I can see how a space between the bolt and the RDS could be problematic, or not, but I don't know. Having the RDS slightly compressed after installation should also not be desirable, but who knows. Maxim should have provided some guidance for the installation of the unit, but they didn't. I've found it very difficult to install with the buffer retainer in place, so I've removed the retainer on both guns that I am going to run the RDB in (I ordered a second one yesterday) which allows me to just drop the buffer into the tube before screwing the tube into the receiver. I had to have it unscrewed one turn from what it was when I was using a standard buffer in order to not pre-load the mechanism, in all 3 of the lowers that I have had it installed in. |
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Posted: 6/29/2023 5:03:45 PM EDT
[#15]
Quote HistoryOriginally Posted By chevrofreak:I've found it very difficult to install with the buffer retainer in place, so I've removed the retainer on both guns that I am going to run the RDB in (I ordered a second one yesterday) which allows me to just drop the buffer into the tube before screwing the tube into the receiver. I had to have it unscrewed one turn from what it was when I was using a standard buffer in order to not pre-load the mechanism, in all 3 of the lowers that I have had it installed in. I tried that, too, but just ended up with free-play between the bolt and the RDB. Somehow, I don't think that is a good idea. Some guidance from Maxim might be helpful. I did find one carbine buffer tube that works perfectly, but I have no idea where it came from or which manufacturer made it. Since I don't intend to buy another RDB, I suppose it doesn't matter. |
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FL, USA
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Posted: 6/29/2023 5:10:43 PM EDT
[#16]
Quote HistoryOriginally Posted By hdcharlie: I tried that, too, but just ended up with free-play between the bolt and the RDB. Somehow, I don't think that is a good idea. Some guidance from Maxim might be helpful. I did find one carbine buffer tube that works perfectly, but I have no idea where it came from or which manufacturer made it. Since I don't intend to buy another RDB, I suppose it doesn't matter. Quote HistoryOriginally Posted By hdcharlie: Originally Posted By chevrofreak:I've found it very difficult to install with the buffer retainer in place, so I've removed the retainer on both guns that I am going to run the RDB in (I ordered a second one yesterday) which allows me to just drop the buffer into the tube before screwing the tube into the receiver. I had to have it unscrewed one turn from what it was when I was using a standard buffer in order to not pre-load the mechanism, in all 3 of the lowers that I have had it installed in. I tried that, too, but just ended up with free-play between the bolt and the RDB. Somehow, I don't think that is a good idea. Some guidance from Maxim might be helpful. I did find one carbine buffer tube that works perfectly, but I have no idea where it came from or which manufacturer made it. Since I don't intend to buy another RDB, I suppose it doesn't matter. |
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Posted: 6/29/2023 5:22:58 PM EDT
[#17]
Quote HistoryOriginally Posted By amphibian: On a somewhat related note, I have a belt fed Ares (now Fightlite) upper receiver and the manual states you may or may not need a supplied spacer/washer to put in your buffer tube due to the varying dimensions of all the different buffer tubes out there. I just keep some quarters in my range box for various scenarios like this. I was on the McMaste-Carr site the other day looking for a set of variable thickness shims. They have them, and I would order a set or two if I was going to use the RDB in more than one lower. Instead, I'll just use my various uppers on the lower that works. As long as the bolt ends up in the same place in all the uppers, this should work. Damn, another measurement to worry about. I've never had this problem with a regular buffer/spring setup, except for the fact that I've had to remove some of the front face of the buffer tube occasionally when the tube had to be screwed in too far in order to hold the buffer retainer in place. |
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Posted: 6/29/2023 5:34:49 PM EDT
[#18]
Is there no way to adjust the length of the central arbor in the poly buffer base? I suppose quarters will work.
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Posted: 6/29/2023 10:55:52 PM EDT
[Last Edit: chevrofreak]
[#19]
Quote HistoryOriginally Posted By chevrofreak: I decided to burn even more money and bought a TACCOM Super Feed 16 ULW-B (mid brake) barrel, a Joe Bob Spartan side charging upper, a TACCOM bolt and a 6oz full carbon fiber handguard to build a new competition upper to test with this buffer. Parts should be here this week, and I have a match coming on Sunday so I will give my thoughts after that. Between yesterday and today all of these new parts showed up. It resulted in a very light build.  I quickly cut the carbon fiber handguard for the compensator.  Then I ran to the range with just enough light left to give it a try. https://youtube.com/shorts/JCBO4pukm1s The very lightweight setup has minimal recoil, minimal dot movement and is very fast to shoot. I guess we will see how it does at the steel match this weekend. |
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MN, USA
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Posted: 6/29/2023 11:57:02 PM EDT
[#20]
So when y'all say it's hard to charge, how hard? If one were to smack the butt against his leg while he pulled the CH, would that suffice? More, or less, effort required?
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Posted: 6/30/2023 12:09:15 AM EDT
[#21]
Quote HistoryOriginally Posted By s4s4u: So when y'all say it's hard to charge, how hard? If one were to smack the butt against his leg while he pulled the CH, would that suffice? More, or less, effort required? Think of it like pulling on a 2" long torque wrench that doesn't move until you hit its torque setting and instead of clicking as you hit 12lbs of force it just instantly breaks loose and only takes a couple of pounds from there on back. When I had my girlfriend try it out I had to show her what mortaring was. When she did that on the concrete bench she was able to charge the rifle. I don't think I would rely on that. |
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OH, USA
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Posted: 6/30/2023 6:22:33 AM EDT
[Last Edit: swOHmatt]
[#22]
Making to much about the charging effort? Not saying it is easy, but how often do you use the charging handle? Once to load the weapon. After that an empty mag activates the bolt hold open. A strategic reload doesn’t require the charging handle. An FTF or FTE will result in the bolt remaining out of battery, the roller delay released and it charges with the same effort as a blow back.
Other than the first loading of the chamber you never touch the charging handle. Looking forward to trying this when it arrives. |
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Posted: 6/30/2023 9:47:30 AM EDT
[#23]
How about reducing gas to face when suppressed? That’s what I’m most interested in. My AR9 bleeds my eyes with any can on it, I hate it.
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Posted: 6/30/2023 10:18:03 AM EDT
[#24]
Quote HistoryOriginally Posted By VeritatisUnus: How about reducing gas to face when suppressed? That’s what I’m most interested in. My AR9 bleeds my eyes with any can on it, I hate it. This and port pop would be my biggest interests in something like this. |
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TX, USA
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Posted: 6/30/2023 11:21:14 AM EDT
[#25]
if someone has the Taccom MDRS - how does this compare - The Taccom systems seems way more adjustable and less moving parts to ware out. I have a MDRS and it works great and you can fine tune it for your loads.
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Posted: 6/30/2023 11:26:04 AM EDT
[Last Edit: Blowback9]
[#26]
Quote HistoryOriginally Posted By swOHmatt: Making to much about the charging effort? Not saying it is easy, but how often do you use the charging handle? Once to load the weapon. After that an empty mag activates the bolt hold open. A strategic reload doesn’t require the charging handle. An FTF or FTE will result in the bolt remaining out of battery, the roller delay released and it charges with the same effort as a blow back. Other than the first loading of the chamber you never touch the charging handle. Looking forward to trying this when it arrives. I don't think he is making "too much" about the charging effort. Depending on your build, your weight, and your upper body strength, it can be difficult to impossible to charge an AR with the Maxim system in place. Some people, specifically beefy guys, will have no problem. I'm plenty strong for my size, but I have a "small/medium" build and weigh about the same as when I was in high school. I have to brace the stock against my chest to get enough leverage to pop the Maxim free. My wife can't make it budge, so she can't even charge it the first time. She can manipulate her 5.56mm AR-15 like a pro. Compared to the pinky-finger easy charging of a regular AR9 or AR-15, the Maxim is a very different experience and is not going to be suitable for many people. |
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Posted: 6/30/2023 11:28:26 AM EDT
[#27]
Quote HistoryOriginally Posted By hdcharlie: @Droppoint What did you think about this part of my earlier post? One thing I'm finding curious and distressing is that carbine buffer tubes of different brands do not all have the same internal depth. Some are longer and some are shorter. This makes it difficult to get the RDS to just meet the bolt when the receiver halves are mated. Of course, I am assuming that that is the way the system should operate. I can see how a space between the bolt and the RDS could be problematic, or not, but I don't know. Having the RDS slightly compressed after installation should also not be desirable, but who knows. Maxim should have provided some guidance for the installation of the unit, but they didn't. I had to unscrew one of the buffer tubes 1 turn to reduce the pre-load. Another tube was just fine. It would be great if Maxim included information about this, but I think they're doing what software people call "testing in production". We're the unpaid (even worse, we had to pay for it) beta-testers. |
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Posted: 6/30/2023 11:47:51 AM EDT
[Last Edit: hdcharlie]
[#28]
Quote HistoryOriginally Posted By Droppoint: I had to unscrew one of the buffer tubes 1 turn to reduce the pre-load. Another tube was just fine. It would be great if Maxim included information about this, but I think they're doing what software people call "testing in production". We're the unpaid (even worse, we had to pay for it) beta-testers. I noted that you said "reduce the preload", not eliminate it. My concern in that scenario is how much preload can the system accept and still function as intended. If the setup should be with the bolt just touching the RDB without compressing it at all, getting that right with the various buffer tube measurements would be problematic. I have inquired about this situation with Maxim, but, so far, my questions have been ignored. Maybe they did all their testing with a buffer tube that happened to fit correctly, and had no reason to take this into consideration. I hope someone in their organization is following this thread. |
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Posted: 6/30/2023 11:51:04 AM EDT
[#29]
Quote HistoryOriginally Posted By RDTCU: This and port pop would be my biggest interests in something like this. Quote HistoryOriginally Posted By RDTCU: Originally Posted By VeritatisUnus: How about reducing gas to face when suppressed? That’s what I’m most interested in. My AR9 bleeds my eyes with any can on it, I hate it. This and port pop would be my biggest interests in something like this. I have found it to be very effective at reducing port pop and gas to the face. |
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Posted: 6/30/2023 12:20:24 PM EDT
[#30]
Quote HistoryOriginally Posted By hdcharlie: I noted that you said "reduce the preload", not eliminate it. My concern in that scenario is how much preload can the system accept and still function as intended. If the setup should be with the bolt just touching the RDS without compressing it at all, getting that right with the various buffer tube measurements would be problematic. I have inquired about this situation with Maxim, but, so far, my questions have been ignored. Maybe they did all their testing with a buffer tube that happened to fit correctly, and had no reason to take this into consideration. I hope someone in their organization is following this thread. I reduced the preload to essentially zero. The buffer and bolt were touching snug, not compressing. |
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Posted: 6/30/2023 1:59:26 PM EDT
[#31]
Quote HistoryOriginally Posted By chevrofreak: Between yesterday and today all of these new parts showed up. It resulted in a very light build. https://www.ar15.com/media/mediaFiles/74212/IMG20230629194209-2868379.jpg I quickly cut the carbon fiber handguard for the compensator. https://www.ar15.com/media/mediaFiles/74212/IMG20230629194307-2868380.jpg Then I ran to the range with just enough light left to give it a try. https://youtube.com/shorts/JCBO4pukm1s The very lightweight setup has minimal recoil, minimal dot movement and is very fast to shoot. I guess we will see how it does at the steel match this weekend. That’s pretty close to how I set up my race guns. |
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Posted: 6/30/2023 5:39:31 PM EDT
[#32]
Quote HistoryOriginally Posted By 45-Seventy: That’s pretty close to how I set up my race guns. I normally run an 8" SBR in PCC division, but now that I am classified (A class thanks to a recent special classifier) I am getting more into it and wanted something that I could travel with. I had shot a friend's MPX when I broke a firing pin at a Steel Challenge match a few years ago and he had a barrel like this on his rifle and I really liked it. |
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Posted: 7/1/2023 2:31:34 PM EDT
[#33]
Maxim RDB update: The pre-load significantly affects charging force.
Video explanation:  Maxim drop-in Roller Delay "RDB": The preload makes a difference! I put the Maxim system back in one of my builds and set the buffer tube so the RDB was barely touching the bolt. The charging handle took about 32 lbs. of force to pull back (measured with a digital scale on the handle). I had the same struggle I had before - very difficult to pull, requiring bracing the back of the tube against my body to pop the system past the "wall" of the mechanical delay. I tightened the buffer tube 1 turn into the receiver. Now, closing the upper receiver caused the bolt to push the RDB back firmly into the tube. This pre-loaded the mechanical delay. The charging handle now took about 26-28 lbs. of pressure to pull back. This 9-10% change is enough of a difference to make a big difference. I could pull the charging handle back without bracing the rear of the tube. It's still more than normal, but now it's completely manageable. This is why I believe some people are finding it easier to pull the charging handle back with the Maxim system in place. All my range time was done with NO pre-load. Pre-loading the system, I would expect, will reduce the available resistance to the blowback forces from firing. Is this OK? We don't know and Maxim neglected to provide guidance on pre-loading the RDB captured system. I'll take it out and do some more testing with the buffer pre-loaded when I can. |
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Posted: 7/1/2023 5:45:42 PM EDT
[Last Edit: jt526]
[#34]
Got mine in and installed, stout is how I would describe the charging, doable, but dang. Had to change out the charging handle right away from stock to a BCM mod4 I had handty and will likely do something like the geiselle, or raptor SD maybe. Needs a lot of charging handle for sure. Range trip maybe tomorrow. More than likely going to go with the MEAN system still when released, but TBD.
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Posted: 7/1/2023 11:59:40 PM EDT
[#35]
Quote HistoryOriginally Posted By Droppoint: Maxim RDB update: The pre-load significantly affects charging force. Video explanation:  https://www.youtube.com/watch?v=3PLr4z1kDrUI put the Maxim system back in one of my builds and set the buffer tube so the RDB was barely touching the bolt. The charging handle took about 32 lbs. of force to pull back (measured with a digital scale on the handle). I had the same struggle I had before - very difficult to pull, requiring bracing the back of the tube against my body to pop the system past the "wall" of the mechanical delay. I tightened the buffer tube 1 turn into the receiver. Now, closing the upper receiver caused the bolt to push the RDB back firmly into the tube. This pre-loaded the mechanical delay. The charging handle now took about 26-28 lbs. of pressure to pull back. This 9-10% change is enough of a difference to make a big difference. I could pull the charging handle back without bracing the rear of the tube. It's still more than normal, but now it's completely manageable. This is why I believe some people are finding it easier to pull the charging handle back with the Maxim system in place. All my range time was done with NO pre-load. Pre-loading the system, I would expect, will reduce the available resistance to the blowback forces from firing. Is this OK? We don't know and Maxim neglected to provide guidance on pre-loading the RDB captured system. I'll take it out and do some more testing with the buffer pre-loaded when I can. This sort of testing & write up are what make you & amphibian so valuable to us. Thank you. |
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Posted: 7/2/2023 12:02:33 AM EDT
[#36]
Quote HistoryOriginally Posted By Droppoint: Maxim RDB update: The pre-load significantly affects charging force. Video explanation: https://www.youtube.com/watch?v=3PLr4z1kDrUI put the Maxim system back in one of my builds and set the buffer tube so the RDB was barely touching the bolt. The charging handle took about 32 lbs. of force to pull back (measured with a digital scale on the handle). I had the same struggle I had before - very difficult to pull, requiring bracing the back of the tube against my body to pop the system past the "wall" of the mechanical delay. I tightened the buffer tube 1 turn into the receiver. Now, closing the upper receiver caused the bolt to push the RDB back firmly into the tube. This pre-loaded the mechanical delay. The charging handle now took about 26-28 lbs. of pressure to pull back. This 9-10% change is enough of a difference to make a big difference. I could pull the charging handle back without bracing the rear of the tube. It's still more than normal, but now it's completely manageable. This is why I believe some people are finding it easier to pull the charging handle back with the Maxim system in place. All my range time was done with NO pre-load. Pre-loading the system, I would expect, will reduce the available resistance to the blowback forces from firing. Is this OK? We don't know and Maxim neglected to provide guidance on pre-loading the RDB captured system. I'll take it out and do some more testing with the buffer pre-loaded when I can. I played with preloading it earlier and I could definitely tell there was less force necessary to charge it, but at one point something locked up and no matter how much force I applied I could not get the bolt to cycle. It was rather odd, so I just put it back the way it was and had no further problems. |
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Posted: 7/2/2023 4:00:28 AM EDT
[#37]
Quote HistoryOriginally Posted By chevrofreak: I played with preloading it earlier and I could definitely tell there was less force necessary to charge it, but at one point something locked up and no matter how much force I applied I could not get the bolt to cycle. It was rather odd, so I just put it back the way it was and had no further problems. Curious. I'll watch for this happening. |
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PA, USA
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Posted: 7/2/2023 12:25:35 PM EDT
[Last Edit: Dan_GSR]
[#38]
Intrested to hear how the preload effects reoil impulse
You could also preload further by dropping a quarter in the back of the buffer tube But that might short stroke |
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Posted: 7/2/2023 1:02:43 PM EDT
[#39]
When you guys are talking about “preload”, are you putting the buffer in a state of partial unlock?
Because that seems like a recipe for unpleasantness. |
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Posted: 7/2/2023 2:07:59 PM EDT
[#40]
Quote HistoryOriginally Posted By 45-Seventy: When you guys are talking about “preload”, are you putting the buffer in a state of partial unlock? Because that seems like a recipe for unpleasantness. Seems like a partial unlock would negate the effect of the bearings and then you'd have only the spring doing any work. |
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Posted: 7/2/2023 5:52:02 PM EDT
[#41]
Quote HistoryOriginally Posted By hdcharlie: Seems like a partial unlock would negate the effect of the bearings and then you'd have only the spring doing any work. That's my assessment as well, but we don't know for sure if the system was designed for the bolt to push it slightly back in the tube (like the bolt does with a regular buffer) or not. Maxim provided zero guidance on their product site and provides no directions in the package. |
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Posted: 7/2/2023 11:24:07 PM EDT
[Last Edit: chevrofreak]
[#42]
The steel match went OK today; I didn't shoot as well as I had hoped, but I think it was due to shooting a gun that was so dissimilar to what I've been using for the last couple of years. The recoil impulse is so light on my new upper build that I pushed myself to run too fast and didn't get the hits that I should have. I still managed 5th overall out of 32 shooters.
After the match I had the opportunity to shoot two DaVinci Machining PCC's owned by the overall match winner. His guns are super nice quality, and one used the Scheel gen 1 buffer, and the other was the gen 2. Both of those guns had significantly sharper recoil and more dot bounce than mine did. After he shot my rifle he looked at me in disbelief of how soft it shot, and commented to that fact. Both of his rifles were also heavier than mine. I think that if you are someone with good upper body strength, it is a mistake to overlook this system because of its much higher required charging force, when it has plenty of benefits to make up for that detractor. |
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CT, USA
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Posted: 7/3/2023 6:51:33 AM EDT
[#43]
If enough of these units wind up in circulation, I wouldn't be surprised to see a charging handle appear on the market that has a handle that cams against the rear of the upper receiver to provide an initial opening effort that is assisted like the charging handles on HK rifles. If Maxim Defense is smart and is paying attention they are working on one right now.
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Posted: 7/3/2023 7:59:10 AM EDT
[Last Edit: Blowback9]
[#44]
Quote HistoryOriginally Posted By chevrofreak: I think that if you are someone with good upper body strength, it is a mistake to overlook this system because of its much higher required charging force, when it has plenty of benefits to make up for that detractor. Quote HistoryOriginally Posted By chevrofreak: I think that if you are someone with good upper body strength, it is a mistake to overlook this system because of its much higher required charging force, when it has plenty of benefits to make up for that detractor. I agree. It does provide quite the recoil reduction. Thanks for comparing against the Sheel - I've had a bunch of people ask about that. Originally Posted By Silverbear_51: If enough of these units wind up in circulation, I wouldn't be surprised to see a charging handle appear on the market that has a handle that cams against the rear of the upper receiver to provide an initial opening effort that is assisted like the charging handles on HK rifles. If Maxim Defense is smart and is paying attention they are working on one right now. Like this one? https://store.springfield-armory.com/levar-ratcheting-charging-handle/  I have one on order, but it'll probably be a month before it gets here. Got it for a great price, but the vendor has crappy delivery times. |
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CT, USA
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Posted: 7/3/2023 8:09:14 AM EDT
[#45]
Yeah, something like that, but not one that has to be deployed from the folded-up position to use and not so "swoopy" looking. It's a good start, though.
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FL, USA
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Posted: 7/3/2023 9:25:06 AM EDT
[#46]
Quote HistoryOriginally Posted By Silverbear_51: Yeah, something like that, but not one that has to be deployed from the folded-up position to use and not so "swoopy" looking. It's a good start, though. |
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CT, USA
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Posted: 7/3/2023 9:36:45 AM EDT
[#47]
So have you made it to the range yet? I'm waiting for the usual Amphibian excellent write-up.
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FL, USA
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Posted: 7/3/2023 10:06:51 AM EDT
[#48]
Quote HistoryOriginally Posted By Silverbear_51: So have you made it to the range yet? I'm waiting for the usual Amphibian excellent write-up. |
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CT, USA
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Posted: 7/3/2023 10:45:49 AM EDT
[#49]
Yer killing me, LOL! Have a great holiday with the family.
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HI, USA
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Posted: 7/3/2023 1:06:18 PM EDT
[#50]
Question for those who got their in, especially competition shooters
What kind of loads are you running, regular full power or light competition loads I ordered one about 5 minutes after I read about them on page one and I’m concerned my if my light PCC loads will run it |
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