Author Topic: Top of Lock Panel Behind Breech  (Read 2416 times)

Fiftyfour

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Top of Lock Panel Behind Breech
« on: November 16, 2017, 09:41:10 PM »
ln general, with an octagon breech, should the top of the lock panel behind the breech (each side of the tang)
be about at the height of the top of the barrel side flat? Thanks

Offline D. Taylor Sapergia

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Re: Top of Lock Panel Behind Breech
« Reply #1 on: November 16, 2017, 10:18:34 PM »
In general, yes, that's a good goal.
D. Taylor Sapergia
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Art is not an object.  It is the excitement inspired by the object.

Offline Mr. Bubbles

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Re: Top of Lock Panel Behind Breech
« Reply #2 on: November 16, 2017, 11:03:53 PM »
Just bear in mind that the various schools locate the locks differently, and orient them differently within the lock panel.  Lehighs and Bucks for instance tend to locate the locks rather high in the lock panel, and the touch hole high on the side flat.  In order to achieve that, locks are oriented in a slightly nose down position.  They typically have very narrow lock panel margins. 

Lancasters on the other hand, have bigger lock panel margins, orient the lock more parallel with the bore, and generally put the touch hole right about in the middle of the flat.

So the answer to your question is a general "yes" but there are nuances and variations within it too.

Offline smart dog

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Re: Top of Lock Panel Behind Breech
« Reply #3 on: November 17, 2017, 01:21:58 AM »
Hi Fiftyfour,
Use that rule as a very general guide that can be over ruled because of other considerations like lock placement.  Look closely at the lock panel behind the pan on the rifle below.  It just so happens that it lines up with the barrel flat but that was not the important consideration. Notice how the flat almost disappears behind the pan. That is because the flat is thinned and the stock also tapers in exposing more of the lock bolster as it gets closer to the pan.  That thinning and tapering looks good and allows me to avoid the ugly notch you see on many guns needed to clear the flint cock. Clearing the flint cock was the first consideration, lining up with the flat happened by accident.

dave
"The main accomplishment of modern economics is to make astrology look good."

Fiftyfour

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Re: Top of Lock Panel Behind Breech
« Reply #4 on: November 17, 2017, 02:34:11 AM »
Dave
I have a few questions for you.
I looks like the pan fence is about a 1/4" inch forward of the end of the barrel, is that correct?
I did not know until somewhat recently that some lock plates that I assume are earlier, are not
Thicker where the cock is screwed to the tumbler. Is that what you are referring to when you
Mention notching and clearance for the cock?
Lastly, is there terminology that defines a lock plate that is thickened where the cock is fastened
And a plate that is not?
Thanks

Offline smart dog

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Re: Top of Lock Panel Behind Breech
« Reply #5 on: November 17, 2017, 04:11:44 AM »
Hi Fiftyfour,
The pan is about 3/16" from the end of the barrel because the vent hole has to clear the breech plug.  Of course it is correct.  On some locks, the pan is large such that the fence is lined up with the end of the barrel.  That is not the case with this lock.  No, I am not referring to any thickening in some lock plates.  All locks have a thick bolster, which is the metal you drill into for the rear lock bolt. The shoulder on the flintcock rests on that bolster when the lock is uncocked. To make clearance for that shoulder, you either do what I did or you cut a notch in the stock behind the pan.  I do not like those notches and have never seen one that looked good although there are plenty of original guns with notches cut.  I avoid the notch by slimming the lock panel flat to the point where it almost disappears, like in the photo, and also shaving in the wood of the lock mortice inward as it approaches the pan so more of the top of the lock bolster is exposed above the wood. That way enough of the top of the bolster is exposed such that the shoulder of the flintcock can rest on it without touching the wood.  Hence, no notch is needed and it all looks much nicer. 

dave
« Last Edit: November 17, 2017, 04:22:01 AM by smart dog »
"The main accomplishment of modern economics is to make astrology look good."