338-223

I want an ar15 barrel chambered in a .338 cal cartridge formed from 223/556 brass. not interested in anything else, just that. I am hoping someone has some ideas here, I need some help finding a custom AR15 barrel maker willing to make one for me. I tried SSK who made the 338 whisper #2, they refuse to do it claiming it will not function in an ar15 to which I say nonsense, but even begging them to do it saying I didnt care and just like to tinker they still said no.. Similar thing for the 338 thumper at BWEfirearms...he says it will function and cycle reliably, he has the reamer, but says there is no interest and so he wont make one for me which just left me scratching my head dumbfounded that a custom maker with the know how and tools who used to do it, won't do it. I am not trying to get it cheap, I just want one and have since I thought of the idea 5 or six years ago. no answer or returned phone calls from subsonichunter.com who also claims to make the 338 thumper. ar15barrels.com said he could, then found out he doesn't have the correct reamer so is unable to. I found a custom reamer at pacifictoolandgauge.com but I dont have a lathe or the space for one right now...maybe some day. i'd be willing to buy that reamer if a barrel maker or gun smith would be willing to turn it out for me, I am sure I could get a set of dies made from C4hd, but havent asked them yet, as I dont see a point until I have a barrel under way.
any suggestions on how to get what I want? I keep striking out. my wife and I are building an ar15 together and this is what we decided we wanted, unique, and fun to shoot, little recoil, easily suppressed and stuffing the largest caliber bullet a 223 case can handle inside it seems really cool to me, not to mention unlimited cheap brass....anyway I hope someone can help. thanks.

 

Cut and rechamber a 338 federal AR10 barrel?

Buy blank 338 bore barrel and ream it, install barrel extension and drill a gas hole?

Finish reamers can be used by hand once a rough chamber has been cut. They can also be rented, though i am unsure of availability of such an obscure round.

Other barrel makers to try: MGM, Green Mountain, Shilen, Ed Arthur Brown, Satern, Douglas

 

Try here

https://mdws.forumchitchat.com/mad-dog-weapon-systems-inc-558020

 

This may be of some interest to you that is readily available and uses regular dies and has more bullets available.

https://www.go2gbo.com/threads/357ar-max-rimless.263822/

 

OP MDWS has exactly what you are looking for. Its called the 338 Ghost I believe. AR-15 barrels and can do bolt action barrels for savage actions also.

IMO the best way to get ahold of them is to use Facebook and find the Facebook page call BD's crazy ass wildcats or something like that.

 

That one is a 6.8 spc case

 

Is it really? Now I haven't looked at it much, and they are always making more so I can hardly keep up lol.

 

It won't function RELIABLY. 350 Ledgend has enough problems in a AR that it's reasonable to believe a 338 would behave similar.

I can understand them not wanting to build something they're not confident in. Funny enough, I'm chatting with them over email about a project that they're saying doesn't work well.

 

Yes they did say "reliably" going back and looking at the email, but being a tinkerer/reloader I feel confident I can make it work. I found a barrel maker today that says they will do it if I send in a loaded cartridge. Easy enough, so I played around and settled on a 1.400 inch cut down 556x45 casing. My 11 year old daughter named it for me even though this cartridge has been done before, she wants to call it the "338 Stealth Mode" or 338 SM for short. I stuffed a Hornady 225 grain SST in one case and a Hornady 285 grain eld-m in another to send in so the barrel maker will cut the throats to accept either bullet. I drilled out a 223 trim die for the dillon rapid trim to eliminate the shoulder and allow enough space to cut down the 223 case to specs, so I can now make a lot of brass in a hurry. I used a regular 223 Hornady sizer die to size them down, for real production I will put a 338 expander button on the decapping rod. I seated the bullet with an RCBS 223 competition seater. There is plenty of neck tension to keep them in place, and they appear to be concentric though I dont own a concentricity gauge. I am doing a 16 inch barrel with threads on the end to accept my 35 caliber suppressor. From my reading about similar cartridges like the 300 BO it sounds like a pistol length gas system will probably be needed, so I am going with that and an adjustable gas block just in case.
I am sending the rounds in tomorrow and then its time to wait.

 

https://www.midwayusa.com/product/1023840599?pid=207758

Speer gold dot bonded bullets from the now discontinued 338 federal fusion load.

 

What bullets (weight/brand) do you think will expand, at the low velocities that cartridge will be making?

DM

 

So, you want something like the .350 Le'joke, but in one of the few bullet diameters even more expensive than .350. To make life interesting, it'll be almost shoulderless, and will have to headspace off the mouth of .223 brass.

You certainly have collected an interesting set of difficulties. I suggest that you specify headspace off the ogive, and call it the Triple Crown of cartridge design challenges.

 

I cast boolits and have a variety of 338 moulds, even hollow point ones. expansion will happen. i also read the sst's will expand at low velocity. it will give me something to tinker with and test for a while. its also making a medium sized hole anyway 338 isnt exactly small. pistol cartridges headspace off the case mouth, i dont foresee it being a problem. head spacing off the ogive, now that would be something....

 

10th edition of cartridges of the world has a "338-223 strait" under wildcat's . there's a little info there. It was intended for blowback actions, like the 1907 Winchester.

 

I see your set on a 223 case , but if you used a Grendal , 30 Russian case and set the shoulder back far enough to use longer bullets in AR mags , you would be able to headspace off the shoulder , and still have commonality in bolt head availability , and readily available brass .

 

And then there's always 9x39 which is already a "thing" with rifles chambered as such.

 

This is the Mad Dog Weapons Systems forums page
https://mdws.forumchitchat.com/?forum=645266

Lot of original AR-15 wildcat stuff, note the 350 AR, it is the original 357 Super
Mag Rimless, copied and called the Legend, the original developer is on the site.The Yeti, is another 35 cat.
The MGP guy on the forum is the 358 MGP guy.