Feeding into chamber issues

R

Ritten

Guest
Guys, I've built two .260's now, one on a Stiller action and one on a Surgeon 591 and both are having some feeding issues. Both are repeaters using AICS mags and when pushing the bolt forward the rounds are stripped out of the mags and jam about halfway into the chamber while cocked against the bolt face. Sometimes they jam with the head hitting high and sometimes it's sideways towards the ejection port. When it does this, letting forward pressure off the bolt slightly allows the round to drop in place and to be chambered without a problem. If I run the Surgeon bolt hard and fast it's a non-issue, but with a casual reload it happens about every third or fourth round. I'm also getting crescent moon cuts in the surface of the brass that looks like the round is being shaved against the chamber entrance. After chambering the barrels I cut a very slight 45 degree about .020" deep to get the edge off of the chamber wall. Could this still be to sharp a corner for the chamber walls? Any thoughts or similar problems? It happens the same with six different magazines.
 
Also make sure the ejector is not proud of the bolt nose, the back of the case will catch on it and cause the the cartridge to hang up at the chamber entrance.
Gary Eliseo
 
Just fixed one of these the other day, had to take off the barrel and put a radius on the mouth of the chamber. It was catching the brass at the case mouth when single loading off a Stony Point magazine adapter.
 
Like Mr. Eliseo said, Check the ejector. Take it out and cycle a few?

Kyle
 
Also make sure the ejector is not proud of the bolt nose, the back of the case will catch on it and cause the the cartridge to hang up at the chamber entrance.
Gary Eliseo


Mr. Gary, you hit the nail on the head. I had pulled the barrel to polish the chamber edge a bit and when that didn't solve the problem I remembered your suggestion. The ejector was proud .050-.010" so I took off .025", put a slight 45* chamfer on it, polished it down with some 320 and it now runs as smooth whether it's cycled fast, slow, hard or pansy. Thank you sir!
 
Something I do to all AICS/ single stack mags is open up the feed lips on the front. Not much but just enough to give the round a more nose up posture. I've seen this many times as the bullet clears the mag and starts up the feed ramp in the action the cartridge pivots on the lips and the case head drops below the bolt nose. Even if it's not causing that problem it feed much easier with a nose up position.

Dave
 
Thanks Al cool site- Widgetsupply. If anyone wants to work on their bow-should check out the bow tools. Some things are not quite what you would think. Interesting looking containers.
 
Thanks Al cool site- Widgetsupply. If anyone wants to work on their bow-should check out the bow tools. Some things are not quite what you would think. Interesting looking containers.

Not quite the bow tools I was expecting.
 
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