I want to thread a 300 WSM for a suppressor. Problem is the muzzle diameter is .584" and most places require at least .600" for a 1/2-28 thread (some want more). Would I need to cut it back until I have more metal to play with?
Oh, and the barrel is 23" from the factory. I have reached out to LRI, so I will see what they say but just curious to hear any other ideas. Perhaps the answer is to just leave it alone.
Thanks
The minor diameter for a 1/2-28 thread is about 0.46". If you thread it 1/2-28, with a .275" bore, you will have an effective wall thickness of .092”
I did a quick n dirty hoop stress analysis for a thin wall vessel, for 4140 barrel steel @ .092 wall thickness and came up with 30,000 psi being your max allowable pressure at the muzzle, with no safety margin. At 30,000 psi, the muzzle wall will be at 90,000 psi in tension, which is the yield point for 4140 steel.
Your bore pressure when the bullet is at the muzzle is likely about 10,000psi, but that is a wild ass guess.
You could cut the barrel back to a point where the diameter is .6" and it would probably work, but you may end up with a pretty short barrel, which would sacrifice alot of velocity for that cartridge. You'd still have a thin effective wall thickness at the muzzle.
I personally wouldn't do it. I would either rebarrel to something heavier, or get a different gun for suppressing.
