Waddya mean gas guns dont shoot?

[xsn10s]

I only have adjustable gas blocks on my piston ar-15's. I've always use the smaller steel gas blocks for what ever diameter barrel. I grind a dimple for the set screws so the blocks won't move.

I have an Adams and two Superlative arms rifle length pistons kits and both of them have failed out in the wilds from going out of adjustment after hundreds upon hundred of rounds. Then you have muck with them if they haven't lost a screw or something

adjustables are just another point of failure compared to non adjustable. You just have to put some thought and change the weights of items to get YOUR ammo to cycle right and all the rounds landing out there at 2:30. No reason to use an adjustable. spend you money on SS match grade barrel and specify smal diameter gas holes with rifle or rifle + two inches

So if I wanted to shoot 75 gr ELDM's through a modified mag and magwell what diameter gas hole would you suggest?

 

[C-130 Dude]

So if I wanted to shoot 75 gr ELDM's through a modified mag and magwell what diameter gas hole would you suggest?

Something in the neighborhood of .089 or so. Lots of manufacturers guns are close to that. You can always go larger if needed.

 

[budlight]

All of my barrels are .067 - .078 with rifle length and + 2. My disclaimer is that I reload with the slower powders and at higher psi. like 5.56 reloading charts with cfe 223 leverrevolution, power pro 2000 mr, h414

 

[budlight]

Something in the neighborhood of .089 or so. Lots of manufacturers guns are close to that. You can always go larger if needed.

My idea has always having a less violent ejection cycle. I don't care about also slowing the rate... It's a semi auto not full auto. Before i ever built my first one I was looking at a friends Colt carbine 16 inch and the front of the buffer weight was all beat up. With only a few hundred rounds through it. I started thinking about how to fix that and I started doing research on the gas tube length/VS pressure wave/VS gas hole diameter. So I ordered a 20 inch barrel and ask for a rifle length .0067 hole with the understanding that if I didn't like it I could have the hole enlarged if necessary.

Another thing that I have played with is enlarging the air hole on the buffer tube back end. I reasoned that the buffer weight was compressing air on the cycling. Barely enlarging the hole helped with light springs and weights.