357 rimless magnum AR
 

I know, it's crazy but why not! I'm looking for positive input on wildcatting the .223 by reforming it to take .357 caliber bullets.

Idea is to only have to change your ar upper. Also, having reloading options if you have .308, .45acp, .357 & .223 bullets & cases. Kind of a survivalist reloading idea: I hear you can cutdown .308 brass to 45acp, put .308 bullets into .223brass(7.62x40), .223 bullets into .308brass, .357bullets into .308's (.358win) & 45acp's, granted there's more to it than just ramming lead into brass but has anyone heard of this .357AR idea?

thanks

Re: 357 rimless magnum AR
 

Why not get one barrelled in .357 SIG?

BTW... I don't think a .223 case has enough room for a bullet of that diameter.

Re: 357 rimless magnum AR
 

The base diameter of a 223 is .376" and the actual bullet diameter is .358 but that doesn't leave enough room for the case wall. Usually brass is around .012"-.014" thick. What it boils down to is the finished case would be bigger in diameter at the bullet end than the base and that won't work.

The 300 Whisper is a fairly successful cartridge necking a very similar cartridge to the 223 up to 30 caliber but it would be pushing it past diminishing returns to kick it up to 357. If you want an AR upper with more bite, what's wrong with the 6.8 mm?

Re: 357 rimless magnum AR
 

there are medium bore cartridges popular in the ar15, such as 6.5 grendel, and a 6.8 mm version also i think.
My comment is that it is very hard to envision a scenario where the world runs out of .223/ 5.56 There are likely more billions of these cartridges in existence than any other manufactured item.

Re: 357 rimless magnum AR
 

Thanks all, I just got excited about the idea and was looking at all of the other wildcats that I didn't think to stop and look for the obvious (no wonder nobody is doing it).

Re: 357 rimless magnum AR
 

Interesting. I really don't know how that would work, but I find wildcats, very interesting, if you've got the time & $. My buddy at work did a wildcat of a 17 Remington/22 hornet. Very, very fast, but I would think barrel life would be rather limited.

Re: 357 rimless magnum AR
 

I don't think it is all that expensive to do your own wildcat. No more than a couple hundred to have a chamber reamer made and a roughly equal amount for some dies.

Re: 357 rimless magnum AR
 

Cooper did his 9mm Super Magnum wildcat and the Winchester 9x23 is currently produced.

Then there was the Winchester 1907 .351 carbine.

Re: 357 rimless magnum AR
 

Instead of using the AR15 as the base rifle, consider going to the AR10 as the base rifle.

That way you START with the .308 cartridge.

I can't say for sure, but that would be a much easier conversion. That's just a guess on my part though.