lock fit to barrel

[Daniel]

Ok , I took a piece out to the range Friday. After the first shot I noticed smoke coming from side plate side
around the barrel. I took a hard look and the lock was not tight against the barrel. So no more shots. This is a custom built piece I bought.
At home I removed the lock , and saw too muck wood still. Removed the excess and inlet lock a little deeper
at the nose. Still a gap. Inlet a small amount at rear to level. Still a gap. I put a straight edge on bolster, not true. Filed a little.
Still not flat. So the mechanic came out. I cut a thin copper shim. Fit it to the bolster and temporary fit it there.
In stalled the lock and no gap. Yes !  Now the question is this a good/right way to make the repair ?

[Ky-Flinter]

Hi Daniel,

Is the gun a flintlock or a caplock?  If it's a caplock, there's more trouble than just an ill fitted lock.  I suspect it's a flint and the smoking is burning priming powder that made it's way into the gap.

The bolster and barrel faces should be tight at the same time the inside of the lockplate meets the wood of the lock mortise.  With the shim in place is the lock plate supported?  As you file the bolster, you could run into other issues.  If a caplock, will the hammer still line up with the nipple?  If a flint, you will likely need to file the inside edge of the frizzen the same amount or a little more than the bolster, so it doesn't bind on the barrel.

If it was mine, I'd soot the inside of the lock so I could see exactly where wood is contacting the inside of the lock.  Whether to stick with the shim is a judgement call, depending on how much wood would have to be removed.  it ain't the best, but with the shim in place, if the lock plate is solid in the mortise, you should be ok.

-Ron

[J. Talbert]

A drawback to the shim, assuming we're talking flint, is that it will create a gap between the barrel and the edge of the frizzen.  I'd have to see how big that is before I'd decide whether the shim is a suitable fix.

Jeff

[Daniel]

I have filed the shim very thin. The frizzen fits good to the barrel . Lock plate is supported good too.
There was only a gap about the thickness of a finger nail to begin with. Never saw it .

[Jerry V Lape]

Is the bolster flat?  Seems from the description the shim might be making up for a bolster which is not flat.  Have you taken the pan/bolster off the lock plate and checked to see that it fits true to the barrel by itself?  Are the internals clear of the wood all the way through their cycling?  The advice to get some inlet maker on the plate and internals is where I would start if the bolster is flat.  Don't ignore the possibility the cock may be rubbing on the stock above the lock plate.  Also, does the lock plate rock from top to bottom in the inlet? 

[Daniel]

All very good questions. The lock did rock back and forth. Bolster is flat.
The sear is rubbing and I need to inlet it a bit deeper and open the hole a bit.
I noticed that after shooting when I went to pull hammer back I had a slight click.
I will have to refinish the lock area, but no problem it's oil on walnut.
Hammer is rubbing too.

[smart dog]

Hi Daniel,
This is a serious problem resulting from someone building the gun either not knowing what he was doing or very careless. There can be no gap between the bolster and barrel. A finger nail width is huge.  The only way to solve this is to inlet the lock deeper until the bolster fits snug.  No gap, no rocking, nothing but a snug perfect fit.  It may mean you have to shave down the lock moldings if the lock fits too deep after inletting.  Do you have 2 lock bolts or one?

dave

[Daniel]

3 lock bolts. I have inlet the lock deeper and no gap now .
Yea, serious is right. I do not need a gun blowing up on me.
Thanks guys

[Daniel]

Only thing I need to do is smooth out my inletting and take the moulding down a bit.
Gotta make my lock screws shorter too.

[Daniel]

 Done. Nice and tight. Thank you all again .

Daniel