Author Topic: Metric breech threads  (Read 1323 times)

Offline msellers

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Metric breech threads
« on: November 09, 2018, 07:29:57 PM »
Ok, so if this question is in the wrong section please move or delete. I have an old barrel I asked about recently in a different section, that from all my measuring and test fitting is a metric threaded breech. Based on the thread chaser that easily fit into the breech it appears to have been tapped for a m18x1.5 thread. Has anyone seen this before, or know of a breech plug with this threading, I haven't located one in my searches. I am guessing that I will have to build one to this spec, but wanted to reach out to you all first.
Thanks in advance,
Mike

Offline 45-110

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Re: Metric breech threads
« Reply #1 on: November 09, 2018, 07:51:34 PM »
way more precise to use a metric thread gage to verify the pitch, not a thread chaser.

Offline M. E. Pering

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Re: Metric breech threads
« Reply #2 on: November 09, 2018, 08:05:44 PM »
Are there any other markings on the barrel?

Offline msellers

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Re: Metric breech threads
« Reply #3 on: November 09, 2018, 08:13:26 PM »
No markings at all. And I verified with a metric thread pitch gauge as well. But I only have the crappy one with my cheap die set. Will try and track down a better set, and verify again

Mike

Offline Bob Roller

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Re: Metric breech threads
« Reply #4 on: November 09, 2018, 08:40:06 PM »
No markings at all. And I verified with a metric thread pitch gauge as well. But I only have the crappy one with my cheap die set. Will try and track down a better set, and verify again

Mike
Possibly a pipe thread of some kind but aren't they usually tapered?
11/16 is about the closest fractional size I can see in the "Special Thread"
taps of Travers Tools catalog.

Bob Roller

Offline rich pierce

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Re: Metric breech threads
« Reply #5 on: November 09, 2018, 09:14:55 PM »
Is the “old barrel” pre-1860 or pre-2000?
Andover, Vermont

Offline msellers

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Re: Metric breech threads
« Reply #6 on: November 09, 2018, 11:00:04 PM »
Is the “old barrel” pre-1860 or pre-2000?
I wish I knew better, it is definitely pre 2000. It has some pretty heavy corrosion putting towards the breech end. However, the threads and crown appear more recently cut.
Mike

Offline DutchGramps

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Re: Metric breech threads
« Reply #7 on: November 09, 2018, 11:48:20 PM »
This  is most probably Metric fine M18x1,5, used in Europe after the French revolution ;D
Real bikes are kick-started....