Barrel Threading

[bigngreen]

You may want to check this out and look at some of your barrels that are currently threaded for 1/2x24 or 5/8x24?

It's all about the guy threading or how aggressive the program, I've cut many brake tenon's off and re-threaded, you can't do it like you charging $50 to do it, you have to take appropriate care to not open up the bore.

 

[Ucsdryder]

Call TBAC on Tuesday. They're incredibly helpful.

 

[JuddL]

The US gun industry really needs a shake up in term of the thread options it offers to its consumers.
Most European suppressor manufacturers are able to offer their products in the following threads:
1/2-20,1/2-28,13x1,14x1, 9/16-24,15x1, 5/8-24 ,16x1, 17x1, 18x1 , 18x1.5 ,3/8-24...etc
A cnc machine can cut any thread you want, metric or imperial at the change of a threading insert on the tool holder.

Most manual lathe can cut both metric or imperial.
But just for the sake of keeping things simple, an intermediate thread size like 9/16-24 makes complete sense.

The archery industry has managed to organise and standardise its range of threads , the gun industry should be able to do the same.

I think it has…take that list and drop all the communist (metric) threads and that's it.

90+% of the bigger than 22 cal cans are 5/8-24 and most of the 22 cal cans are 1/2-28. That's a pretty decent standard.

 

[milestown]

It's all about the guy threading or how aggressive the program, I've cut many brake tenon's off and re-threaded, you can't do it like you charging $50 to do it, you have to take appropriate care to not open up the bore.

How do you recommend to thread a barrel to keep the bore from opening up?

Hal

 

[bengineer]

How do you recommend to thread a barrel to keep the bore from opening up?

Hal

Leave as much diameter as possible.

 

[qotsarock]

1/2-28 should be fine

 

[davidheart]

How do you recommend to thread a barrel to keep the bore from opening up?

Hal

Take multiple 2 thou passes so you're not over working the steel and only take as much as you need. Fit should have clearance but not be loose.

Threading 1/2x28 on a 30 cal is generally not recommended, but I haven't experienced any issue with my 30's on featherweight barrels. Do take note your zero will move substantially with a suppressor on a featherweight barrel. Always confirm zero before hunting!

Make sure your smith takes his time,

• First prepare the 1/2x28-5/8x24 adapter by indicating on shoulder side of the adapter. Face the back side so it'll be square for later use.
• Dial indicate off the bore of the barrel instead of the outer diameter or deltronic pins
• Face the muzzle.
• Turn down to 0.500 diameter slightly longer than the thread adapter length
• Reindicate to verify zero hasn't moved,
• Turn down to 0.498, set your undercut at .457 and face your shoulder
• Thread to 1/2x28, checking your work, taking only enough to tightly fit a 1/2x28 to 5/8x24 thread adapter.
• The adapter and the shoulder should be perfect. Red loc-tite and clean.
• Face the muzzle and crown.
• Face the shoulder of the adapter so it's 0.600 from the muzzle.
• Clean up the backside of the muzzle so it blends at an angle with the barrel.
• Finish to your preference and enjoy.

I have this on my Tikka, Model 7, and CZ527. The Tikka barrel being the thickest of the bunch and all shoot beautifully using suppressors. I *think* I have the right steps laid out above but a good smith should be able to remember anything else important of note.

 

[milestown]

Dave

Thanks for the reply.

Hal

 

[davidheart]

No worries Hal! Hope it was helpful in some way. It's very possible to thread a featherweight 30cal. The smith just has to be very cautious when doing so.

Somebody previously mentioned threading at 60rpm. That's a very strong person! I tried doing that yesterday and almost fell asleep on the first pass. I thread at 174rpm and use Viper Venom cutting fluid. The shop owner threads at ~180 I believe and our CNC machine is faster yet. The threads look clean enough for high end F-Class rifles.

- Joshua

 

[coast2coast]

Call TBAC on Tuesday. They're incredibly helpful.

Agreed. TBAC can cut and thread the barrel for you. And time and install the muzzle brake.

 

[Dave in WI]

Somebody previously mentioned threading at 60rpm. That's a very strong person! I tried doing that yesterday and almost fell asleep on the first pass. I thread at 174rpm and use Viper Venom cutting fluid. The shop owner threads at ~180 I believe and our CNC machine is faster yet.

I thread at 70 RPM and it still scares me....

 

[davidheart]

Haha! Maybe we're just impatient.