GM Barrel in 77/22 Receiver

[Covejeepsxj]

I am in the process of putting together a 77/22 with a 17 hm2 barrel. The barrel is a Green Mountain Blued Barrel. The barrel will slide approximately half way into the receiver before it binds up. Green Mountain recommends heating the receiver. I have read about slightly polishing/sanding the barrel to get proper fit.

Any thoughts?

 

[huntsman22]

I had to emery cloth the shank on mine. No big deal......

 

[Covejeepsxj]

Thanks. I am not opposed to doing that, I just didn't want GM to come back and say you altered the barrel if for some reason I still can't get it fit....

 

[Mobuck]

I'd suggest using something to determine where and how much interference is occurring before doing any metal removal.

 

[wwb]

Heating the receiver to fit the barrel is what's called a "shrink fit". there are a couple things you need to know about that:

When you insert the barrel, you need to do it quickly; as soon as the cold barrel contacts the hot receiver, the barrel starts warm and expand while the receiver starts to cool and contract. If it's not done quickly, it may bind up before it's fully seated. The same goes for having it aligned properly as it's inserted.

Second, if it's assembled as a shrink fit, should you ever want to take it apart in the future, it will take an act of God to do so.

 

[Covejeepsxj]

wwb,
That is exactly what I am worried about. I am putting the barrel in a SS 77/22 with a boat paddle stock so the gun has some collector value to it in original form.

 

[5of7]

Just use some 400 grit emery paper cut into strips. It is likely that it will only need to ne reduced by less than 1/1000th of an inch. 8)