Thought i could see marks on the bottom and slightly up the right side of the bore, as if the bore was contacting the breech face heavily in those areas.
Funny you should say that.
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Shortly after I got into the Handi game I had a friends .308 that just would not shoot consistently. I put a good 200 rounds through it trying different handloads to no avail.
The I was directed (by MSP ret
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) to GBO. With Tim's patient guidance I found that the barrel face had high spots on the right side of the face that were being peened down each time the rifle was fired. In effect the barrel was banging side to side against the receiver face!
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I guess where it came to rest between shots dictated where the bullet would land.
This action had gotten so severe that one side of the spacer was also peened down.
So I trued up the face of the barrel, shimmed the action and now the rifle shoots almost as well as my friend's Browning bolt gun!
Now I check how true the barrel face is on ever Handi I get!
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Some may need to be trued, most don't. It's just become part of my "hand fitting" process.