Thread: Model 60 tube mod.

Originally Posted by Growlybear

I'd do it in a heartbeat.

For a semi, it is a difficult thing to do. The lifter needs to be able to cope with the longer shells, then there is a need for a heavier bolt as just putting in a heavier spring is not sufficient. How does one make the bolt heavier?

A web page giving an idea of the formula for bolt weight required: https://orions-hammer.com/blowback/ but I get a figure of twice as heavy a bolt being required (0.82lbs for .22WMR vs 0.4lbs for .22LR) for similar initial bolt movement rearwards. Not to be compromised on as it is a higher pressure cartridge, the poor way of doing it is with heavier return springs but that is hard work on the gun's innards.

But alas, ten rounds of .22WMR is ... ten rounds of .22 WMR. A better outcome than what you had before... if it IS possible, that is.