The Firing Line Forums

Go Back   The Firing Line Forums > The Skunkworks > The Smithy

Reply
 
Thread Tools Search this Thread
Old April 4, 2012, 06:37 AM   #1
2_Grumpy
Junior Member
 
Join Date: September 24, 2011
Posts: 9
Can a bolt face be rebuilt?

hi,

i have a m17 rechambered for .243. The face of the bolt has some pitting around the firing pin hole. The primer of a fired case expands into the pitting and then the extra length makes it difficult to insert in the reloading press.

So My question is, can the bolt face be built back up and machined to the right spec's or do I put up with it?

cheers
2_Grumpy is offline  
Old April 4, 2012, 06:43 AM   #2
hooligan1
Senior Member
 
Join Date: July 18, 2010
Location: Independence Missouri
Posts: 4,582
I'm sure it's possible, smiths talk about welding the firing pin hole closed and then redrilling it in true dead center, on some accurate rifle actions,,, hope this helps.
As far as where to send it? I'm not sure, I have'nt contacted any Gun Smiths in a long time, that did any work for me.
__________________
Keep your Axe sharp and your powder dry.
hooligan1 is offline  
Old April 4, 2012, 06:51 AM   #3
tango1niner
Senior Member
 
Join Date: March 5, 2009
Location: NY
Posts: 316
Is the primer flattened and flowing into the pit? If yes it sounds as if you have a pressure problem. If the primer is backing out of the pocket but not flattened you may have loose primer pockets or worse yet a headspace issue. A worn firing pin hole can be bushed. I would not weld on a bolt face/head as you could/would change the heat treatment qualities of said part.
tango1niner is offline  
Old April 4, 2012, 07:19 AM   #4
2_Grumpy
Junior Member
 
Join Date: September 24, 2011
Posts: 9
The primers are not pressure flattened, the primer does flow into the pits even with the lowest loads, but not as bad.
2_Grumpy is offline  
Old April 4, 2012, 09:41 AM   #5
Wyosmith
Senior Member
 
Join Date: December 29, 2010
Location: Shoshoni Wyoming
Posts: 2,713
Yes they can. I have done it several times.

However if the primers are not flowing into the gas cuts to a point they are causing problems you are better to leave it alone.

If you do need to fix the face because the cut is too deep it's a good idea to face the bolt back about .020" and then set the barrel back a turn and re-chamber. When you remove .020" the extractor will still work fine and in most cases facing back .020" will eliminate the pits or at least make them so minor that they are no longer a problem.

In the most extreme cases you may need to bush the entire bolt face and re-machine it to factory specs, but a new bolt is cheaper, so I only do that kind of repair when the gun has some provenance or special value, so that the customer doesn’t want to replace any parts. If you were working on Alvin York’s personal rifle such a repair might be justified, but in 99.9% of these cases you should just get a new (or newer) bolt.
Wyosmith is offline  
Old April 4, 2012, 11:39 AM   #6
Gunplummer
Senior Member
 
Join Date: March 11, 2010
Location: South East Pa.
Posts: 3,364
Then you need a shorter F/P on some models. You are right about a new bolt being the cheapest way to go.
Gunplummer is offline  
Old April 4, 2012, 02:04 PM   #7
edward5759
Senior Member
 
Join Date: September 15, 2009
Location: Phoenix, AZ. 30 miles from water, two feet from Hell.
Posts: 355
The last one I did was about $300.00 dollars.
I did the TIG filling, and machining. Then sent it out for heat treating, and re-blueing. came out nice but like others have said it's cheaper to buy a bolt!
__________________
Failure is part of success!

This year will go down in history. For the first time, a civilized nation has full gun registration. Our streets will be safer, our police more efficient, and the world will follow our lead into the future!" -Adolf Hitler,1935"
edward5759 is offline  
Old April 4, 2012, 03:11 PM   #8
brickeyee
Senior Member
 
Join Date: December 29, 2004
Posts: 3,351
Quote:
smiths talk about welding the firing pin hole closed and then redrilling it in true dead center, on some accurate rifle actions
Only if they are crazy.

Welding on a bolt near the lugs is a really bad idea.

A bolt with rear locking lugs might be OK (though they are not normally considered great candidates for high accuracy), but not a bolt with front locking lugs.

Even the possibility of altering the heat treat in the bolt and locking lugs is not worth welding near the lugs, and the bolt face is near the lugs on a front locking bolt.

The bolt face is bored and bushed, then a new firing pin hole drilled.
The bushing can be a press fit to eliminate the additional work of threading (and the loss in strength compared to solid metal).

The bushing normally has a larger diameter at the firing pin face, then steps down at the rear.
This allows the flange on the bushing to transfer more of the load to the machined back bolt face.

Last edited by brickeyee; April 5, 2012 at 01:36 PM.
brickeyee is offline  
Old April 5, 2012, 01:07 AM   #9
2_Grumpy
Junior Member
 
Join Date: September 24, 2011
Posts: 9
Thank you to you all.
2_Grumpy is offline  
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 05:35 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
This site and contents, including all posts, Copyright © 1998-2021 S.W.A.T. Magazine
Copyright Complaints: Please direct DMCA Takedown Notices to the registered agent: thefiringline.com
Page generated in 0.05131 seconds with 10 queries