Modern Sporting Rifle Evolution
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FeralCatz

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Reply with quote  #1 
So I finally got around to using the 2nd barrel I had and built an almost identical gun to my first mongoose. 20" 4groove 8 twist barrel, side charging, first build performed amazingly, with this one I've had every case come out damaged. Just chambering scrapes 1/4 around the case and pushes it in. It's got me concerned to use the gun, I checked the feed ramps, the chamber seems sharper on the bottom edge, more so then my other mongoose, but my first one has 1500+ rounds through it so I can't be sure it wasn't like that from the start.
My question is, what would cause the cartridges to get damaged in this way?

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RedRaider

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Reply with quote  #2 
Questions:
What type of firearm, hand feeding or bolt feeding rounds, AOL, tried different mags (if mag feed)? Need more information.
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BIGGDAWG

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Reply with quote  #3 
give the chamber a little polishing and shoot a 100 or so rounds through it to break it in and see what it is doing.

new chamber it can be getting that from the breech as it goes in the chamber if there is a slight edge on it. some flits on a chamber mop and a drill and a minute of your time should take care of that.

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FeralCatz

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Reply with quote  #4 
Quote:
Originally Posted by RedRaider
Questions:
What type of firearm, hand feeding or bolt feeding rounds, AOL, tried different mags (if mag feed)? Need more information.


It's an AR-15, that specific cartridge's oal is 2.305, I've used asc as magazines, pri 5.56 and pmags. All produce the same issue.
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