Nice English hammer gun. Out of proof?
 

I looked at a very nice English hammer gun today. It is priced low. The gun does not have a makers name. The chambers measure 2 3/4" with my Galazan gauge. Everything I see on the barrel flats shows 2 1/2" proof.
Am I correct?
Thanks Dave

If the barrels have plenty of material left and no big pits get it and go shoot the thing.

The 1 1/4 ounce proof would usually indicate more than 2 1/2" chambers. What is the bore diameter? Is it still .719?

Have the wall thickness measured. It does not appear to have been London or Birmingham reproofed for 70mm or 2&3/4 as required in the UK. Good luck.

The picture isn’t super clear to me. It looks like it has a British reproof mark on it. I can’t tell, but does that a 5 ton mark? Anyway, have the bores measured to be safe.

Ken

2 1/2" chamber, 1 1/4 ounce original proof barrels are not unknown, but are unusual.

It was originally proved 1925-1954 with 2 1/2" chambers for 1 1/4 oz.
1 1/4 oz. would be the standard for 2 3/4" chambers for a max. service load of 3 3/8 Dr. Eq. with 1 1/4 oz. shot with a pressure of 3 1/2 tons = 10,640 psi
Bores then were 15/1 or .685" - .692"

It was reproved (Crown over R) 1954-1989 by the London Proof House (the arm and sword over NP, but prior to application of the date code mark which started in 1972) still with 2 1/2" chambers for THREE Tons; now with a bore of .719". 3 TONS would be the standard for 2 1/2" chambers with a max. service pressure of about 9000 psi

That is substantial honing so wall thickness measurements are critical.

https://photos.smugmug.com/Proof-Mar...B38C781D-M.jpg

Thank you Drew, That is the information I was hoping not to get, but expecting.
I'll pass on this one
Thanks again, Dave

The short answer is that it was in proof sometime before 1989 after the barrels were opened approximately 3 gauges. As everyone said, you must measure the walls. It could be very thin as reproofed, and may have been honed again for some reason. My bet is that you will find some very thin barrel walls at some point, particularly in the front half.

I edited my post. The application of the date code mark by the London Proof House started in 1972 so the gun was reproved prior to then, and bad things happen to barrels in > 50 years.

Was this gun a 16 bore? How does someone hone .050" and expect there to be any wall left?

Edgar: the 12 over C in the diamond was marked at the time of the original proof. 15/1 however would be considered a 14 bore.

The Proof House once thought a mistake was made, but on further examination found that there was not, nor has there ever been ;)

Thank you, Dr Drew. I missed the sideways 12, but never figured to look for a 12, when .719 is so much smaller.

the 12 over C in a diamond seems to indicate chambers longer than 2 1/2"

12 over C was used starting in 1887 for 2 1/2", 2 5/8" and 2 3/4" chambers. 12 over LC was for 3" chambers
https://www.vintageguns.co.uk/magazi...roof-4-london-

from The Standard Directory of Proof Marks

https://i.imgur.com/HewpVhm.jpg

There is a lot of "supposing" going on here when a wall thickness gauge and a bore micrometer would answer all questions. I would not pass on a 1 1/4 ounce proved English hammer gun without measuring it. They are not that common, but then, Dave Knows that.

Thanks Daryl. I did some more looking. Burrard was no help. We discussed this issue some time ago on DoubleGun and Miller said he'd seen 3" chambered guns marked 12 over C and also over LC.
I couldn't find confirmation but it appears likely the significance of LC changed at some point.
After 1954 there was neither C nor LC, just 12 in the diamond.

Drew, I have a circa 1900 Cashmore Nitro with the 12 over C in a diamond. It is also marked 3" Cases.
Also, here is a Betts with similar markings.

https://i.imgur.com/4urnO7y.jpg

https://i.imgur.com/uPTDU2e.jpg

https://i.imgur.com/12R9d9y.jpg

I think the British enjoyed confusing we Colonials. Your directory suggests that the LC was used only after 1925.
The Betts date code looks to be 'O' for 1934-35

Your Cashmore would be 1896-1904 with the 1 1/4 OZ. MAXM

A 1887 - 1896 Cashmore for 3 1/4" cases marked 12 over C.

https://photos.smugmug.com/Proof-Mar...DSC02195-M.jpg

Maybe we should say that prior to 1925 the 12 over C in a diamond meant chamber length of 3" or longer.

This is a 16g with pre-1925 proof with 2 1/2" chambers

https://photos.smugmug.com/Proof-Mar...925Proof-M.jpg

Engelhardt in the 1962 Gun Digest "European Proof Marks, Proof in Great Britain" stated that the 12 over C was not used prior to 1925, which is obviously incorrect, and didn't mention 12 over LC.

I think we can say that gauge over C means "standard chamber length" - 2 1/2" to 3" (after 1925 anyway) and 'LC' means 'long chamber"

With this circa 1900 Greener, maybe the 12 over C in a diamond actually means a chamber length over 2 1/2". We see that mark in guns with 3 1/4" chambers prior to 1925. This 12 over C mark is for 2 3/4" chambers prior to 1925.
https://i.imgur.com/uYEutY0.jpg

a 1925 or later example. Lots of questions , but luckily we have lots of examples.

https://i.imgur.com/a4f9hbb.jpg

Can we now say that 12 over C in the diamond, prior to 1925 means a 12 ga chamber that could be anything from 2 1/2" to at least 3 1/4" [probably more] . Then after 1925 the 12 over C in the diamond would be proper for chambers up to, but including , chambers of 3". Then the 12 over LC would be used for longer than 3" and would also be marked with numerical length ?

A later thought is that the gauge over C in the diamond just meant a gun with chambers [any length], Earlier there were centerfires and of course muzzle loaders that did not have chambers, thus the C designation under the gauge .

Thanks Daryl.
The author didn't try to address the C here :(
https://www.vintageguns.co.uk/magazi...roof-6-london-

Found the 1904 Proof House Revisions in The Gun and Its Development, 1907
http://books.google.com/books?id=3HMCAAAAYAAJ&pg=PA290
No specific mention of the 12 over C chamber lengths
LC is for chambers "more than 3 inches"

https://photos.smugmug.com/Proof-Mar...t%201907-M.png

So the 1925 date is incorrect

Good find , Drew, in the 1904 revisions. Longer than 3” seems right for LC. Maybe up until that time. LC did not exist and gauge over C in the diamond could be any chamber length. I think we are making progress.

The 1896 Rules with both C and LC
https://books.google.com/books?id=inQCAAAAYAAJ&pg=PA4

https://photos.smugmug.com/Proof-Mar...%20Rules-L.png

Rule #22 if for 3" or longer chambers

Rule #40 specifies the 'C' but does not mention chamber length

SO it appears that the Rule was changed for LC in 1904

Drew, how did you decide that the rule for LC was changed in 1904. It seems that the LC you show above is part of the 1896 Rules.

This states under the 1887 - 1896 Rules LC is 3" or longer
https://www.vintageguns.co.uk/magazi...roof-4-london-
I couldn't however find the Rules published

96 - 04 Rules 3" or longer
Rule # 45 refers to Rule #22
https://books.google.com/books?id=inQCAAAAYAAJ&pg=PA3#

04' Rules state LC for is more than 3"