Ammo causing short stroking?

[The Soup Nazi]

So I stripped down my Stag 2HT day before hitting the range, lubed it up, took it out. While sighting it in, the last round would not hold the bolt back, but everything worked fine. Then, when I took it out to the steel plates (AND I think it might be worth mentioning that I switched bandoleers since my current one was almost empty.) Then I had more problems, though they didn't ALWAYS occur. In every instance, the rifle succeeded in ejecting, but in some cases, a new round was not chambered, and at one time, the bolt got caught on the casing, though this was easily remedied by pulling the bolt all the way back while the extractor did its work. I was shooting Radway Green (which is as old as I am, 1989-1992 surplus). From what I heard it was a little underpowered since it was designed for the British SA80, but it functioned perfectly with the same lower and someone else's upper assembly.

One thing to note though is that when I used some of Sardaukar's American Eagle .223, it functioned flawlessly. Did I just happen to get a bad bandoleer out of a bunch, since I've gone through about 1400 of similar ammo in an SU-16 and another OLL set up with no problem?

[rkt88edmo]

Gas key a little loose? Gas rings have the gaps aligned? It sounds like the ammo, or some combo of the ammo and upper.

[The Soup Nazi]

I think it is the ammo, after all, if the casing starts to radiate vibrant colors, I would suspect it a little, although it was structurally sound (no deformed necks or other parts of the casing, didn't read about any ka-booms on arf.com)

[C.G.]

Gas key a little loose? Gas rings have the gaps aligned? It sounds like the ammo, or some combo of the ammo and upper.

+1. However, I have this problem with Wolf Performance ammo on my Ar-15, checked everything over, and still does it. Has had no problems with any other ammo.

[RainierArms]

It's definitely the Ammo. Stay away from Radway green.

[jdberger]

It's definitely the Ammo. Stay away from Radway green.

What does that mean? "Stay away"?

The ammo is known to be a little underpowered, and there isn't much that you can do for that except find a rifle that it likes - or trade it for ammo that your rifle likes.

I've a similar situation with SA 7.62. My M14 hates it - my FAL loves it. So I pay attention when I'm packing up for a range trip.

But "stay away"? It's not like the ammo is defective or dangerous, just a little underpowered.

[bwiese]

Soup,

I gather you & your dad are coming to the Shoot-N-Q. We'll have a debug session. I have a big jug of CLP and a bunch of known-good mags.

Are you running a fixed mag setup, or are you using a MonsterMan grip or U15 stock?

While I wouldn't jump on purchasing RG ammo, as it's a bit anemic, your rifle should really run OK with it.

There is a chance this could be due to a bit of magazine influence. If something's dragging/binding coming out of mag, this could explain your symptoms.

Do you notice any gouge marks from the magazine on your spent cases?

[SkyMag68]

Hey I was havin the same exact problem w/stag 2h durin campin trip..look lik it is under power..try other ammo it work fine..bought 680 rds(89' head stamp) from Vepr62 lik 3 wks ago..mayb he havin the same problem..

[tenpercentfirearms]

This sounds more like the bolt carrier issue Stag seems to have had in the month of April. If new ammo still causes it, send it back.

[stator]

So I stripped down my Stag 2HT day before hitting the range, lubed it up, took it out. While sighting it in, the last round would not hold the bolt back, but everything worked fine. Then, when I took it out to the steel plates (AND I think it might be worth mentioning that I switched bandoleers since my current one was almost empty.) Then I had more problems, though they didn't ALWAYS occur. In every instance, the rifle succeeded in ejecting, but in some cases, a new round was not chambered, and at one time, the bolt got caught on the casing,

Bolt overs - I've experienced this with a mag-locked lower and more so with Wolf. I went through everything including installing one of Denny's HD bolt carrier and bolt. The solution to the problem was to loosen the mag-lock to allow slight play with the mag to magwell.

If you have a mag-lock completely screwed down, install the spring and screw-down the mag-lock but leave a slight play. You will need to use the short allen screw, though. Better yet, just switch to the BB.

[Gunsrruss]

Springs...

On my M-14 I bought some of those new 10 round mags they have out. Well, the springs are either still for 20 rounders or cut down improperly. They are too tight and hang everything up. If you have 10/20 or 10/ 30 mags you might have problems.

[The Soup Nazi]

Well, again, new factory American Eagle DID NOT cause any troubles, it functioned perfectly. I've fired about 1000 rounds of Radway Green in other rifles such as the SU-16CA and other AR-15s with success. I really do suspect it was this particular bandoleer because the rest of the rounds from the can did work.

I really did sop down my rifle with CLP, and I am running on a fixed mag setup. I've used the lower itself (with the same mag) on other uppers with success with the same kind of ammo, so its either an upper issue or ammo issue. (I suspect it to strongly be the latter) I'm running the Bushie 10/20 btw, but I've managed to fit 10 rounds with no failures in that on another upper.

[sardaukar]

Come to think of it, Soup, your spent brass wasn't ejecting very far. Another symptom of bad ammo?

[The Soup Nazi]

Well, I think that was just because I was firing while prone, I'm pretty sure it went further while crouching or standing.

Edit to add: Even though I applied a generous amount of oil, I actually did have trouble pulling the charging handle back at time as if it got stuck on something (though I've had no trouble on other uppers.) Very recently I just almost soaked the moving parts in CLP/gun oil, and the fluidity that everything moves with seems to reinforce confidence that things should work well for Chabot on Saturday.

[C.G.]

Edit to add: Even though I applied a generous amount of oil, I actually did have trouble pulling the charging handle back at time as if it got stuck on something (though I've had no trouble on other uppers.) Very recently I just almost soaked the moving parts in CLP/gun oil, and the fluidity that everything moves with seems to reinforce confidence that things should work well for Chabot on Saturday.

Did you check for blown primers? Sometimes they get stuck in the strangest places and can make it difficult to pull the charging handle.