doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Damascus small bore upland guns

Not to get in the middle of things here, but a quick search of the net revealed little info. Can anybody tell me where I might be able to find what pressures were used in these early damascus guns, say around 1900. To my understanding, SAAMI didn't come to be until 1926? I would assume the proof houses had info related to pressures. Please correct me if any of this info is wrong, A reference to read on the subject would be wonderful. I have DGJ back to '98.

doc06 Sherman Bell has done a lot of pressure testing on BP loads, there is probably some info in his articles in DGJ on service loads. From 1968 to 1979 Gun Digest had a series of articles on gun proof, there must be some info there on proof pressures, I have the articles, I will check and let you know what issue(s)

doc06 back again, check these Gun Digest if you have them
1970 Gun Proof in France
1975 Germany
1977 England
1978 Belgium
There is information in these issues on pressures, also powder charges and load weights used.

What year? What country? What proof marks does the gun have?

Proof evolved over the years. At one time, every one had their own standards. Eventually the Europeans agreed to a common standard, known as CIP today, with the Brussels' convention of 1914. However, the war stopped that approval in most countries, so it was not until 1924 that a common standard was officially set. Then you could have the gun proofed at various levels using either black powder or smokeless. This all gets much more complicated, but you get the picture.

The tests originally were designed around loads rather pressure. So a normal test would for example consist of 4x the black powder of hunting load. I am not sure when the tests were designed to meet pressure levels. But certainly no pressure gauges were available in 1914.

SAAMI is an American association. Officially, we have never submitted guns made here for proof to a government controlled test. In reality, litigation has guaranteed that they are in fact tested.

From Table XII of Belgian 1924 proof for Definitive Black Powder of Breechloading Shotguns.
28 Gauge, 23/4" Max Chamber, 6.4 grams powder, 28 grams Shot Charge
32 Gauge, 21/2" Max Chamber, 5 grams powder, 22 grams Shot Charge

The provisional proof loads were higher. Even the loads above are not expected to be fired but are for proof only.

Pete

james-l is correct about the Gun Digest articles. They are by Lee Kennett. This is the listing I have:

22nd Edition Czecheslovakia -1968
23rd Edition Austria Hungary & Austria - 1969
24th Edition France - 1970
25th Edition Spain -1971
26th Edition Italy - 1972
27th Edition Hungary - 1973
28th Edition Russia - 1974
29th Edition Germany -1975
30th Edition Military - 1976
31st Edition England - 1977
32nd Edition Belgium - 1978
33rd Edition India -1979

You can usually pick these up on eBay for under $5.00.

Pete

James - Proof from that angle is simple. The load referenced above is from Alliant, and listed as 2.5 Deq at 1090 fps. By dropping the powder charge to get into the black powder pressure range (or 7,000 psi arbitrary figure), by logic you will no longer achieve 2.5 Deq velocity.

Peak or Max pressure does not determine the velocity of a load. If for instance you load Red Dot & Unique both to give 1 1/8oz of shot 1200fps (3 DE) velocity your peak pressure will not be the same. The "Work" performed will be the same but it will be applied over a different "Curve". There is much more involved than just peak pressure. One large difference between BP & smokeless is their burning characteristics. BP burns at essentially the same rate regardless of external characteristics. This is not true of smokeless. While certainly common sense & caution need to be used, one is simply not going to run into problems as quick from an overload with black, nor are failures as apt to occur from "Underloads" as with smokeless. Except for the fouling BP is a handloaders dream.
Propellant type BP's burning rate is determined only by its granulation size. Smokeless burn rate is controlled by grain size, shape, configuration, as well as deterrant coatings etc & is made in a far wider range than is BP. In rifles BP is considered a "Fast" powder, in shotguns a compartively "Slow" powder. Many smokeless powders loaded to give comparative max pressure to black simply will not burn dependably under all temperture conditions. They are designed for specific purposes & trouble often lurks for those who try to use them outside their design.

I hope I'm not to sounding too stupid asking this but what are the acceptable pressure levels for a 16 and 20 ga damascus guns? Also what smokeless powders are best used for those pressures?

Jack K

Thank-you Miller. I'd hoped you would come along. That post of yours should be permanently displayed in the FAQ section.

I know Mr. Bell's testing and writing is a valuable contribution to our hobby, but I'm reminded of an old saying about data in general - "There's always someone ready to come along and misinterpret your data, fake it, or apply it to his own pet theory".

Disclaimers and cautions not withstanding, such articles may serve to embolden some really unqualified experimenters who read way more into these test results than is there.

I shot a Bobwhite yesterday with the damascus barreled double hammergun (Imman Meffert):




I shot several Bobs with this damascus single barreled hammergun a few days ago: