Gun Hub Forums banner

1 - 7 of 7 Posts

·
Registered
Joined
·
807 Posts
Discussion Starter #1
If one needs to clean up the muzzle on a Garand, how much can one take off before it starts to affect the gas pressure and reliability?
 

·
Registered
Joined
·
361 Posts
I think it was Brownell's that sold a crown dressing bit or do you need to counter bore?
I have used the crown dressing bit/tool and got good results but never counter bored.
 

·
Registered
Joined
·
807 Posts
Discussion Starter #3
A barrel with a muzzle defect that needs cleaning up. I think I can take off about .100" and it will clean up.
 

·
Registered
Joined
·
2,424 Posts
I have taken .100 off the length of M1 barrels and they worked fine. They get a little snub nosed look to them, but functioning seems uneffected. If the rifle cycled before, it should cycle after.

:thumbsup:
 

·
Registered
Joined
·
352 Posts
This counter-bore is 3/16" deep and the rifle functions perfectly. I've heard that you can c-b back to just in front of the gas hole and the rifle will still function but I never have received a definitive answer as to how far EXACTLY a bore can be c-b'ed before the function gets violated.
Jon
 

·
Registered
Joined
·
5,714 Posts
Jon, the problem with counterboring is that you can only counterbore once or twice before you have too much and it affects accuracy. As for cutting back, I cut one back almost 3/16ths of an inch without affecting operation. you do have to trim back the muzzle-tab on the locknut though. Refaced and crowned it, took it from a 4 to a 1.
 

·
Registered
Joined
·
1,186 Posts
One of the best purchases I have made lately is the CMP muzzle gage that looks like a 308 round with long bullet. It will tell you exactly how much muzzle wear there is and will give you an idea of just how deep you need to go to get good rifling.
 
1 - 7 of 7 Posts
Top