Author Topic: Machining a breechplug tang  (Read 7445 times)

Offline Acer Saccharum

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    • Thomas  A Curran
Machining a breechplug tang
« on: August 12, 2012, 06:01:32 AM »
I know this really is helpful only to those who have a bandsaw and milling machine. But maybe the fixture idea is useful in other ways.

This is a simple fixture, a flat sturdy plate with a threaded shaft collar screwed to it. Yes, it's an off-the-shelf item, available in many thread configurations, both National Coarse and Fine, from McMaster-Carr or MSC. I like the two-piece split collar better than the one piece style collar illustrated, because it accommodates variations in plug size better.



Screw the already threaded plug into the fixture. Clamp in saw, tilted to get the angle you need for the flare of the tang. In this pic, the sides have already been slabbed off, and the underside of the tang is being cut.



Flip the plate vertical in the saw, and make a cut to meet the first cut.


With this style fixture, the part can be rotated to match the angle of the blade. The saw is only parallel to the base when the saw is all the way down, so rotate the part accordingly.


Tang is only sawed at this point. Now take it to the mill.


Mill all sides, rotating part in fixture as needed. Because the part is so extended, take light cuts only.

« Last Edit: February 26, 2013, 09:35:49 PM by rich pierce »
Tom Curran's web site : http://tcurran.com/

Offline D. Taylor Sapergia

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Re: Machining a breechplug tang
« Reply #1 on: August 12, 2012, 06:40:56 AM »
I added a new .62 Smooth bored barrel to a rifle that has a .62 cal rifle barrel, but the tang that came with the new barrel didn't even come close to the old one.  So I got a 1 1/2" bar of steel turned the thread on the lathe, and used a hack saw and file to do the rest.  The result was similar to yours, Tom, but it sure took a lot longer.  Tool envy going on here....
D. Taylor Sapergia
www.sapergia.blogspot.com

Art is not an object.  It is the excitement inspired by the object.

Militant_Hillbilly

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Re: Machining a breechplug tang
« Reply #2 on: August 12, 2012, 06:50:22 AM »
What would be the proper steel to use for the tang?

Offline Bob Roller

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Re: Machining a breechplug tang
« Reply #3 on: August 12, 2012, 02:16:11 PM »
 Forget the band saw and just use the milling machine. That barrel I
let Tom Merkley have had a breech plug that done in 40 minutes including turning
and threading.

Bob Roller

Offline SuperCracker

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Re: Machining a breechplug tang
« Reply #4 on: August 12, 2012, 03:11:26 PM »
OHHHHH, I know what I'm making this week!

Thanks, it's great because it's simple
"These Crackers are nomadic like Arabs and are distinguished from savages only in their color, language and superiority of their depraved cunning and unruliness.'' Gov Zespedes FL, 1780

Offline Dphariss

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Re: Machining a breechplug tang
« Reply #5 on: October 19, 2012, 03:49:52 AM »
Split nut is a great idea.
If I make a breechplug I fit them while still in the lathe till everything is pr  then machine on the barrel to set the top of the tang and rough the rest. Then finalize off the barrel with a tapered end mill. This is where that split nut would come in handy.
The bandsaw would be nice too. Could make fewer chips that way on short tangs anyway.






Dan
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Offline TMerkley

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Re: Machining a breechplug tang
« Reply #6 on: October 24, 2012, 08:31:45 AM »
Forget the band saw and just use the milling machine. That barrel I
let Tom Merkley have had a breech plug that done in 40 minutes including turning
and threading.

Bob Roller

Works pretty dog gone good Too!

Offline Mark Elliott

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Re: Machining a breechplug tang
« Reply #7 on: November 30, 2012, 01:16:58 AM »
I like the split collar idea.   I will have to order a couple.   However,  I am pretty sure I could do the same work, almost as fast with a hacksaw and a file. :D   Of course,  I would sweat more.