The 224 Valkyrie is based on the 6.8 SPC case. Does anybody know if it is possible to chamber a 6.8 SPC round in a 224 rifle (like 300 BLK & 5.56)?

I am all in for the 6.8 SPC and considering building a AR platform rifle in 224, but not if the 6.8 could be inadvertently chambered in the 224.

Generally when a cartridge is created from a parent cartridge, the shoulder is positioned in such a way as to preclude chambering the larger bored ammunition in the smaller bored chamber.


I looked around for a picture of the two side by side, and couldn't find one.

They gave the 224 a nice long neck to hold those long bullets, I would expect the shoulder to be pushed back and blown out with less taper than what the 6.8 has, but again, I am just speculating.

No, the Valkyrie round is necked down to 0.224 (22cal) from the 6.8’s 0.277 diameter.

The 224 Valkyrie shoulder is pushed back slightly a few thousands. It will not be possible to chamber the 6.8 SPC round in the 224 Valkyrie chamber.

I had a chance to shoot the 224 Valkyrie this weekend in a JP rifle. Recoil was the same as a 556/223.

No, you can not chamber a .277 round in a .224 barrel. It would not seat and allow the bolt to close.

The OP's question isn't off the wall -- given that putting a 300blk round in a 223 rifle wasn't supposed cause a kaboom. And yet there are a few documented times where that 300blk round was somehow torched off in a 223, even though it didn't really "chamber" in the rifle.

I don't know the answer, however.

It "works" with the .233 / 300 because they're not the same case. The 300 Whateveryoucaretocallit is based on the .221 Fireball, a shorter case.

So as long as the 224V and the 6.8 are about the same length, it shouldn't be possible.

You may be able to put a 224V in a 6.8 but that will be uneventful.

I would expect Federal would consider and design against accidental loading of a 6.8 round in a 224 rifle, but just wondering if it was real world possible. The rounds share magazines and bolts, so only the barrel chamber stands in the way.

Hopefully you can't load a 6.8 in the .224 Valkyrie. But a .224 Valkyrie round drops right in a 6.8.

Yeah but all that will happen is it will sound funny and you'll have a new 6.8 case that probably has a short neck.

Nearly one year on, I still have not found where anyone has physically confirmed the fact that a 6.8 SPC round will not chamber in a 224V.

No. It won't chamber for the reasons stated above. Since my last post, I acquired a .224 Valkyrie barrel and built mine. I tried a 6.8 round in a .224 Valkyrie Case Gauge. It doesn't fit. The 6.8 sticks out of the Valkyrie case gauge between 1/4-1/2". Not even close to chambering. Unable to show via photo on this site. But sent a photo via email.