Didn’t turn out too bad. I am happy with it. The 190 gr match ammo thumps your shoulder a bit. I might try an adjustable gas block. I did open the gas port up a little. With the short barrel I was seeing muzzle flash through the scope even w/the flash can on the muzzle break. That’s on a bright day and not in the shade. I will have to shoot it at night without the flash can sometime.
“Only fits Sig Sauer 716 rifles. Will not work with any SR25 or AR10 platform.”
I’ve already bought all the rest of the parts for DPMS LR308 pattern. Oh well.
What size gas port did it come with? I’m probably going to cut and reprofile a barrel with rifle length gas system down to 10.5" and a carbine length gas system.
These work just fine. You just need a custom gas tube. Several people over on AR308.com have built these. The Sig was a piston gun. We are making impingement guns with the barrel. White Oak Armament makes custom tubes. Not sure what the gas port was. 1/16 bit was too small and 5/64 opened it up just a bit. I am more interested in the gun functionality than recoil.
Package was waiting on the porch, when I got home. I haven’t installed it in an upper, yet, but holding it next to a barrel with a carbine length gas port, it looks like the gas port location is the only oddity, and it’s in a spot that should be covered by the gas block.
After testing the fit with my upper receiver and bolt carrier assembly, I think I’ll cut it to the 10.5" length I wanted, recrown and thread the muzzle, then drill a new gas port at the correct location.
Thanks again for the info! That cuts a lot off the cost for this pistol build.
Just curious are you going to have enough dwell time to cycle the action going that short? I know my FAL pistol had a 8in barrel but that was a piston gun. Pretty sure there is a reason there are not a lot of really short ar style 308’s on the market. If you go with a pistol length gas system you will probably need a custom made gas block. I’m not saying it wont work this is just some of the potential problems i see.
The standard location for the gas port on a carbine length gas system is a little over an inch closer to the chamber, than where Sig put the gas port on this barrel. That should help with any issues from cutting two inches off the barrel.
If it doesn’t work out, I’m only out $49, which is less than I spent on some other projects that didn’t go as well as I had hoped.
Hi @shooterrex
Can you please take some more pictures of this build?
I really want to do one of my own.
If you could also let us know the length of the gas tube you had ordered.