Can you safely weld a breechplug?

[Roger B]

So I've been building this Hawken since right after Sam retired & I've made every mistake known to man & fixed them all so far.  Unfortunately I am using a Large barrel with Bill's hooked percussion breech which has been a trial of my patience.  The breech is really roughly made externally.  While trying to make a more graceful transition at the front of the bolster where it loops back to the flat, things got out of control (even with a safe triangular file) & I got more of an ugly gash than a notch.  Polishing & blending helped, but it still irks me because it sticks out like zit on Sandra Bullock's behind & really looks amateurish.  Can I safely weld in a little fill just in that area & reshape it without compromising the safety of the breech plug? My guess is that the plug, tang & barrel are all 12L14.  I am about ready to have the lockplate, hammer, trigger bar, & plug & tang case colored, but doing that to this breech plug will just be like putting lace curtains in a porta potty.  It might fool you for a second, but after that there is no mistaking where you are.
Roger B.

[Dphariss]

So I've been building this Hawken since right after Sam retired & I've made every mistake known to man & fixed them all so far.  Unfortunately I am using a Large barrel with Bill's hooked percussion breech which has been a trial of my patience.  The breech is really roughly made externally.  While trying to make a more graceful transition at the front of the bolster where it loops back to the flat, things got out of control (even with a safe triangular file) & I got more of an ugly gash than a notch.  Polishing & blending helped, but it still irks me because it sticks out like zit on Sandra Bullock's behind & really looks amateurish.  Can I safely weld in a little fill just in that area & reshape it without compromising the safety of the breech plug? My guess is that the plug, tang & barrel are all 12L14.  I am about ready to have the lockplate, hammer, trigger bar, & plug & tang case colored, but doing that to this breech plug will just be like putting lace curtains in a porta potty.  It might fool you for a second, but after that there is no mistaking where you are.
Roger B.

The internal design of his breeches can cause problems. It was a Bill Large Hawken breech spitting out a nipple  that converted John Baird to flintlocks.
John had a couple of black spots on his nose as a reminder.
I am not sure that Large used 12L14. It might be 1144 based on some things he wrote. Its till cold rolled I am sure.
From the welding standpoint it has a lot of carbon.
Since we don't know what the breech is....
If you weld  you will have to do a full anneal.

Dan

[Daryl]

Dan - slow air cooling is not enough?

[Roger B]

What would annealing entail for this plug?  Are we talking a few hours in the oven at 400 degrees or so?  I have to say that the interior looks pretty much like any other plug I've ever seen.  Nipple seat seems OK.  I should have tossed it when I started building, but I thought that the rifle might be worth more if I kept it.
Roger B.

[Curtis]

Roger,

Just how big is the zit, I mean gash?  If it is not too large you could maybe undercut with a graver and inlay some mild steel.  If you leave eough to peen it at the joint once you clean it up it should never show.  Just a thought, no anealing necessary.

Curtis

[Roger B]

I like that idea Squirrelheart, but I doubt that Ican execute it.
Roger B

[bgf]

Picture, please -- you may be making a mountain out of a molehill .  I like the plug and peen idea if possible -- it worked OK for me on a couple of pieces.   

[Roger B]

Let me see if I can get one tonight & post it.  It isn't that terrible size-wise.
Roger B.

[Roger B]

Did a little searching on the net.  Welding 12L14 or 1144 is a bad idea, particularly in this instance.  Sulfur content in the steel causes porosity & weld line cracking.  Back to the drawing board.
Roger B.

[Dphariss]

Dan - slow air cooling is not enough?

Welding will make hard spots if the carbon is high enough. In welding really serious stuff to prevent this the area around the weld in preheated. This prevents the cold metal from acting as a quench medium. This from a friend who was a welder at a refinery.
Since the material is unknown its best to anneal since the breech is a critical part.
If it was all KNOWN to be low carbon it might weld OK with no problems. I just welded a RE Davis Twigg lock plate to a piece of 1018 and found no hard spots when reshaping. But the plate got pretty hot as the welding progressed. I don't know what Davis casts the plates from but it welded very nice and produced no pits to refill after polishing.

Dan

[Roger B]

The suppliers state that both of these steels anneal at around 450+ degrees C with an hour for each 25mm.  I got nothing that will do that.
Roger B.