The Firing Line Forums - View Single Post - Mini-Mauser barrel threads?

Harry Bonar · January 17, 2006, 07:20 PM

Dear Shooter:
You should have gotten several gears with your lathe so you could cut the proper thread.
But, all is not lost - Ha! Consult the "feed chart" on your lathe for the amount of advance it would be that would give you 22 TPI, set it for that and you'll probably be O.K.

Now, I take it that it would be 22 TPI with a thread angle or pitch
of 1.5?? Correct, I hope!
Now 22TPI would be a thread (one turn) of .0455 ten-thosands, or rounded off to.046 tip to tip of threads (Hope I'm doing this right!)
So, if you find in your tables a gear setting for .045 it will turn out to be 22TPI. (I think the best I can help you.)
The way to test this is to chuck your removed bbl in your lathe and engage the thread lever with the tool almost touching the bbl. threads and check!
You can grind your tool for the 1.5 pitch to fit your bbl threads and take a test piece of steel turned down to the major dia.' and run a test thread and see if it fits your action!

Hope this helps. If you're getting a Douglas bbl, I'm certainn they'll turn this for you. Harry B.

January 17, 2006, 07:20 PM	#4
Harry Bonar Senior Member Join Date: December 5, 2004 Location: In the Vincent, Ohio general area. Posts: 1,804	mini-mauser threads Dear Shooter: You should have gotten several gears with your lathe so you could cut the proper thread. But, all is not lost - Ha! Consult the "feed chart" on your lathe for the amount of advance it would be that would give you 22 TPI, set it for that and you'll probably be O.K. Now, I take it that it would be 22 TPI with a thread angle or pitch of 1.5?? Correct, I hope! Now 22TPI would be a thread (one turn) of .0455 ten-thosands, or rounded off to.046 tip to tip of threads (Hope I'm doing this right!) So, if you find in your tables a gear setting for .045 it will turn out to be 22TPI. (I think the best I can help you.) The way to test this is to chuck your removed bbl in your lathe and engage the thread lever with the tool almost touching the bbl. threads and check! You can grind your tool for the 1.5 pitch to fit your bbl threads and take a test piece of steel turned down to the major dia.' and run a test thread and see if it fits your action! Hope this helps. If you're getting a Douglas bbl, I'm certainn they'll turn this for you. Harry B.