.308 in DPMS AR's

[CaptG]

Is anyone else out there shooting a .308 DPMS AR who has any comments/suggestions on ammo? Mine has had no problem with anything with a NATO headstamp, and also works well w/ Indian surplus (OFV 75). I have tried 147gr Privi Partizan and about 2/3thirds of it won't chamber. I know that DPMS warns against Israeli, Korean, PMP and South African. Does anyone out there have any experience with this ammo in this rifle?

Thanks all
CaptG

[fepowered]

DPMS is following the trend of CYA when it comes to ammo recommendations.  They do not wish to be liable for a customer's  kaboom or warranty work because of ammo...   My recommendation is to find what your rifle likes and stick to it...   I am really suprised that it does not like Prvi Partisan as it feeds and shoots better than any of the surplus I have tried in my Armalites and M14 (when I had it).  Take a stroll over to ar15.com and ask about DPMS feeding with the different ammo...  You are likely to get ALOT of feedback.....

[funfaler]

I have seen 2 different DPMS 308 models that would not eject South African, Port, CAVIM, or Argentine

YMMV, good luck.

[KodyJaret]

PRIVI runs slick in my SA58 (everything I've tried does for that matter.)
Failure to chamber is odd as as PRIVI  is commercial grade ammo. I'd contact DPMS for a start.

As for failure to eject, I'd explore one of these :

http://jtdistributing.net/store/barrels_gas_blocks.html

[CaptG]

Thanks for the replys. So far no ejection problems, only feeding/chambering.
CaptG

[ashrn03]

A friend of mine had a chambering problem with a brand new DPMS 5.56.  It appeared the throat hadn't been cut properly (if it had been cut at all).  Bullets would be engraved with rifling when chambered.  Manually extracting a loaded round was difficult, requiring a mallet to rap the charging handle back.  In one case, the bullet stayed in the chamber when the case was extracted, spilling powder all over the action.  It went back to be checked under warrenty.  If you have a bullet comparator you can check the relative length of a 'good' round versus a 'problem' round and see if the ogive is closer to the nose on the 'problem' round.   

[CaptG]

Thanks ashrn03,
Would checking with a go/no go guage diagnose this? I think a friend of mine has them.
GaptG

[SamD]

 A Go/No wouldn't do it as they check for overall length as opposed to positioning of the ogive of the bullet.
Part of the difference in spec between 308/7.62NATO/other 7.62.  The throat is specified for a 150 FB FMJ if they radios of the bullets you use is farther forward than that, it may not chamber fully.

Take a loaded round of the "bad" ammo and color it with a magic marker from head to toe. Load it in a mag and charge it, then extract manually and see where it interferes (where the marker is rubbed off). That will tell a lot about what the problem is.

Post a pic then we can make intelligent guesses.

Sam

[CaptG]

Tried the magic marker. My camera's dead so I'll try to describe what I see. Some spiral marks were made on ogive of bullet, but I also see them on a Win. USA round that feeds fine. There is a very faint line all around the brass just above where the shoulder starts. Eyeballing the Win and Privi side by side, it looks like the angle of taper on the Win is sharper than the Privi and the neck on the win starts lower (with both cases standing up). Again, just eyeballing it, it looks like the case is causing the problem.

On my way to AS at Davilla in a while, but will post pics next week.

Thanks for the help

Guy

[SamD]

from teh description of the "ring" Sounds like a slight "crimp collapse" on the privi.
I'll wait for the pix to confirm but it sounds right.
AR have a weak closure so you'd be hard pressed to force it closed in a pinch.

[Pappy]

Hello Group; Does the rifle or rifles in question have a MATCH chamber or some other wilde idea of standard. Small base dies and cases trimed to there minimum after sizing could cure the or a tight chamber. Just a thought, Pappy

[KodyJaret]

Another thought,,,PRIVI is generaly considered pretty good stuff,,,


   ,,,but check the dimensions of those catridges. This from another site, the poster is a very expierienced ammo tech & competitor. > :

"Yesterday afternoon I decided to rebarrel my 1911 Swiss carbine as I had just got a new 7.5 Swiss reamer from PTG and a GO Gage. I threaded it all up and was chambering it. Was getting right down to the last couple of thou for the GO and something told me to get some of the PRVI brass and check it.
WOW, it was like .008" under a GO gage ! ! ! I figured this is not going to help brass life to have it stretch .008" just to get up to GO dimension so I bumped the shoulder up and headspaced much tighter on five cases which varied a little.
I like the brass, it is stress relieved leaving the color on which I like to see and I read the primer pockets are nice and tight. Looking forward to loading it in the Swiss rifle. Tomorrow I guess I will mount a scout scope on it and rebed the first inch of the barrel channel and free float the rest.

Oh yeah the flash holes are all nicely centered."

[Redwolf]

CaptG, I have a DPMS 308 24 SS. and it dose have a very close chamber. I have not had any problems using Mil sup or Privi and I have shot plenty of PMP. Once in awhile I do have an unfired round stick in the chamber that you cannot un-chamber with the charging handle alone. I have to give the bolt a start with the nose of my multi tool to get the round out.
I have found that if I shoot any round in my FAL, (that includes Win, PMP or others), and reload them in standard RCBS dies the round will not chamber in the DPMS. It will not even let the bolt come close to closing. You will be left prying the bolt open because it will wedge tight.  However, if I reload them in RCBS small base dies the same brass runs through the DPMS just find. The chamber is tight to specs and some ammo manufacture loose to specs.
  I have run through 600 + rounds and it is smoothing out nicely. This thing is a tac drive at 400yd +. I would like to find a range were I could go out to 700yd or 800yd to see what it can do. Any way I hope the info helps.

[CaptG]

All those who've helped me on this, thanks! LabRat checked a few of the rounds for me and they're on the large end of 7.62 tolerance. I've got a .308 chamber that's probably on the tight side. Haven't decided whether to re-chamber or just sell the rounds and stick to stuff I know works. It's all expensive now anyway.
Thanks again
G.