Re-barreling an m1 garand

[tiriaq]

Have you established a relationship between how much metal you remove from the barrel shoulder and the change in degrees in hand tight barrel offset? For example, how many thou do you remove to get a barrel that sits at 30 deg offset to change to 15 deg offset?

15 degrees would be 15/360 = 1/24th of a turn. With a 10tpi pitch, 1/24th of a turn would be 1/24 X .100 = .0042.
I generally go a bit shy, then sneak up on it. Better that way than going too far, and turning past index. Torque is also a factor.

 

[Claven2]

Have you established a relationship between how much metal you remove from the barrel shoulder and the change in degrees in hand tight barrel offset? For example, how many thou do you remove to get a barrel that sits at 30 deg offset to change to 15 deg offset?

Frankly, no. I cut off 1 or 2 thou, check hand tight, and if not within 15 degrees, I remove another 1 or 2 thou, repeat. Most I ever had to take was 4 thou on a Criterion. 3 thou on a GI.

 

[Claven2]

More about the action wrench than the other tools. It's easy to twist an M1 receiver.

There are lots of fancy-dancy wrenches out there, I use a home-made copy of the Brownells Mauser 98 wrench, only I reverse the top clamp so that I squeeze the action between 2 parallel flats, snugged down with bolts. Works fine, and I've never damaged an action. Buying a more specialized wrench is fine, but in reality, all of them bear on the bottom legs and the top flat of the receiver up at the front.

I'd post a pic, but I loaned it out to a buddy this week

 

[Claven2]

Installing a previously used barrel is a bit of a crap shoot. Might pull up nicely to index, might not. If it turns past index, rolling the shoulder might get good torque. If the headspace is excessive, there in no fix.

Kunnhausen details how to roll-peen the shoulder to recoup a few degrees of index when installing used barrels. I've never had this issue with an M1, but had to do it once on an M14 back in the days when we could use these at Connaught. Worked fine. Would not be my preferred method though Measure twice, cut once - lol.

 

[purple]

In extremis a large crescent wrench would work on the Garand receiver. As pointed out, the action wrench only bears on the top and bottom of the receiver on a Garand. A length of pipe could be sleeved over the wrench handle to gain additional torque. If you are into re-barrelling more than one type of rifle the Brownells universal action wrench with interchangeable heads for specific receivers would be a good investment. I've been using the purpose made Garand wrench from the US CMP for the past 10 yrs or so; big and sturdy and heavy enough to stun an elephant. Whatever wrench is used make sure that it is a tight fit and that the receiver is protected with card stock or something (a cut to fit piece of breakfast food/coke box works well) to prevent marring the finish.

 

[Claven2]

Whatever wrench is used make sure that it is a tight fit and that the receiver is protected with card stock or something (a cut to fit piece of breakfast food/coke box works well) to prevent marring the finish.

I use business cards