Thread size...

[long40shot]

My hunting rifle is a 300wm on a #3 Bartlein. I think it's .670 diameter at the muzzle. What thread pitch is needed for a muzzle break?

Matt

 

[tac284]

I try and shoot for .05 to .06 a side for shoulder contact. Doesn't always happen..... in your case (.670) if you go with .625 (5/8) you will have .022 per side for your shoulder and it leaves the most material around your bore which is great. If you go .562 you get .054 shoulder but with thread depth included you have less then .125 of barrel wall per side. Will you be removing the break?

 

[carlsbad]

Go big. --Jerry

 

[long40shot]

9/16" ?

 

[carlsbad]

I'd put the 5/8" on. No chamfer on the MB shoulder to maximize contact with barrel shoulder. Nice tight thread fit. This is not a load bearing joint, just needs to stay in place. --Jerry

 

[tac284]

I'd put the 5/8" on. No chamfer on the MB shoulder to maximize contact with barrel shoulder. Nice tight thread fit. This is not a load bearing joint, just needs to stay in place. --Jerry

Yes, this would be my exact thoughts.