17 HM2 case ruptures
 

I have a converted 10/22 (New E. Authur Brown Barrel, and bolt handle) I took it to the range today and it ruptured the cases after about 20 or 30 rounds. Ran a cleaning rod with a brush on it the second time it did it, The third time it blew the magazine apart. I was using Hornady ammo. Had the rifle checked by a gunsmith he said everything appeared okay. Hornady wants to look at the cases, they blew at the rim or right by it. I havent been able to reach EA brown yet. Has anyone had this problem yet. the gun has had about 150 rounds through it all together

Welcome to HuntChat.

When you say the gun was converted, was the bolt and spring changed out, or just a barrel swap?

A proper conversion MUST have a new bolt and recoil spring, both much heavier than the original. The .17HM2 creates MUCH higher bolt thrust than a standard .22LR and if the bolt opens too fast, the inevitable result is a case rupture, exactly as you describe.

As they say in Texas, "Ever Tahm."

The conversion was a new spring and heavier handle to add the extra weight to the bolt.