AR woes

[WC1911guy]

mtdawg169 do you think I should still get a H2 buffer?

If it's not broke don't fix it would be my unsolicited advice. It won't hurt to run a H2. I run a H2 in my 7" SBR and it's over 1000 rounds without a single issue. I haven't run it suppressed yet so who knows? Glad you got it worked out.

 

[mtdawg169]

Forgot about this post. So I went shooting a couple weeks ago and only brought the SBR and some tools because I wanted to tune the gas block thinking that maybe that had something to do with it. Got to the range and it shoots fine for the first couple of rounds and then went into semi auto mode. One of the guys at the range wanted to look at it and immediately he figured out what was wrong. Since I had the rail off he could see that the gas block and gas tube wasn't lined up with the port in the barrel. By the time he saw it l, it was total maligned but I'm guessing had been steady working it's way out of alignment which is why I was getting intermittent issues previous trips out with it. He aligned the parts and tightened everything up and it runs perfect now

Help me understand exactly what type of failure you had. Failure to extract or failure to feed?

I got my barrels dimpled that required set screws just in case.

Dimples make AR's happy! Seriously though, for a set screw gas block, a minimum of one dimple and preferably two is a must.

 

[BIGLEW]

I have an H2 buffer you are more than welcome to try out to see if it works for you.

 

[Lazarus]

I got my barrels dimpled that required set screws just in case.

You know I have to double check but I think the barrel might be dimpled.

The upper is a DSG/Seekins upper and its seems like its a good quality upper. I guess I translated the quality of parts to quality of workmanship/assembly because it seems to me like everything should have been tightened from the factory.

 

[mtdawg169]

So I start shooting and the first couple of rounds are fine, then I notice when I pull the trigger it felt kinda soft. Not a strong click bang, more like a thump bang. That happened twice and then the gun didn't fire. I think that might have been a live round. I extract the round, pull the trigger - click bang but the round didn't extract. The bolt was slightly back but it wasn't even far enough back to see the round...... I could fire the round but would have to manually extract it.

OK. I had to read the OP a couple of times to be sure I understood what was going on. I was mentally stuck on the original stuck case issue. Sorry, I'm still working on my first cup of coffee.

That's a pretty classic gas issue. Obviously due to the gas block shifting and cutting off the gas flow. As kaotiktribe mentioned, dimpling the barrel for set screws is strongly recommended. I'd also clean / degrease the screws and GB threads and apply red loctite to be sure they stay put.

On a 10.5 with a suppressor, I'd still recommend an H2 buffer. But if you're not having extraction issues, that's your call.

 

[Lazarus]

Help me understand exactly what type of failure you had. Failure to extract or failure to feed?

Dimples make AR's happy! Seriously though, for a set screw gas block, a minimum of one dimple and preferably two is a must.

This spans overall a couple range trips but basically the gun would fire but not extract the round. I would have to manually cycle the action. At one point I was shooting and it shot, extracted and chambered but as I continued to fire I felt the trigger get soft and then it didn't reset and stopped firing. I guess during that time the time was just bleeding off until it stopped functioning.

 

[mtdawg169]

You know I have to double check but I think the barrel might be dimpled.

The upper is a DSG/Seekins upper and its seems like its a good quality upper. I guess I translated the quality of parts to quality of workmanship/assembly because it seems to me like everything should have been tightened from the factory.

Any sign of thread locker on the original screws? Also, are the screw faces knurled or just smooth and concave? I've got some gas block set screws that are knurled and bite the barrel better. Let me know if you need a couple of replacements.

 

[rOmiLaYu]

 

[Lazarus]

Any sign of thread locker on the original screws? Also, are the screw faces knurled or just smooth and concave? I've got some gas block set screws that are knurled and bite the barrel better. Let me know if you need a couple of replacements.

I didn't look at the set screws for the gas block. I gave the gun to the guy at the range and he went back into their shop area and fixed it. I was thinking some locktite was in order and he didn't mention that he had used any so later on today I'll go back to it and add some. I have to see if my red is any good, havent used it in a while but I think I got some.

 

[mtdawg169]

I didn't look at the set screws for the gas block. I gave the gun to the guy at the range and he went back into their shop area and fixed it. I was thinking some locktite was in order and he didn't mention that he had used any so later on today I'll go back to it and add some. I have to see if my red is any good, havent used it in a while but I think I got some.

Go over everything. Check the screws, alignment, presence of dimples, etc. If it's not dimpled, send it to me and I'll take care of it for you, including dimpling and new grade 8 knurled set screws.