A new caliber - 40 Extreme

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[ARCHIVED THREAD] - A new caliber - 40 Extreme

Posted: 10/17/2006 8:23:30 PM EDT

This cartridge was developed at the request of a customer. Essentially, it takes the concept of the 440 CorBon, but with two distinct differences. First, the case is necked down to 40 caliber to take advantage of .40/10mm bullets. Second, it uses the 7.62 x 39 rim, as opposed to the .514 rim of the .440 CorBon. The name was chosen as the combination of dimensions is about at the extreme edge of what the bolt will survive ...

Shown are two rounds with 180 JHP as well as a 458 SOCOM. The magazine requires installation of a spacer and a shortened follower

Anticipated performance out of a 16" barrel is 2175 fps with the 180 gr JHP.

More updates to follow

Posted: 10/17/2006 8:55:22 PM EDT

[#1]

heh, that looks mean!

even a lil like a mini 458 SOCOM

Posted: 10/18/2006 3:37:31 AM EDT

[#2]

That would be a .502 Thunder Sabre case, necked to .40 cal. It could be made to run in an M1 Carbine as well.

Tony Rumore
Tromix Corp

Posted: 10/18/2006 4:02:10 AM EDT

[#3]

Nifty!

Given the rim diameter, wonder if it could be made to run in a .30 Carbine AMT Automag III?

Posted: 10/18/2006 7:19:06 AM EDT

[#4]

That would be a .502 Thunder Sabre case, necked to .40 cal. It could be made to run in an M1 Carbine as well.

Now that would be very cool Tony! I figured it would run in the AK as well! Ron

Posted: 10/18/2006 2:21:02 PM EDT

[#5]

Marty,

Do you know how many will fit in a mag yet?

Posted: 10/18/2006 5:13:55 PM EDT

[#6]

Indeed the 502 TS case as Tony stated. Same diameter as the SOCOM, so same mag capacity. WOuld be great for the AK, not sure about the AMT 30 Carbine (30C is .356, this is .445 rim size)

Fired 4 rounds today, ~30 gr Win296 under the 180 JHP. Oversized gas port, high pressure, shortened gas system (old barrel, don't ask). Brass was ejecting hard enough to cause injury to bystanders (had there been any). Flat primers, big muzzle flash, snappy recoil. Bolt is just fine, rounds fed perfect. Did not get velocities, too much rain.

Posted: 10/19/2006 5:06:09 AM EDT

[#7]

Sounds like the bolt will hold up

Hopefully you can move the gas block/front sight forward to reduce gas flow. I wonder if this will shed the jackets on the 135's? Cant wait to try this puppy out! Ron

Posted: 10/19/2006 1:42:07 PM EDT

[#8]

Quoted:
Nifty!

Given the rim diameter, wonder if it could be made to run in a .30 Carbine AMT Automag III?

Given the diameter of the case, you'd need one of the AMT Automag V.

Posted: 10/19/2006 3:53:21 PM EDT

[#9]

I did something similar for a TC barrel once...

If I remember right, we held the 400 corbon dies 0.200" or 0.250" long.
Basically a 38-40, but stronger brass and therefore higher pressures.

That little 40 caliber hornady blackpowder bullet is wicked.

Posted: 10/19/2006 6:52:14 PM EDT

[#10]

oooooh, must get some of those bullets. Barnes makes a 45 caliber muzzle loader combo of a sabot and a 190 gr XPB looking bullet. Ty also said they have a 155 gr XPB. No jacket to shed ... but he said the petals might break off - not a problem to me - multiple wound channels ....

Randall - did you get my IM re 6.8 pistol barrel?

Posted: 10/20/2006 6:57:55 AM EDT

[#11]

That Hornady + the Barnes MZ bullets will be awsome in this round

Ron

Posted: 10/20/2006 7:24:15 AM EDT

[#12]

Thompson/Center also has a polymer tip 200 grain .400 sabot projectile. They also sell 200, 250, 300 grain .451 bullets of similar construction. I imagine they are simply rebranded Hornady. They are a bit cheaper on the local market and they have yellow plastic instead of red.

David

Posted: 10/20/2006 7:31:37 AM EDT

[#13]

Posted: 10/29/2006 4:40:07 AM EDT

[#14]

Marty, any more progress on this? Ron

Posted: 10/29/2006 2:13:48 PM EDT

[#15]

What about resizing a br case in the 400 corbon die. You would probably have to neck expand thie first time. I don't know if this would make the necks too thin.

Posted: 10/29/2006 7:15:50 PM EDT

[#16]

Quoted:
Marty, any more progress on this? Ron

Not as of yet. Trying to get your 40 Super finished, then will turn to this one.

Posted: 10/29/2006 7:17:13 PM EDT

[#17]

Quoted:
What about resizing a br case in the 400 corbon die. You would probably have to neck expand thie first time. I don't know if this would make the necks too thin.

Actually, one of our overseas colleagues makes a 40 BR, with lathe turned solid bore rider HPs. It looks like a 300-221 on 'roids. Sucker is dead nuts quiet and PacNor makes a custom 40 cal barrel twist for it ...

Posted: 10/30/2006 6:12:35 PM EDT

[#18]

How much velocity does a 40 super gain over a 10mm?

Posted: 10/31/2006 3:22:59 AM EDT

[#19]

Dont have my data with me but it averages 200fps faster than the 10MM. It's like the 10MM Magnum from a 6" brl. In a 12" brl it should be interesting. I will post some real #s when I get home. Ron

Posted: 10/31/2006 6:53:55 AM EDT

[#20]

Ron's right on. About 200fps faster then an "original" full power 10mm loading. The 10mm loadings these days are so friggin watered down, it's barely more then a 40 Short & Weak. But in the original loadings, launching a 170gr bullet at 1,350fps, you'll see the Super put another 200fps on that.

Posted: 10/31/2006 1:21:37 PM EDT

[#21]

Thanks Tony! Couldent of said it better. The 40Super will push a 165g HP @1600fps from a 5" brl. I hope to improve on that with a 12" brl! Ron

Posted: 10/31/2006 11:00:31 PM EDT

[#22]

I wonder what could be done with, perhaps steping up to a .308 sized platform, ashort fat cartridge using the projectiles designed for the .408 Chey-Tac. As I understand it the Chey Tac .408 projectiles are incrediblly well designed, low drag, etc. So, yeah, a short fat cartridge out of an AR using the .408 Chey-Tac projectiles. Should be very capable.

Tsh77769

Posted: 10/31/2006 11:14:39 PM EDT

[#23]

Quoted:
I wonder what could be done with, perhaps steping up to a .308 sized platform, ashort fat cartridge using the projectiles designed for the .408 Chey-Tac. As I understand it the Chey Tac .408 projectiles are incrediblly well designed, low drag, etc. So, yeah, a short fat cartridge out of an AR using the .408 Chey-Tac projectiles. Should be very capable.

Tsh77769

And very expensive

Posted: 11/1/2006 6:33:13 PM EDT

[#24]

Quoted:
I wonder what could be done with, perhaps steping up to a .308 sized platform, ashort fat cartridge using the projectiles designed for the .408 Chey-Tac. As I understand it the Chey Tac .408 projectiles are incrediblly well designed, low drag, etc. So, yeah, a short fat cartridge out of an AR using the .408 Chey-Tac projectiles. Should be very capable.

Tsh77769

Those low drag bullets come at a cost - they are long, thus eating up powder capacity. Note that to fit the 50 BMG BALL bullets on the 500 Phantom, the case is 1.5" long AND the largest diameter case that fits through the extension of the AR-10 series. So the CT bullets will have to be seated WAY deep, likely deeper than the ogive permits. Then the issue that the CT case is too large in diameter, it will not fit...

Best bet is to go with a far more readily available bullet of similar higher BC - the 300 SMK in .338. Use the largest case suitable, adjust it to fit the AR platform and ... oh darn ... it's our .338 Rhino

Posted: 11/1/2006 9:26:17 PM EDT

[#25]

Well, it was jsut a quick thought that immediately jumped to mind when I was thinking about 40 caliber extreme AR's.

Oh well.

Tsh77769

Posted: 11/5/2006 2:17:50 PM EDT

[#26]

Marty, do you know how the guys running the 40 br are modifying the mag, or are they using some other mag with an adapter.

Posted: 11/5/2006 2:21:01 PM EDT

[#27]

I volunteer for RnD. I have a build going right now just begging for something cool, haven't bought any of the caliber dedicated parts yet. Im me for address on where to send the bolt, barrel, gas tube, and hang guard to. Along with oh, about 100 mags with a few thousand rounds of ammo.

Posted: 11/5/2006 7:09:12 PM EDT

[#28]

Quoted:
Marty, do you know how the guys running the 40 br are modifying the mag, or are they using some other mag with an adapter.

Integrally suppressed bolt gun with lathe turned bullets

Posted: 11/10/2006 6:58:11 AM EDT

[#29]

Ron/tony thanks for the 40 super info. I was wondering how it compared to the double tap 10mm, but it looks like it smokes it.

For reloading, is the super the same profile as the 400 corbon or are they different. I know the brass is different, but is it even available. That is a lot of power in a compact little round.

Thanks,

Posted: 11/11/2006 6:13:21 AM EDT

[#30]

tk064, the 40super was available at Starline about 6mos ago. I ordered 1000pcs. Contact them, they should still have some. The 40super is the 45win mag necked to 40cal with a small rifle primer, so if brass is unavailable you could use the 45win mag brass. Are you are wondering about using 400corbon dies? I hear someone does use 400corbon dies to reload this(but dont quote me on that). I got lucky & picked up the last set of dies midway had! They are redding so I would give them a call if interested. I was researching info for my 40X idea & came across this round & had to put in a AR! So I got Marty to cut me a brl for it. Much over 12" & the gain in velocity was minimal. Hope this helps, Ron

Posted: 11/11/2006 10:05:17 AM EDT

[#31]

Thanks for the reply. I have a set of 400 corbon dies, that is why I was inquiring. I also have some 45 winmag brass somewhere so that is interesting.

My inquires were originally about if you get much more than a 10mm. I have a bunch of 10mm stuff, but getting a couple hundred fps more is pretty substantial. One 10mm ARguy (shindawia6)
posted that he was getting close to 425 fps faster out of an AR with doubletap ammo. Given that, I did not know if it would be worth it to try the 40 super or just the 10mm. I just ordered a chrono and some doubletap and figured I would check some velocities our of a delta with and without a mechtech on it.

Thanks,

Tim

Posted: 11/11/2006 10:09:03 AM EDT

[#32]

Looks nice, but couldn't you have picked a less cliche name? If you do a .40 "tactical" or .40 "SPECOPS" next, I'm calling the good taste police.

Posted: 11/11/2006 5:30:52 PM EDT

[#33]

Quoted:
Looks nice, but couldn't you have picked a less cliche name? If you do a .40 "tactical" or .40 "SPECOPS" next, I'm calling the good taste police.

But I love cliches!

I guess you're right but I am running out of original names, heck, Uncle Sam is even stealing some of mine ... I came up with this nice 7mm round made from shortened Carcano brass and was trying to find a name. Short Carcano ... Carcajou ... nah ... Caracal ... nah. Car ... Short ... Short Car ... Scar! SCAR! That sounds cool. Next thing I know, they are running some program called SCAR ... go figure ...

Posted: 11/12/2006 3:32:45 AM EDT

[#34]

You could call it .400 Piledriver, .40 Loki, or 10mm Mjolnir(Thor's hammer). No need to do a .40 Tactical, the .30 Herrett Rimless Tactical already did the honors.

Posted: 11/12/2006 5:03:53 AM EDT

[#35]

tk064 , Post your results! I also have a 10mm & would like to see your findings. Ron

Posted: 11/12/2006 5:05:25 AM EDT

[#36]

Quoted:
You could call it .400 Piledriver, .40 Loki, or 10mm Mjolnir(Thor's hammer). No need to do a .40 Tactical, the .30 Herrett Rimless Tactical already did the honors.

That would be Mjollnir, and the O has two little .. on top

How about 40 LSFB - Little Short Fat Bastard