Problem chambering rounds with GM bull barrel.

Allstone

Allstone

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Noticed that the chamber gets really really tight around the base of the case of the cartridge, so much so that it sometimes feels really tight as I try to eject it. Noticed that the cases are just snug on my factory chambers, that the round doesn't wiggle and is able to still freely fall in and out of the chamber. This is my first "target grade" barrel...does this super tight fit seem typical of this kind of barrel, or is mine possibly out of spec?

The rounds get hung up on the bottom lip of the breech, and gouges the nose of the bullet on the bottom. Doesn't seem to matter if I use the factory v-block, or the VQ adjustable modified v-block with the set screw...I've fiddled with both and the same problem persists.

This is a 20" Green Mountain plain blued bull barrel that is brand new. The ammo I was using was CCI Standard Velocity in LRN and LHP. Interestingly enough, I didn't have any problems with the first magazine...but every other magazine after that was a problem. Too bad really...as it now shoots 0.5" groups at 50 yards using cheap ammo.

Time to take it to a gunsmith? Thanks for any tips.
 
chamfer

What I do on most barrels is create a small chamfer on the bottom of the chamber opening. I use a small tapered stone from a dremel kit and just turn it by hand to create a small chamfer where the bullet enters. I then use very fine sandpaper to polish the same area. It seems to work for me, as more often than not, I can shoot Experts without issue. Just polish the mouth of the chamber and your issues will most likely go away. Good luck, Later.
 
Thanks for the tip, 10mark22...but in my frustration I managed to find the cause of the problem and the solution. The biggest problem was the ammo itself...I noticed that the profiles of the lead round nose and the lead hollow point are very different. The hollow point has a much bulkier bullet, and I suspect it doesn't fit the tight match chamber. I don't know if anyone can confirm this or not...but I tried the round nose and it now chambers easily and releases easily.

I also aligned the cutout to the extractor much better, and torqued the bolts better...and now it extracts better also. Looks like the extractor sits mutch more flush than before.

I'm glad it's fixed because it was starting to bug me how much I just spent on this rifle to not have it work. :D

:cheers:
 
There is a warning on the side of GM barrels that they may not eject live rounds due to the match chambers.
However, I only run round nose through my GM barrels, I find hollow lead even hangs up on my bolt guns.
Never shoot Stingers through it....or you could be in for a surprise.:)
 
I did notice that warning on the side, Hitzy...in my case, there should also have been a warning that it won't chamber some rounds. :D In any case, it's my first experience with a match chamber, and I'm fairly new to guns also...so there's a bit of a learning curve on my part. Thanks the tip...I'll stay away from Stingers. I've heard they're a touch long even for some regular chambers.
 
pitdogboy said:
CCI standard velocity ammo seems to work great in my match barrels
Click to expand...

Yeah, it did on mine too. I figured out that the first magazine had those loaded in it as I had a few left over, and it was the only magazine that worked. The others were all loaded with CCI Subsonic HP, which had the bulky bullet profile that didn't want to load in my match chamber. It has the big squared off shoulders, and I suspect this was jamming up right against the rifling.

Has anyone ever tried the Gold Medal Target ammo made by Federal? Any good? The price is right. Can't seem to find any Eley's locally right now.
 
Is this problem with the ruger mag or aftermarket or both?
I had a gm heavy barrel that would feed great with the ruger rotary mag but would jam using the eagle mags I had.
 
super7 said:
Is this problem with the ruger mag or aftermarket or both?
I had a gm heavy barrel that would feed great with the ruger rotary mag but would jam using the eagle mags I had.
Click to expand...

Nope...the problem was related to the hollow point CCI subsonic ammo, not magazine related at all. The actual HP bullet had a bulky profile and shoulder that jammed up in my chamber. The RN fit just fine. No problems with any magazine as long as it's a RN.
 
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