muzzel break

IN gunsmith

I am cutting threads on a mosin 7.62x54r for a break 5/8x24 but do not have the break in hand anybody know deep to cut the thread?

IN gunsmith

Hello, I recently bought a used ruger 77/vt in .243 with a screw on adjustable muzzel break. I used several loads with out the muzzel screwed on and it sort of liked a 60 gr infront of 41.5 gr varget. when I used the same load with the muzzel break screwed on, accuary went out of wack. I tried adjsuting it but did not notice any difference in accuary. I heard that a break can acctually increase accuracy, was that a myth or am I doing something wrong? I would appreciate any help on this. Thanks

babun

https://thunderbeastarms.com/tech/thread-specifications

IN gunsmith

thank you

babun

If your barrel is too thin for the min.od, you could uncut deeper then make up a spacer/crush collar to act like a washer for the brake to lock against.

nononsense

IN gunsmith,

I fit probably 15-20 muzzle brakes a week, every week.

With the state of threads on muzzle brakes these days, I wouldn't even attempt to cut threads for a brake until I had the brake in my hand in the shop. Too many manufacturers don't gauge the threads to industry standards so you can flip a coin as to how the brake will fit any particular set of threads.

Even the top-of-the-line suppliers don't gauge properly because they have the brakes made by an outside shop, leaving the gunsmith to final fit every set of threads. I hope yours work out for the best.

Best.

Horse Plains Drifter

I have to agree with NN. Other than that Machinery's Handbook has a formula for depth of thread.

KAMsales

Also, unless the barrel has been cut back a bit shorter, it won't be large enough in diameter for 5/8"x24 thread. Mosin barrels are usually .568" or .585" in diameter and you'd need .625" to do 5/8" thread