400 Blk ever happen?

[maw1777]

So sticking a 762 in a 556 cartridge worked out great with minimal parts changes. Would a 40 cal in the 762 work just as well? Modify an AR10 and you'd have a pretty awesome hunting gun without the over-power of current 40 cal options or 338 magnums. Then again the 458 socom and 450 bushmaster never took off.

[Ridgerunner665]

40 might be a bit much for that case...but 33 to 35 would work.

The 358 Winchester is a fine round, been around a long time...just never caught on...its just a necked up .308.

I have a Browning BLR in 358 Win.

[jmk]

So sticking a 762 in a 556 cartridge worked out great with minimal parts changes. Would a 40 cal in the 762 work just as well? Modify an AR10 and you'd have a pretty awesome hunting gun without the over-power of current 40 cal options or 338 magnums. Then again the 458 socom and 450 bushmaster never took off.

though interesting, couple reasons i really doubt it, esp if you're talking about a .40 cal pistol bullet(?)

these things are designed for like 1200fps. out of a 7.62 case they'd be much, much faster - like hyper-velocity.

due to that velocity, they'd probably act like one of the very light varmint bullets out of .223 (i.e., extreme fragmentation and very shallow penetration). that has potential merit, but would make an extremely expensive prairie dog round...

unlike blackout, they're not rifle bullets, so would lose velocity quickly, limiting range.

the appeal of .300blk, socom and .450bm is that they fit in the standard (and nearly ubiquitous) AR size envelope. huge benefit not only from user interface & parts commonality, but also extending to support equipment like mag pouches, etc.
.300blk takes that a (giant) step further and also uses "standard" .308 bullets, 5.56 brass, and unaltered BCG & magazines. this in addition to it's incredible ballistic versatility...
it's a case study in "what's the best we can do with what we already have."

the 7.62 AR is a much rarer beast, so the COTS ratio is much lower off the bat. add in the AR10/SR25 split and the probable need for specialized .400 bullets, and you've probably moved out of the serendipitous sweet spot that is .300blk (and certainly the rest of the AR-envelope cartridges).

[High Tower]

Google JD Jones, SSK Industries, or the Whisper lineup. He's got the 338 Whisper and I believe the 416 Whisper. Same concept as the 300 Whisper/BLK but bigger.

[Agnostic]

Or .338 Spectre. 6.8 spc necked up to .338 (I think). I don't know much about the cartridge, but I think it will throw the lighter .338 bullets at supersonic speeds.

[redtazdog]

Google JD Jones, SSK Industries, or the Whisper lineup. He's got the 338 Whisper and I believe the 416 Whisper. Same concept as the 300 Whisper/BLK but bigger.

JD Jones has a made whisper in damn near every caliber, many are just not on the ssk website.

[Javelin]

As if 300 blk ammo isn't hard enough to source.

[khc3]

There's the 338 Spectre from Marty TW, the guy behind the 458 socom.

[Mr blasty]

There is the 44 auto mag but that's a pistol round

Sent from my SGH-T999 using Xparent BlueTapatalk 2

[Grand58742]

And what would this magical .40 rifle round do that a current .308 offering won't do? Factory grain weights from 110-180 grains that generally give a good spread of bullet designs. And really from all accounts there is nothing in the lower 48 that can't be taken by a .308 as long as the grain weight is correct for the hunting application.

Or you could do some homework and come back with:

.338 Federal

Which has some pretty good ballistic data as well as being built in an auto platform by DPMS and Armalite. And probably could be built on an AR-10 receiver by a custom guy since the barrel is the only thing needing replacement. The .338 Federal was built and designed as a big game cartridge to fit into the .308 sized actions and autoloaders.

Other than the obvious "wow, neat, let me shoot it just to say I did" factor and giving the standard gun rags something to drool over, claim its the next "military issue cartridge!" and continually write about for a couple of months, there really isn't a justification for a .40 on top of a .308 case. Neat? Maybe, but not really something the market is looking for.

But if you want to make your own wildcat cartridge, go for it.