S&W Tactical range report and ?

[Bartholomew Roberts]

I did call S&W today. Talked to the AR person. Nice guy. From what I gather from him I might have way too much lube on mine. I am going back to the range Saturday, after I have cleaned it and oiled it to his recomendations. I

sigma40ve - the S&W rep is suggesting that you have used so much lube in the chamber that it is contributing to an overpressure problem (which can also make the rifle short stroke). I think he is probably wrong on that assessment since even if you had lubed the rifle sloppy, the first few rounds would be the only rounds where a problem would appear. After that, the lube would be blown out/burnt up and function would be normal.

However, it can't hurt to try. I would plan on returning the rifle though.

I apologize for intruding in your thread. Let me just say I have worked on the AR15 for the past 12 years, and I have seen the bolt ring issue cause problems.

Redhat, since the bolt rings move with each shot, I am curious how you determined that the bolt ring issue was the source of the problem? Would you mind explaining for me exactly what you saw and what other steps you took to rule out more common causes of the same symptom?

 

[Redhat]

Redhat, since the bolt rings move with each shot, I am curious how you determined that the bolt ring issue was the source of the problem? Would you mind explaining for me exactly what you saw and what other steps you took to rule out more common causes of the same symptom?

Sure,

On the line when we had a M16 short stroke, we checked th bolt rings first. When I found them aligned incorrectly, I adjusted them. If the problem went away, we carried on. If it didn't we looked to other things as you mentioned (carrier key, gas tube looseness, worn rings).

 

[sigma 40ve]

D**n,
I hate to make this thread sound like the S&W Tac saga but, I can't wait for the S&W return label to come.

I cleaned and oiled it per the reps instructions. I went to the range today. I had 1 mag loaded with Guat 5.56 surp, it ran 8 rds then started short stroking. After that I tried Wolf/Prvi Parti 5.56 and it short stroked every rd, then I switched back to Guat, every rd a short stroke. The Fiochi 223 I brought ran perfect, after that. I tried some WWB 223 that was made in Isreal, it ran perfect, the 5.56 just won't run in this rifle.

I can't wait to get this rifle back to S&W for their try out and input.

 

[Redhat]

And this gun says 5.56mm cal on the side of the receiver? I think you may have a chamber problem as was previously mentioned.

Hope you get it fixed soon.

 

[Bartholomew Roberts]

Make sure they understand that your problem is with 5.56mm ammo and that .223 SAAMI ammo runs just fine.

Sounds to me like the hotter ammo is creating more pressure than it should (probably because it is a shorter leade .223 chamber) and the empty case isn't shrinking from the chamber walls. The bolt is trying to pull the case while it is still stuck to the chamber wall and is spending all of its energy on trying to unstick the case. Finally the excess pressure in the chamber reached normal levels and the case extracted normally; but by then the bolt had already used up most of its juice by then and so it short-strokes (which is usually a case of too little gas or leakage).

 

[mec]

My bushmaster Preditor doesn't feed with wolff or privi. Feeds with everything else-factory or handload-that I've tried. Liikes the cheap S&B ball. don't know why the other eastern european stuff doesn't feed I clocked the privi and fund the velocities in the mid-high 3100s (55 gr ball) and just as consistent as other rounds.

 

[Bartholomew Roberts]

Some of the Privi Partisan stuff that Wolf imports uses a different powder with a burn rate that is different from M193. It produces M193 velocities; but apparently it doesn't hit the same pressure curve as M193 and some rifles have difficulty with it as a result. I don't think that is the issue here because the Guatemalan is typical M193-style ammo and it isn't working either.

 

[model4006]

any update on this? what happened after smith got the rifle back? did they take care of it?