Proof load

[peter nap]

I'm finishing up an old Belgium double 14 ga tonight. As far as I can tell, the Breech is good but somewhere along the line the left nipple hole was opened up and rethreaded to .265. I found a .265 nipple and it;s a snug fit.

Time to proof it. What load should I use?

[shunka]

Mr Dear Monsiuer Nap -
I do not pretend to know the european proof loads, especially as discussion of this topic is hot and heavy across the various ML forums.
There is a lot of discussion that a heavy proof load, while not "popping" at the time, may actually stress the gun "beyond what you shoulda" and possibly set it up for future failure.

However I will be happy to share what I've found -

the old standby from Dixie Gun:
Double Charge, Double Ball, butt in tire, in a pit, fired with a string.

also I picked this up from Jim Watson on The High Road:
---
Belgian proof law of 1853 called for three proof tests of a Lefaucheux pattern pinfire:
First proof, rough barrels before joining: powder 2/3 the weight of a bore diameter ball. For a 16 gauge, that is 2/3 of an ounce, or 18 grams powder. I assume the projectile stayed the same as in 1840, a ball not smaller than 0.6mm less than bore diameter.
Second proof, rough barrels after joining: 2/3 the first test, 13 grams powder.
Definitive proof of finished gun: same, 13 grams.

The definitive proof is approximately a triple charge. It is my opinion that those loads would destroy a period piece or as mykeal says, weaken it rather than proof it.

You can inquire at
http://www.doublegunshop.com/
for advice from braver souls than me.
------------------------------

I would be inclined to chat with the fellers at double gun and also ask
over at http://www.americanlongrifles.org/forum/
There are some serious professional names over there in the LongRifle page,
I have been able to chat with builders that I previously only read about in magazines.

yhs
shunka

[northmn]

Proofing an original does create an interesting issue. You want to be able to shoot it safely but do not want to ruin the gun. Here are the most likely scenerios. You may double charge the powder, the shot or two loads. Personally on an original I would want to shoot I would test it with a double charge of powder. What constitutes a double charge is basically what you determine is the best load for the gun. For a 14 gauge about 85 grains of 2f should be plenty for a single charge if you are going to use the old equal shot to powder measure formula. Personally I feel that that formula was developed for use with 1f in larger bores like the 14 and over as it used to be a popular shotgun powder. Many today are using less powder, like may 75 grains of 2f with 1 1/8 oz of shot. I tried 1f a few years ago and it worked OK, but was hard to get. Use of 1f in an original makes sense as it is lower pressure.
The 14 ga is a very nice upland gauge as you do not have to reach so far for the hammers and yet will handle a reasonable charge. Good luck, have fun.

Northmn

[mooman76]

For a proof load I would go 10 -20% over max that you would shoot or at the bare minumum I would use what you would shoot max. Gun in the tire thing of coarse.

[JMtoolman]

I too have proof some origional doubles but I never did it while the barrels were in the stock. I was concerned that I might ruin the origional stock. Insted I loaded the barrels and set them upsice down on a board with the breeches against a heavy lead brick, another brick was placed on the barrels. The nipples were placed on a small amount of black powder and a train of smokeless powder was used to set it off. Do one barrel at a time, and I never had one blow on me. Best regards, the toolman.

[peter nap]

Thanks guys!
I'll let you know how it comes out.

[longbow]

Peter:

Not sure if this is of use or not as it is for rifle but... here it is anyway:

http://www.iowatelecom.net/~toadhall/toad_hall_rifleshop.htm

He says about half way down the page that he proofs with two patched round balls and double powder charge.

Besides which if you haven't seen it, it is a great site!

Longbow