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Forums10
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Jun 14th, 2026
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Joined: May 2004
Posts: 2,153 Likes: 60
Sidelock
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OP
Sidelock
Joined: May 2004
Posts: 2,153 Likes: 60 |
I just purchased a beautiful Francotte with very fine checkering, lots of engraving and chain link pattern on the Damascus barrels. I would love to shoot it but I am not sure if the wall thickness is safe. I have the vertical wall thickness gauge from Galazan most of you are familiar with. It has the three vertical rods for different gauges. I do know how to use it and I took measurements every three or five inches which I will list here. I would appreciate comments from knowledgeable members to guide me. I reload lower pressure 12 gauge loads. The bores measure .733 and .736 and the metric proofs convert to .728. I realize nobody can tell me if it is safe to shoot however I would like to hear from you based solely on the numbers below. Thanks all!
Measurements are from the breech:
Right barrel Left Barrel
3" .115 .097
6" .067 .064
9" .048 .046
12" .043 .034
15" .035 .023
20" .032 .022
It is marked 2 3/4" chambers and the rest of the measurements come in as safe in the areas I did not list.
So many guns, so little time!
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Joined: Mar 2002
Posts: 7,908 Likes: 682
Sidelock
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Sidelock
Joined: Mar 2002
Posts: 7,908 Likes: 682 |
Looks like a very safe to shoot gun based on those measurements. .
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1 member likes this:
builder |
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Joined: Jan 2002
Posts: 966 Likes: 129
Sidelock
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Sidelock
Joined: Jan 2002
Posts: 966 Likes: 129 |
The NRA has proven itself unreliable and corrupt. Period.
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1 member likes this:
builder |
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Joined: Jan 2020
Posts: 856 Likes: 225
Sidelock
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Sidelock
Joined: Jan 2020
Posts: 856 Likes: 225 |
Any pits? Share some pics, sounds like a beauty. RST says their 2.5” loads are 7500psi or less according to last phone call I made to them.
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Joined: Oct 2006
Posts: 2,393 Likes: 715
Sidelock
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Sidelock
Joined: Oct 2006
Posts: 2,393 Likes: 715 |
How long are the barrels?
.022 is awfully thin if that spot is where the pressure spike is going to be (usually around 9” from the muzzle).
I suppose it could be safe, until it’s not. Being that thin, as far down the tubes as your showing, is going to make dent removal or repair sketchy if you happen to damage the barrel. Especially when it comes to soft damascus barrels. Just food for thought.
Theres a very good reason that barrel guys and knowledgeable gunsmiths in general don’t recommend a MWT below .025.
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Joined: Jan 2020
Posts: 856 Likes: 225
Sidelock
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Sidelock
Joined: Jan 2020
Posts: 856 Likes: 225 |
Never seen a bulge or split 9 inches from the muzzle unless full of mud or snow(your probably screwed if you do that with any gun anyway!). I believe Churchill cut that spot on one of his with a razor to prove little pressure out there. Always good to have a gunmaker go over your gun and advise.
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Joined: Oct 2006
Posts: 2,393 Likes: 715
Sidelock
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Sidelock
Joined: Oct 2006
Posts: 2,393 Likes: 715 |
Never seen a bulge or split 9 inches from the muzzle unless full of mud or snow(your probably screwed if you do that with any gun anyway!). I believe Churchill cut that spot on one of his with a razor to prove little pressure out there. Always good to have a gunmaker go over your gun and advise. 9” from the muzzle is exactly where barrel specialist measure for MWT. They measure there, at that specific distance from the muzzle for a reason. It’s a crucial area. What kind of barrel work do you do?
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Joined: May 2004
Posts: 2,153 Likes: 60
Sidelock
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OP
Sidelock
Joined: May 2004
Posts: 2,153 Likes: 60 |
It is late here in NJ and I am beat. The barrels are 30". Sorry to have missed a very important point.
At 9" from the BREECH it is .048 and .046 for the other barrel. At 12" one barrel gets pretty thin and my hand will be there I think but half way at 15" it gets real thin at .023 and I have never measured but my hand has to be pretty close. The pressure is probably way down at that point I think. The bore is very smooth but I am sure it has been honed. I have inspected as best I can and the barrel walls look solid. The left bore is .736 meaning it probably has been honed .008". Maybe whoever recolored the Damascus barrels took too much off the outside in that area leaving .023 thickness at 15" from the breech. I am hoping to hear otherwise but right now I am feeling it is risky. After 20" from the breech, meaning the last 10" to the muzzle are at least .030 so that is no concern.
I hope my ramblings make sense.
So many guns, so little time!
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Joined: Mar 2002
Posts: 7,908 Likes: 682
Sidelock
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Sidelock
Joined: Mar 2002
Posts: 7,908 Likes: 682 |
General thought is that .025 is reasonable, .020 is where you start to take notice and below .020 proceed with caution. I shoot guns with .020 barrels. Where it is thin is as important and how thin it is. 20" from the breech is not a big worry for me. I do use "sane" loads. 5,000 to 7,000 loads will do everything I need. I shoot a Pape 20 bore with .016" & .020" walls, but that is at 26 & 27" from the breech, on a set of 30" barrels. In that gun, I have shot several thousand 7,200 psi loads. I would not shoot factory shells because I have no clue what pressure they might be. Reload and stay safe. I am more worried about recoil and stock damage than barrel wall thickness and pressure. Keep the pressure moderate and shot charge light and you will do fine.
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2 members like this:
Hammergun, builder |
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