need some ideas..I am stumped

[DeanC]

I suppose it's possible that the shoulder has moved forward on those few cases. I don't know if your case gauge has a shoulder in it.

You could turn your die in a ¼ turn and see if that helps.

[Pinnacle]

Could be a short throat or an over long reloaded round. Bad combo

Assume that the headspace is good and the ammo is good - this happened to me last night - somerounds of the samelot were PERFECT - others would not feed.

Hummmm.

The mysterious AR.

[gunnerbmg]

[Speaking not as a reloader (there are other far more knowledgeable people), but purely as an engineer...

If all ammunition is trimmed and gaged, the trimming and gaging is correct, and the ammunition isn't altered (damaged) before use - the dimensions of the ammo should be within specifications. This would tend to point toward the mating dimension, the chamber....

Three thoughts come immediately to mind (not including thoughts of lunch).
•The chamber is slightly undersized and interferes only with ammo on the high side of tolerances.
•The chamber is "tight" and crud-n-such buildup bring it under tolerance.
•The chamber is "tight" and random bits of grit or carbon wedge the cases.

I suppose that go/no-go gages are available for chamber dimensions? That might eliminate or pinpoint a potential variable.[/quote]

That was from Ironbear...


Thanks, I have spent the past couple of evenings working on this, HammAR also asked me about the cases I have been using and this is what I have come up with.

Sellor-Belliot cases are the ones that are sticking, I have mixed brass from qualification shoots from the local Law Inforcement range that I use in some of my reloading. This large batch includes Winchester, Federal, Hornady and the S&B. I also have a large bunch of Lake City that I have loaded in the past with no problems. All of the brass, including the "stickers" will fit in the case gauge without hangup, they will also cycle in my H-Bar Colt, only a few of the S&B hang up in the DPMS. I checked those rounds as best I could with an electronic calipers and could see no difference. I then marked the rounds with a magic marker to the shoulder and tried to reseat the round. It appears that the tight spot on the round is below the shoulder. I pulled the bullets on three rounds and put them through the resizing die one more time, reseated a bullet and there was no change. They still would not seat into the chamber. Put them in the colt and , no problem, case gauge no problem. I still can measure no differance,even when I know where to look. I dropped an email to DPMS and I am going to see what they think.

[DeanC]

S&B is not known for being very high quality. Some say that the S&B stands for "Schlecht & Billig" which means "Bad and Cheap" in German.

[selurcspi]

S&B is not known for being very high quality. Some say that the S&B stands for "Schlecht & Billig" which means "Bad and Cheap" in German.

Genau, Das Ist Richtig.

[Seismic Sam]

Well, there's your answer!!! I'd rather share a sleeping bag with Pat Cannon in the Boundary Waters than reload S&B cases!!! Seriously, that stuff is absolute crap.

And that also might indicate something else, depending on whether you are using a FL sizing die or one of the neck sizing dies. If the case is not concentric after being sized (meaning the neck is not on the same axis as the case body to within .001", and if the OAL of your round is long enough, the bullet will be off center when it gets all the way into the chamber, and will bind up. I shoot a .338 Ultramag with 250 grain Sierra Matchkings seated so they are .020" off the lands, and if the runout on the bullet is .005" instead of .001" or .002", I can feel the difference when I'm closing the bolt.

I know tolerances are much looser with an AR than a Remington 700 bolt rifle, but with the S&B crap there could be enough difference in case neck thickness from one side of the case to the other to cause a bullet to be out of line even if it were sized in a FL die.

Seriously, picking up S&B cases is as bad as picking up half smoked cigarettes and cigars from the gutter on Hennepin Avenue and smoking them.

[Vlad]

I have to agree. The only time I had a head seperation was with S and B brass. The only thing it is good for is scrap at a dollar a pound.

[cobb]

You mean to tell me that you think S&B brass is worse than Amerc?

No way.

[gunnerbmg]

Well after todays shooting I have to say I am sure the problem is with the DPMS chamber. It must be tight. The junk S&B brass shoots just fine in my varmit 223 bolt gun. It might be crap but at 16 below laying on cement (army blanket between me and cement) it shoots 3/4 moa. Not as good as neck turned win brass but I guess I was surprised. My reg varmit load was 1/2 moa today. I did not shoot many groups!! BUT, the ammo fits in the case guage, it fits in the H Bar, and it fits in the Rem 700 so, I guess a trip to St Cloud is in the future for the DPMS. Thanks guys for all the ideas...

[DeanC]

You mean to tell me that you think S&B brass is worse than Amerc?

No way.

My 44 spcl Amerc brass has the Starline headstamp.

[Pinnacle]

OK

I just had that happen too.... Bullets fail to go into battery completely with my reloads - guess what - S&B Cases!!!!

My rounds also gauge properly - I am befuddled as well.

[gunnerbmg]

It must be something in the property of the metal, OR...the reloading gods are not finding favor in our efforts ........perhaps we need a super nerd to find the answer!!!!

[Pinnacle]

It must be something in the property of the metal, OR...the reloading gods are not finding favor in our efforts ........perhaps we need a super nerd to find the answer!!!!

Or at least someone that stayed at a holiday inn express last night.

[gunnerbmg]

that might be the only thing that helps!!

[hammAR]

I drove by one last night, but then again I know when to give up on a lost dog..................