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akjunkie
07-12-2009, 7:45 PM
Went to the range today, had a Collapsible stock lower mated with a 20in upper.

Was experiencing feeding issues.

Trying to narrow the problem down to the CProduct 10rd mag or using a Carbine Spring with a 20in gas system.

Weapon will shoot, eject round, close bolt, chamber Empty.

After each shot I would have to manually pull on the charging handle to load a round in the chamber.

comments?

Josh3239
07-12-2009, 7:50 PM
The gas system has nothing to do with the buffer assembly. Definetly try mags first. What ammo and buffer are you using?

Tony.
07-12-2009, 8:41 PM
Probably the ammo. Try using some Federal XM193.

Magnanimous
07-12-2009, 8:55 PM
Is this a new setup? Has the rifle worked properly before? What has changed?

My 20 inch was short stroking after changing out the front post for a gas block. After taking a look the gas block was canted a few degrees. Loosened the set screw adjusted and was back in business.

With a bit more information you will get your answer. Until then the answers given will be guesses.

akjunkie
07-12-2009, 9:12 PM
shot several thousand rounds thru my DPMS 20in upper before, mated to my pre-ban Bushmaster A2 lower.

Recently finished building an OLL / Carbine lower.
Wanted to test fire my new OLL.

Was using Winchester Q3131A, 55gr.
Used regular buffer spring and tube.

Next trip i'll try to use another 10rd mag.

For sure it's not my DPMS upper.

Hmm, also got a Pre-Ban Bushmaster M4 Lower. I should mate that to the DPMS 20in and see if it got any problems with that combination.

Magnanimous
07-12-2009, 9:26 PM
From your description, I guess it could be a bad mag.

Shooting a rifle length upper on a carbine lower should work. I've done it.

A buddy loaned me a mag that worked great in his setup. It would mis feed every round on my set up. Sometimes rifles just don't like certain mags.

Josh3239
07-12-2009, 9:33 PM
By "normal" does that mean the extention, spring, and buffer are all carbine style?

akjunkie
07-12-2009, 9:45 PM
By "normal" does that mean the extention, spring, and buffer are all carbine style?

YES.

Josh3239
07-12-2009, 10:03 PM
Just checking, you'd be surpised how confused people get ;)

akjunkie
07-12-2009, 10:11 PM
Yeh, I suspect it's a mag issue.

Funny thing is, I had 2 more 10rd Cproduct mags at home.
Should've brought them with me. But I was lugging 6 rifles with me today to Range.

aplinker
07-12-2009, 11:59 PM
Yeh, I suspect it's a mag issue.

Funny thing is, I had 2 more 10rd Cproduct mags at home.
Should've brought them with me. But I was lugging 6 rifles with me today to Range.

The test for short stroking is to see if the bolt will lock back on the last round, so load just 1 round.

What buffer are you running? (if you don't know, where did you buy it?)