This may sound crazy...

[nfa1934]

This may sound crazy, but has anyone given serious thought to making an AR10 pistol? Would they be more or less problematic than the .223 as a pistol? Are there any issues with possibly raining on someone's parade regarding ammo availability (like how people are avoiding building 5.45x39 AK pistols)?

[JE3146]

Donno how strong your wrists are, but I know mine couldn't take it. If you want a hand cannon, try a 500 S&W :)

AR10 pistol though? Only problem I could foresee is they are VERY VERY finicky about their gas port location / size.

I know numerous people have custom built their AR-10's with gas blocks further down the barrel to create better reliability, and less carrier bounce from the high pressured .308.

Sticking a gas port on a 10.5" barrel for a .308 round.... donno.. just seems to me that carrier would be breaking apart after a couple hundered rounds...

[nfa1934]

I had fired the BM59 folder that I used to have with the stock folded. It wasn't really that bad (but only on semi, I wouldn't even think about that with the selector on auto). I don't think an AR10 would be much worse.

Is the AR10 carrier more delicate than HK internals? The HK51 is about the same barrel length as an AR10 pistol would have and they don't seem to have parts breakage problems.

[JE3146]

I think the problem lies with the gas impingment system not regulating the flow of gasses. Too much gas = too much force.

I've never seen the internals to the HK guns.. are they gas piston or impingement?

[Epinephrine]

They are in fact neither except for the G36 which uses a gas piston

The most notable example is the G3. It uses the roller locked delayed blowback system.

Theres a 2 part bolt (1 light part and 1 heavy part) with two rollers. When the gun fires, pressure forces the casing back against the bolt and the rollers lock into the barrel, making the heavier rear bolt move back. When pressure drops to a safe level, the rollers disengage and allow the entire assembly to move rearward, ejecting the spent casing and recocking the gun.

Since 3 tons of force contacts the 1" bolt face in an even pattern, you dont have to worry about it ripping itself apart. With the AR, 3 tons of force would be contacting the tiny 1/4" carrier key, so multiply that by god knows what and figure in that all of that is on top of the carrier, not the front,you have one hell of a load one side of that carrier.

That may not be a problem with a 7.62mm with a gas port 13" or more from the carrier or a 5.56mm pistol with a port 4" from the carrier, but cut that down to say, a 8" barrel like on most AR pistols, moving the port 4" from the carrier and add in a 7.62 and you got a lot of force in there.

HERE IS (http://www.buffertech.com/stores/1/webpage_cfm_W7.cfm) an interesting movie that explains quite a lot about the forces in a G3. Look at the very bottom of the bolt when the gun fires and you will see the heavy rear part go back about 1/2" and the pull the light front part unlock from teh barrel.