Author Topic: 'New' question on 3/8 liner or plug!!  (Read 3363 times)

Offline Roger Fisher

  • Hero Member
  • *****
  • Posts: 6805
'New' question on 3/8 liner or plug!!
« on: December 28, 2009, 06:00:18 PM »
Forgive me since I'm repeating myself.  I had a question on this putting a 3/8 liner or plug in a 45 cal 7/8 Oct barrel assuming the 5/16 x 24 hole is 'sloppy' ::)  Had only a few responses.  I'm blaming it on the holiday season and folks having other things to do.... Is there enough meat there to do this safely assuming again that the 5/16th was perfectly centered?

What is the consensus of opinion on this?  I'm sure more of you know one way or the other. I knew there was more than one reason why I like to use a 15/16th barrel ;D

Anyone?

Offline D. Taylor Sapergia

  • Member 3
  • Hero Member
  • *
  • Posts: 12671
Re: 'New' question on 3/8 liner or plug!!
« Reply #1 on: December 28, 2009, 07:22:57 PM »
Roger. i've just done the math.  You have barrel walls, assuming the bore is in the centre of the barrel, and your rifling is .012" deep,  of .23175.  I don't have enough experience with percussion drums to make a comment of it, but I will anyway.  If your threads are National Fine (3/8 x 24 or 32)and good, and the drum is supported well by the lock plate, the scenario should be ok.  With 24 TPI you will have a minimum of 5.56 threads engaging the barrel steel.  With 32 TPI that increases to 7.4 minimum threads in the barrel.
D. Taylor Sapergia
www.sapergia.blogspot.com

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

Offline Mad Monk

  • Hero Member
  • *****
  • Posts: 1033
Re: 'New' question on 3/8 liner or plug!!
« Reply #2 on: December 28, 2009, 09:34:42 PM »
Forgive me since I'm repeating myself.  I had a question on this putting a 3/8 liner or plug in a 45 cal 7/8 Oct barrel assuming the 5/16 x 24 hole is 'sloppy' ::)  Had only a few responses.  I'm blaming it on the holiday season and folks having other things to do.... Is there enough meat there to do this safely assuming again that the 5/16th was perfectly centered?

What is the consensus of opinion on this?  I'm sure more of you know one way or the other. I knew there was more than one reason why I like to use a 15/16th barrel ;D

Anyone?

Roger,

I went through the same thing with my .45 caliber Getz barrel in my Schimmel.  The original vent liner threads started to leak gas when firing.  So I took it to Dixon.  Drilled and taped it for the next size larger liner.  The liner flange occupies the entire width of the side flat.  Shot it a good bit after that without problems.  Being a RB barrel that is all that gets shot in it.  Being .45 caliber I don't shoot gonzo charges in it so there have been no pressure problems.  He warned me not to take the liner out during cleaning.  Just leave it be.  If the threads on this new liner go it would mean cutting off the breech end of the barrel and rebreeching it.  Would cost more than a replacement barrel.

Bill K.

Offline Roger Fisher

  • Hero Member
  • *****
  • Posts: 6805
Re: 'New' question on 3/8 liner or plug!!
« Reply #3 on: December 28, 2009, 09:46:07 PM »
Forgive me since I'm repeating myself.  I had a question on this putting a 3/8 liner or plug in a 45 cal 7/8 Oct barrel assuming the 5/16 x 24 hole is 'sloppy' ::)  Had only a few responses.  I'm blaming it on the holiday season and folks having other things to do.... Is there enough meat there to do this safely assuming again that the 5/16th was perfectly centered?

What is the consensus of opinion on this?  I'm sure more of you know one way or the other. I knew there was more than one reason why I like to use a 15/16th barrel ;D

Anyone?

Roger,

I went through the same thing with my .45 caliber Getz barrel in my Schimmel.  The original vent liner threads started to leak gas when firing.  So I took it to Dixon.  Drilled and taped it for the next size larger liner.  The liner flange occupies the entire width of the side flat.  Shot it a good bit after that without problems.  Being a RB barrel that is all that gets shot in it.  Being .45 caliber I don't shoot gonzo charges in it so there have been no pressure problems.  He warned me not to take the liner out during cleaning.  Just leave it be.  If the threads on this new liner go it would mean cutting off the breech end of the barrel and rebreeching it.  Would cost more than a replacement barrel.

Bill K.
Thanks Bill:  I am still pondering the matter.  Glad to hear you went down the same road and went to a 3/8 w/o a problem.  Am I correct in believing that your barrel in question was a 7/8?  This build (which I am not rushing at all) is at the point that she could be cut back/rebreeched and drum or vent redrilled and tapped.  Barrel, tang, lugs are in but no more! :) I do not remove vents for cleaning!
« Last Edit: December 28, 2009, 09:47:11 PM by Roger Fisher »

Offline Mad Monk

  • Hero Member
  • *****
  • Posts: 1033
Re: 'New' question on 3/8 liner or plug!!
« Reply #4 on: December 28, 2009, 10:08:12 PM »
Rog,

Yep on the 7/8" barrel.

When I bought that barrel I was told that I was pushing it a bit on wall thickness and should have gone with a thicker barrel in .45 caliber.  But I had no problems with it.  That rifle was my test gun for all of the powder work into 1998 when I was asked to switch to a .50 caliber 28" barrel.  But I kept shooting the .45 when I just wanted to shoot for pleasure.  It is a Getz barrel that dates back to around 1980.

Bill K.

Offline Mad Monk

  • Hero Member
  • *****
  • Posts: 1033
Re: 'New' question on 3/8 liner or plug!!
« Reply #5 on: December 28, 2009, 10:40:55 PM »
Rog,

I stand corrected here.  On a gut feeling I hauled out the .45 Schimmel.  Not a 7/8" barrel.  It is a 13/16" barrel in .45 caliber.

Bill K.