Muzzle Threading — Don’t Remove Too Much Steel

[rudysts]

I saw this article and video on this subject I found it interesting. anyone else have knowledge on this.

http://bulletin.accurateshooter.com/2015/04/muzzle-threading-dont-remove-too-much-steel/

 

[carlsbad]

I'm a mechanical engineer and I would have bet against this result. However, it isn't "impossible" in my opinion. It all depends on the residual stresses in the barrel, especially radial stresses. I've seen it said, and perhaps others will validate, that turning a barrel down from bull to sporter or similar will cause the bore to open up perhaps .001".

In general I like to take as little metal off a barrel as possible whenever I work on it. So I am in favor of the suggestion of using a larger thread diameter and I usually do if I'm doing it for myself.

--Jerry

 

[Minesweeper3433]

A teacher I had proved it to me with a krieger barrel we had in the lathe. He made a slug for the barrel and had me slug it when it had a crown on it then we threaded it to 1/2-28 from a bull and made me slug it again. At the very least it loosens the bore up enough to physically feel it.

 

[akajun]

This effect can also be mitigated by taking small cuts, use of coolant or cutting oils when flood coolant is not possible , and sharp tools.

 

[Joe Salt]

Checked both my L.G.'s I have gage pins, and they went right past the cutting point. Could it be how fast the treads are cut? Heat sure can be a factor.

Joe Salt

 

[rudysts]

I recently had a brake put on one of my rifles and it totally lost its accuracy even with out the brake it doesn't shoot. it wasn't threaded with 5/8 x 24 it is smaller probably 9/16 so now I am wondering if this is the cause. I don't have gauge pins to check if it has the bell effect.