RAM2940

Could someone explain the video above, I thought as the last round in the mag was fired that the bolt locks back on the bolt catch, not the mag. Why do you want the bolt holding back on the mag.

I only have the one 10 round PMAG.

I got back onto the issue, the Wilson combat barrel came with a .071 gas port, so I drilled the port out to .078 (5/64). With a non adjustable gas block, fired several rounds one at a time testing, and all rounds locked back. Recoil felt better. Now the next step is to get on a target and check accuracy and find what it likes.

Ive got a good amount of clp on complete BCG and inside upper receiver.

Yes, when you pull the charge handle back it will lock. This is my first Dpms 308 large frame rifle, feels like a lot of spring tension but I guess this could be normal. About 25 rds fired.

As the topic states, this is a 6.5 creedmoor, 20" Wilson combat barrel. I do have the armalite gas tube. Tried adjustable gas block, did not work, purchased a non adjustable gas block, it will chamber rounds from mag, but will not lock back on empty mag. Ejects shells okay. This is a rifle stock and aero precision M5 rifle buffer kit. Rifle buffer 5.3" long, Spring measures 12.6 with 39 coils, it is a lot stiffer than my AR15 springs. I was looking at slash's buffer table and wondering if the spring could be the issue. Link to M5 buffer kit that is installed. https://www.aeroprecisionusa.com/m5-308-rifle-buffer-kit

Check out sig sauer BDX scope package

I just pulled the gas block and only had half the hole open, readjusted and going to give it another try but it might be another 2 weeks. My rifle buffer is alittle over 5" and says it weighs 5.6oz. And the gas port is .071. The brass seemed to eject good but the neck was getting a flat spot.

This is the AP m5 rifle buffer kit I have: https://www.aeroprecisionusa.com/m5-308-rifle-buffer-kit

Okay, got out and fired a few rounds of federal non typical 140. Bolt will not lock back on empty mag, and will not pick up a round with round in mag. Shells eject to the 4 o clock . I have AP m5 upper and lower AP M5 rifle extension buffer and spring Armalite AR10 gas tube. verified Toolcraft BCG double ejector small pin SSA-e trigger 20" Wilson combat tactical hunter Going to pull the gas block and check alignment, but thinking it might be time to drill larger gas port. Any comments and suggestions.

In the second post on this thread, I wrote that the scratches happened when the round was cycled from the mag into the chamber, I got marks like on round #4 in above picture. When I dropped a round in a open chamber, no marks on round.

This is my first large frame AR. Have built several AR-15s. The rounds I cycled through look like #4 in your picture, long scratch lines on bullet. Stuken89 : Just finished assembly 3 days ago and cycled rounds yesterday. Could be a week before I have a chance to shoot. I was able to put a round in the chamber by hand, firmly pushed in, then tipped gun up and round fell out with no marks. I feel the bolt or ejectors are tight and might take shooting a few rounds. I have a double ejector bolt.

I just finished building a 6.5 Creedmoor and had same issues. Put a round in chamber with bolt locked back and round slides rite in and tip gun up and falls out. Slowly let bolt carrier go forward and would not close, pulled back and let it go and closed on round. Pulled bolt back and was hard to pull back but did lock back. Put round in mad and let bolt go into battery, picked up round and closed. hard to pull back and when round was removed brass and bullet had scratches. I believe at this time the scrathes came from the mag and feed ramps. Not near as smooth as my 6.5 Grendel. If you think you have a headspace issue, get a go gage and test, you can rent or buy.

Im going to try it first as is, I had a slr gasblock laying around so I put that on and we will see what happens. But it might take a week or two before I can shoot. Also I looked at Ballistic Advantage gas port sizes and they seem to be close to same size.

I took your advice and got a Armalite AR-10 gas tube, Ordered couple boxes of different 140 grain ammo, after testing will let you know how it went.