Barrel Extension question

[nekshot]

The ramps on the extension are to line up as the cartridge comes off lifter, correct? In other words if I do a single stack something then it gets one ramp? Are there good and bad extensions? Where can you get them and be confident they are good. The barrel extension is what the bolt locks into. Any no no's in that area? Forgive my ignorance of these mighty matters but searching utube can be almost a waste between the vocabulary challenged 900 word base level with the fundamentary words starting with a F ! Yup, I am a old conservative and starting to feel proud of it!!

[KenH]

By "barrel extension" you're referring to the extension for an AR15 type barrel? I'm not sure I've ever seen those for sale. I'm not very knowledgeable about ARs. All I've looked at had the barrel extension installed in the barrel when I purchased it. "IF" I remember correctly, the extension is screwed in barrel to around 130 ft-lbs.

I'm posting mostly to keep this thread easy to find so I can see knowledgeable responses and maybe learn something.

Ken H>

[Der Gebirgsjager]

nekshot-- specifically what gun are you talking about? For example, the breech portion of a Remington 870 shotgun that has a square hole in it that the bolt locks into is called a barrel extension, but it's not something you can buy or replace as it is a part of the barrel. So specifically what gun are you wanting information on?

[Preacher Jim]

Brownells sells AR barrel extensions

[Moleman-]

There are different barrel extensions for different cartridges if you're talking about ar15 type barrel extensions. The quality does vary between manufacturers, but I don't think I've ever had a bad one. What cartridge are you looking at doing?

[Boolit_Head]

If you are talking AR's usually the extension comes installed on any barrel you purchase. The question does not make sense in the context given. Can you elaborate?

[Moleman-]

As to where to get them, I've bought them from: Brownells; Midway; Bat Machine; DPMS; Olympic; JSE surplus; occasionally available at CDNN; Tromix; Green Mountain Barrels (no longer will sell them); sarco (used one) and gunshows. I like the standard ones over the M4 cut ones if they're going to get modified but it also depends on what upper you have to match.

[nekshot]

I apologize for not providing enough info. This is ar 15 stuff.

Moleman- I was thinking of stretching the 7.62x39 using a 220 swift cartridge as the base. I still am thinking 358 caliber but needing to settle the barrel extension issue in my limited understanding.Since this post I read about the 300Ham'r and that is really tempting if I can swing the bucks for it.

[Moleman-]

Hadn't looked at the hamer because it can't be used in the DNR zone I hunt in, but it does look interesting. You can get a .473" case head size 22-250 bolt and extension for an ar15 from Olympic that is good to 60Kpsi for a 473" case head size. The only bad thing then is the magwell length unless you get their special lower and stupid expensive mags. Used one of those bolts/extensions for my 44x1.8" AR15 which works fine with a standard magwell length. It's the rounded lugged bolt/extension in the pic next to a standard extension and 450BM/458socom bolt. They also have the WSSM bolts and extensions, haven't used the WSSM setup yet.

[nekshot]

Hadn't looked at the hamer because it can't be used in the DNR zone I hunt in, but it does look interesting. You can get a .473" case head size 22-250 bolt and extension for an ar15 from Olympic that is good to 60Kpsi for a 473" case head size. The only bad thing then is the magwell length unless you get their special lower and stupid expensive mags. Used one of those bolts/extensions for my 44x1.8" AR15 which works fine with a standard magwell length. It's the rounded lugged bolt/extension in the pic next to a standard extension and 450BM/458socom bolt. They also have the WSSM bolts and extensions, haven't used the WSSM setup yet.

I wish I lived down the road from you! However after reading and looking up Bill Wilson on the 300 Ham'r I think all of my frustrations with limitations of shooting 300 yds can be eliminated with that cartridge. All I want is a super light gun with scope and if 30 caliber than I want to shoot the 130 gr speer or 125 sierra 2700 fps. I can do that with the Ham'r. That would suit me because then I would have my 223wyde, 300BO,and the 300 Ham'r. I would keep the x39's to play with. Boy would I be happy in my playpen or what!!

[popper]

30 hammer, basically a 7.62x41WT? 12 twist. 25gr of H110? Looks like you could just barely make from a 223 rem without getting into the neck. I got to 39 before I got into the neck and never could xpand the neck without splitting. Guess one could try a 243 xpander at first. He uses the really short neck to get powder space but doesn't shoot cast. & uses high BC bullets. Just a little less performance than the 30/30 FTX. 308 AR10 works for me.

[bruce drake]

look up the 30 Herrett Rimless ARs. The cartridge is built off a trimmed down and necked up 6.8 SPC Cartridge.