So, many years ago I purchased a melonited AAC 260 Remington prefit barrel. Over the next couple years I acquired all the parts to begin assembly. Fast forward to 3 months ago, I had reached about 250 rounds and at 42.3 grains of h4350 I was popping primers and showing pressure sign.
I headed to Rivers bend gun company where Jeff took a look at the bore and said it looked like I had 3000+ rounds down the pipe. The melonite had fractured and as the bullet went through this area it acted like a rasp and peeled copper off the jacket causing excess pressure.
I purchased a stainless Proof Research barrel from a friend (who also helped me machine it). Thank you @noahsmill. The chambering was done with a Clymer reamer from Brownells. All lathe work was done on a 1940s Southbend heavy 10.
I headed to Rivers bend gun company where Jeff took a look at the bore and said it looked like I had 3000+ rounds down the pipe. The melonite had fractured and as the bullet went through this area it acted like a rasp and peeled copper off the jacket causing excess pressure.
I purchased a stainless Proof Research barrel from a friend (who also helped me machine it). Thank you @noahsmill. The chambering was done with a Clymer reamer from Brownells. All lathe work was done on a 1940s Southbend heavy 10.
