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tgun
04-27-2008, 3:02 PM
Was this caused by using Wolf?

On my second trip to the range with a new upper, about 50 rounds into shooting, the case gets stuck and the primer falls out into the mag. The case was stuck so hard that I bent a cleaning rod trying to get it out. There was a lot of sand and wind blowing around. What went wrong? I shot about 150 rounds of Wolf through the upper on a previous trip and then cleaned it. Maybe I suck at cleaning.

http://i203.photobucket.com/albums/aa119/travoc/stuck-0029.jpg

Bobula
04-27-2008, 3:13 PM
Wolf

hawk1
04-27-2008, 3:19 PM
Over charged round?

buffybuster
04-27-2008, 3:32 PM
A few questions:
Exactly what kind of upper configuration is this (AR-15-20", M4-16", Mid-Length-16", etc..)?

Do you know if the gas port is the standard size?

Do you have the blown out primer?

Did the extractor slip off the cartridge rim? Can't see any extractor marks on the rim from the pictures.

Have you shot this upper with other ammo (brass cased)?

Are you using a Carbine Buffer?

Does your barrel have a chromed chamber/bore?

Just off the top, from the pictures, I would guess that the BCG is moving back and unlocking while there is still gas pressure in the case which is gripping the chamber walls. That would account for the blown out primer.

If the chamber was dirty, the case would get stuck but the primer wouldn't be blown out.

Since the steel cases aren't as springy as brass cases, the timing of the firing cycle is more critical. If the barrel has some rounds thru it, the edge of the gas port could be beginning to round or if new, the gas port might be too large. Either way, there's too much gas pressure coming back to the BCG.

Any more details?

bohoki
04-27-2008, 3:45 PM
i bet it is a 16" barrel

probably a weak extractor spring combined with the headspace

get the gages

aplinker
04-27-2008, 3:59 PM
Maybe I suck at cleaning.



Wolf is dirtier and causes a thick build-up. It becomes like paste if you leave it in place and don't clean it out. Happened to me a couple times until I realized just how aggressively I needed to clean the chamber.

I would start with that and work from there. REALLY use solvent and a brass brush.

buffybuster
04-27-2008, 4:32 PM
Wolf is dirtier and causes a thick build-up. It becomes like paste if you leave it in place and don't clean it out. Happened to me a couple times until I realized just how aggressively I needed to clean the chamber.

I would start with that and work from there. REALLY use solvent and a brass brush.

Wonder if he was using the old lacquer coated Wolf or the newer poly coated. The lacquer coated can get nasty but the poly coated has been pretty clean in the chamber.

buffybuster
04-27-2008, 4:35 PM
I was looking at the picture again. Is that rust on the right feed ramp? If the chamber isn't chromed and it's slightly rusted, that would stick the case.

aplinker
04-27-2008, 4:40 PM
I was looking at the picture again. Is that rust on the right feed ramp? If the chamber isn't chromed and it's slightly rusted, that would stick the case.

The new Wolf still builds up fouling in the chamber.

It looks like copper/brass on the feed ramp.

USN CHIEF
04-27-2008, 4:45 PM
I had the same problem yesterday at the range yesterday. It happened twice with Wolf ammo. Problem, rifle was dirty, ran a swab once throgh it and I had no more problems... It was my fault. Last week I went to the range and shot about 300 rounds of wolf and I was too lazy to clean my AR...

tgun
04-27-2008, 5:06 PM
CMMG 14.7 Lightweight CAR Upper w/Permanent Hider (A3, Semi-Auto Carrier, E.G.R.E.S.S Bolt Upgrade, No Charging Handle Upgrade, Extended/Polished Ramps, A2 Post, F Marked Front Sight Base, Round Forward Assist, M4 Handguard-Single Heat Shield, No Rear Sight, A2 Hider)

Primer pictured below. I don't think the cartridge photo is going to help you since I tried to pry it out with pliers.

This upper went through 40 rounds of Federal XM193 on the previous outing, nothing but Wolf since then.

I think it is a carbine buffer - it came with the Magpul CTR Stock combo.

All CMMG lightweight uppers are supposed to have chrome-lined bore and chamber.

http://i203.photobucket.com/albums/aa119/travoc/IMG_3146.jpg
http://i203.photobucket.com/albums/aa119/travoc/IMG_3145.jpg

A few questions:
Exactly what kind of upper configuration is this (AR-15-20", M4-16", Mid-Length-16", etc..)?

Do you know if the gas port is the standard size?

Do you have the blown out primer?

Did the extractor slip off the cartridge rim? Can't see any extractor marks on the rim from the pictures.

Have you shot this upper with other ammo (brass cased)?

Are you using a Carbine Buffer?

Does your barrel have a chromed chamber/bore?

Just off the top, from the pictures, I would guess that the BCG is moving back and unlocking while there is still gas pressure in the case which is gripping the chamber walls. That would account for the blown out primer.

If the chamber was dirty, the case would get stuck but the primer wouldn't be blown out.

Since the steel cases aren't as springy as brass cases, the timing of the firing cycle is more critical. If the barrel has some rounds thru it, the edge of the gas port could be beginning to round or if new, the gas port might be too large. Either way, there's too much gas pressure coming back to the BCG.

Any more details?

tgun
04-27-2008, 5:12 PM
And the Wolf ammo that I was using comes in a black box with a little bit of red around the primer. Not sure if that's the lacquer-coated version or not.

That might be rust on the feed ramps, although I don't remember seeing it before I shot.

The only think I have cleaned it with is a can of Breakfree CLP. I guess I need to get some solvent.

tgun
04-27-2008, 5:16 PM
I tried to enhance a photo of the lip before I went crazy with the pliers.

http://i203.photobucket.com/albums/aa119/travoc/stuck-0027.jpg

1lostinspace
04-27-2008, 5:59 PM
That is not due to a dirty chamber it is also a classic sign of over pressure or loose primers.
With Wolf I don't think you would run into over pressure

buffybuster
04-27-2008, 6:50 PM
I would clean the chamber real good and keep shooting.

That 14.7" barrel, has essentially an M4 gas system which has higher gas port pressure than the original AR15/M16 design and as a result the timing of the BCG is more critical. It's an original design issue. You could try a heavier bolt carrier. OR stay away from steel case ammo.

aplinker
04-28-2008, 2:29 AM
The issue is the FTE, not the primer, IMHO. You just need a good chamber brushing and maybe some solvent.

That is not due to a dirty chamber it is also a classic sign of over pressure or loose primers.
With Wolf I don't think you would run into over pressure

It's one round that had a FTE. It's not happening a bunch.

I think the primer coming out is a consequence, not the cause.

motorhead
04-28-2008, 7:53 AM
check case for swelling. check other brass for bulged primers. CAUTION- these 2 items are classic symtoms of excessive headspace. the primer in pix doesn't look blown out but if it was mine i would check before pulling the trigger again.