Author Topic: breech plug fit  (Read 2316 times)

Offline jrb

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breech plug fit
« on: September 11, 2016, 06:46:40 PM »
I've got an unused  Green Mountain 42" swamped B weight barrel with a 5/8 x 18 threaded breech hole.  I've tried breech plugs from Track of the Wolf and the Log Cabin Shop. They're a little too sloppy fit in the threads, when the plug is screwed say, 3/4 way in, they're loose enough that they rattle if I try wobble them with my hand. Anyone make a custom  plug? or ?

Offline D. Taylor Sapergia

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Re: breech plug fit
« Reply #1 on: September 11, 2016, 06:54:31 PM »
One thing to watch for is the length of the female thread in GM  barrels.  They are up to 3/4" in depth...WAY TOO LONG!  I trim those barrels off to 1/2" and make the plug to fit.  I've never seen one that rattled though??
D. Taylor Sapergia
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Offline Mark Elliott

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Re: breech plug fit
« Reply #2 on: September 11, 2016, 10:14:28 PM »
I usually buy my breech plug blanks (for extra long tangs)  from TOTW and have never had one that was loose like you describe.    I think I would talk to TOTW about it.   

Offline Dennis Glazener

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Re: breech plug fit
« Reply #3 on: September 11, 2016, 10:52:00 PM »
Two different plugs from two different vendors? I would check the GM barrel to make sure its correct. Are you sure you you are getting the right size? Almost sounds like you have a 9/16 X 18 plug going in a 5/8 X 18 hole! I have never gotten a plug that was that loose in a barrel.
Dennis
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Offline bgf

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Re: breech plug fit
« Reply #4 on: September 11, 2016, 11:08:25 PM »
Something is wrong!  Not only are Green Mountain breech threads long as said, but they are TIGHT!  It took 4x as long to breech a GM as a similar Rice barrel.

Maybe someone ran a normal hardware store tap into your GM, possibly even a vendor to cut down on complaints from users?  It might still be ok, but I understand your concern.  Does it tighten up at the end or only when fully seated?

Also, check threads as Dennis said.  5/8 seems small for breech on swamped barrel.