Specialty Pistols
XP caliber differences

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February 16, 2020, 03:35 PM
XP caliber differences
I have an XP that is giving me a bit of feeding trouble. It has an aftermarket barrel chambered in 7x47 helm, which is like a 7tcu that uses 222 magnum brass. The problem is that it doesn't feed worth a hoot. The bullet nose will jam into the barrel below the chamber opening. If I use a second hand while closing the bolt and push down on the head of the case, the bullet can just barely make it into the chamber. No flat point bullet will work. Someone has deepened the feeding trough in the middle to try to make a bit of a dip for the case head to sit in as the bolt closes, which would help the bullet tip sit higher. At first I thought it was a barrel problem and needed a bit of a radius added to the chamber. There is a tiny radius but I don't think adding a bit more would help. So that leaves me with rebarriling to a larger diameter case. I tried a 22-250 and the bullet still hits due to the case taper. Im thinking 22-250 ai would work but don't have any to try. Now I am wondering if that though is all wrong and maybe should be welded up. It looks like a bolt face enlargement is going to be in order as I can't think of any 223 head size that would work. Just looking for suggestions and thoughts really.

February 16, 2020, 04:23 PM
They just didnt put enough chamfer on the chamber mouth.

The little cases like 223, 222, 221 are more prone to this issue