Help with Belgian proof marks on a big bore percussion muzzleloader.

[Zonie]

I'm sorry to admit that I can't help you with the odd stamp - it does not fit any Belgian or British crown shape.

However, I CAN help you with the proof loads under the Belgian Proof Rules of 1846 and 53 - covering the putative era during which your gun was likely made. Your figure is in bold...

Gauge 1st Proof 2nd Proof

6 28 grams 18 grams
8 26 - 17 -
10 24 - 16 -
12 22 - 15 -
14 20 - 13 -
16 18 - 12 1/2

18 17 - 12 grams
20 16 - 12 -
22 15 - 11 -
24 14 - 10 1/2
26 13 - 9 1/2
28 12 - 8 1/2

1 gram = 15.4gr. Your First proof load will be 160gr of whatever you use in a shotgun - probably 3Fg.

Over to you.

I think you highlighted the 18 bore rather than the 8 bore?

As for proof loads, Dixie Gun Works catalog shows both Provisional Proof loads and Definitive Proof loads for both the 18 guage and the 8 guage barrels.

For the 18 guage barrel the Provisional load was 273 grains. It does not show a Definitive proof load for the 18 guage but it does show one for a 17 guage barrel that being, 150 grains of powder with 1 1/3 oz of shot.

For the 8 guage barrel the Dixie listing shows a Provisional powder load of 481 grains with a 812 grain ball. The definitive proof load for the 8 guage is, 270 grains of powder under a 1057 grains of shot (2 5/12 ounces, their number).
The chart goes on to say a Service load for the 8 guage is 135 grains of powder with a 1 15/16 ounce load of shot.

After giving this data I'll also give my advice. Do not proof test the barrel with anything greater than the definitive proof load.
If it were mine, I would not even do that.
Proof tests over-stress the barrel to prove it won't blow up but in doing this the test itself can look successful but in fact damage the barrel making it more dangerous to shoot.
My choice of a test would be to load the barrel with something like a 150 grain powder charge and 2 1/4 ounces of shot. If it withstands this load without showing any signs of swelling or cracking I would then limit my powder loads to 135 grains of powder and 2 ounces of shot. I would test for cracking by doing a "ring" test where the bare barrel is struck lightly with a piece of steel. If it rings, it is half way done with my non-destructive testing. I would then use a penetrant inspection fluid to visually find any cracks that might exist. If there were no cracks, I would say the gun is safe to shoot with a Service load.

 

[Ironoxide]

Zonie thank you for the data and advice. The 18 bore probably got highlighted by mistake, the gun is 8 bore.

I agree that original proof loads appear a massive overkill. Specially the Provisional load. I think your advice to test the gun with 150 grains of 3f and 2 1/4 ounces of shot is a good one.

I've ordered a dye penetrant kit. Do you think it is worth testing the barrel before "proofing" ? Regarding a "ring" test I only heard about using it in connection with double barrel rifles to check if everything is soldered properly. This is a single barrel gun. The barrel rings very nicely.

Now I'll have to build a wooden contraption to hold the barrel during the test and hit the cap when a cord is pulled. The stock requires some repairs before I can subject it to any serious recoil. I will test the barrel first to find out if the gun is worth working on. I wouldn't want to spend lots of time strengthening the stock and then find out the barrel is junk.

 

[TFoley]

Zonie thank you for the data and advice. The 18 bore probably got highlighted by mistake, the gun is 8 bore.

It is a mistake.

Sorry.

Zonie, please delete my post.

 

[Zonie]

I will delete it but only IF the actual data you posted is incorrect. Highlighting the wrong load isn't enough reason to remove the information you posted as there are some people who might find it useful. Please review the information in the chart and let us know if it is right.

 

[TFoley]

Yes, it is right - taken directly from Gun Digest 32nd edition 1978, page 131.

 

[Ironoxide]

I found another mark in the lock. It is letters GL and a crown. On the photo below you can't see the crown as the spring obscures it:

I believe it is an early symbol of Georges Laloux a firm active from 1836 to at least 1908. His later mark is a bee with letters G L on its wings. According to http://www.littlegun.be/arme belge/artisans identifies l/a laloux georges gb.htm the company specialised in converting military arms for civilians and they made good quality but basic arms for all purposes. One of the marketing leaflets that are shown on littlegun advertises they make "flintlock hunting arms for Africa". It is conceivable that they would make a percussion version of such a gun too.

Interestingly all pictures of other guns made and converted by them I saw have no engravings and are very utilitarian for the age when even the cheapest guns made by others featured low quality engravings.

I still don't know what is the symbol on the barrel, but I suspect it may be a barrel maker's mark.

 

[Ironoxide]

Well, life got in the way of things and two years have passed, but I've the gun in a pretty good condition now. Today I shot it properly for the first time and it is a pleasure to shoot. The sound of such a big bore gun is quite unique!

I thought people would be interested in how things turned out. Regarding the stock it is properly glued with acraglas and steel rods. The barrel has been rust blued lightly (about 12 coats) without polishing so it has retained an "old used gun" look. After bluing I discovered the barrel is made of twist steel! I wasn't expecting that! The nipple was made later and it is not blued yet.

I've "proofed" the barrel with 250 grains of 2f powder, a cork wad and 2 ounces of shot followed by another cork wad and some linen to hold it all together. In the end I didn't do a dye penetrant test. I decided it is a bit pointless on a twist steel barrel. Specially that it rings well and I don't plan ever using more than 135 grains of powder with a round ball.

I also remade few screws that were mangled by previous owners. I had to make special screwdriver tips for them too. You can see on one of the photos I still have to make two extra tiny screws that hold the barrel wedge plate.

I was casting other bullets yesterday and just before I was done I cast some 0.805 balls I ordered a custom mold for from a maker in UK. I'm happy to report the mold casts very well, but requires proper care when casting as it aligns using a brass lip rather than steel pins. I imagine one could damage it by slamming it shut repeatedly. So I always try closing it gently. Balls measured 0.802 from 30:1 tin-lead alloy. I know one is supposed to use soft lead, but that's what I had on hand in a molten state. I also read tin-lead balls were in use for dangerous game. The ball ended up weighing around 850 grains if I remember correctly!

I also took 3 patching materials (16,14 and 8 thou). The gun's caliber mark is 20.4mm (0.803). I initially measured it slightly larger at the muzzle, but it definitely is 20.4mm)(803thou) inside, because even with the thinnest, we'll lubricated patch it took heavy hammering to seat the ball. I would need a brass ramrod to use it with a patch. However, imagine my surprise when I discovered a naked round ball can be loaded fairly easily and stays on the powder. I may try a cork wad in front of it next time just in case.

Accuracy wise I had only 4 balls with me. I shot 2 patched and 2 u patched. I started with 80 grains of 1.5fg and ended up on 135 grains. I was shooting from 30 meters and elevation of course varied, but all balls ended up on the same vertical line! So I'm quite pleased.

Here are some photos for your viewing pleasure

However, I had one problem with the gun. If I pulled the trigger gently the hammer would fall to the safe position and it would not be possible to fire the gun without recocking and giving it a quick trigger pull. Does anyone know how to possibly fix it?

 

[user 55620]

With my old eyes it looks like UB with a damaged stamp.