Safe pressure?

[Bill Graham]

Turning to you all because of the multitude of conflicting information I am reading and hearing regarding acceptible pressures for shells in older guns; specifically Sterlingworth 12ga and 20ga. We have a 20ga ejector (1937), and a 12ga extractor (1922). The 12ga has 2 1/2" chambers. The 20ga has a Savage factor re-barrel, and the 12ga is a Philly fluid steel.

One reputable gunsmith who skillfully restores old doubles, and seems to like Fox guns a great deal, said to not exceed 9000. Others have said as long as you limit the gun to low brass, you're fine. What number on the box equates to the pressure of the round, and what is the consensus here among Fox experts as to what is safe as a regular diet in the guns we have?

Thank.

[vaturkey]

What Dewey said. Polywad Vintager shells are another option to consider that will work.

[WPGRIFFON]

A

[Researcher]

Back at the time the Ansley H. Fox shotgun was introduced, the heaviest 12-gauge loads our North American ammunition companies put out was 1 1/4 ounce, which could be had in any of the 2 3/4 inch or longer paper cases. The heaviest powder loads were 3 1/2 drams of bulk smokeless powder or 28-grains of dense smokeless powder such as Infallible or Ballistite. According to some DuPont powder booklets in my collection these loads ranged in pressure from 11,700 pounds to 12,600 pounds, on the high side of the SAAMI specs introduced in the mid-1920s.

Advances in gun powder technology during The Great War, brought us progressive burning smokeless powder shotgun shells beginning around 1922, Western Cartridge Co.'s Super-X loads leading the way. These 1 1/4 ounce payload 12-gauge shells (Western Super-X, Remington Nitro Express, Peters High Velocity, etc.) moved out that shot load at a considerably higher velocity and considerably lower pressures then the old bulk or dense smokeless powders. DuPont claimed 9600 pounds for their DuPont Oval. With the progressive burning smokeless powders our North American ammunition companies upped the maximum 16-gauge payload from 1 ounce to 1 1/8 ounce, the 20-gauge from 7/8 ounce to 1 ounce and eventually the 28-gauge from 5/8 ounce to 3/4 ounce, while at the same time giving them higher velocity. What has 80 years of that done to the heads of our small-bore Fox stocks?!? At least they've fared better then L.C. Smith stocks!!

[FoxintheHenHouse]

Back at the time the Ansley H. Fox shotgun was introduced, the heaviest 12-gauge loads our North American ammunition companies put out was 1 1/4 ounce, which could be had in any of the 2 3/4 inch or longer paper cases. The heaviest powder loads were 3 1/2 drams of bulk smokeless powder or 28-grains of dense smokeless powder such as Infallible or Ballistite. According to some DuPont powder booklets in my collection these loads ranged in pressure from 11,700 pounds to 12,600 pounds, on the high side of the SAAMI specs introduced in the mid-1920s.

Advances in gun powder technology during The Great War, brought us progressive burning smokeless powder shotgun shells beginning around 1922, Western Cartridge Co.'s Super-X loads leading the way. These 1 1/4 ounce payload 12-gauge shells (Western Super-X, Remington Nitro Express, Peters High Velocity, etc.) moved out that shot load at a considerably higher velocity and considerably lower pressures then the old bulk or dense smokeless powders. DuPont claimed 9600 pounds for their DuPont Oval. With the progressive burning smokeless powders our North American ammunition companies upped the maximum 16-gauge payload from 1 ounce to 1 1/8 ounce, the 20-gauge from 7/8 ounce to 1 ounce and eventually the 28-gauge from 5/8 ounce to 3/4 ounce, while at the same time giving them higher velocity. What has 80 years of that done to the heads of our small-bore Fox stocks?!? At least they've fared better then L.C. Smith stocks!!

With what Researcher has said, I would not hesitate to shoot the 2 1/2 dram 1oz 20 gauge shells that I have, in my 1933 Fox. I think we worry so much about something that no one thought about until just in the recent past. I believe the shotguns that we have in our possession now, have for the most part, seen a large mix of ammunition stuffed into them from gun store low brass to 3" magnums over the past 80 years, long before we owned them and started to worry about pressure. Factory made low pressure ammunition available today, wasn't available just a short time ago and only a small fraction of the hunting public reloads, in my opinion.

FoxintheHenHouse

[FoxintheHenHouse]

Dewey wrote:

"There is absolutely no way of knowing what a particular gun has been fed, or how much, over the last 70-80 years."

This is true, but most likely very little of it, if any, was low pressure ammo over most of these years, because it was non existent for the most part and that is the point I'm trying to make.

FoxintheHenHouse

[Knothole]

X

[Mike of the Mountain]

Traditional English game loads were 2 1/2" and 2" 12g loads. Ballistic data can be found on them from BPI. Pressures and velocities lower than our common shotshells made for upland hunting. This year I have used 16g 2 1/2" RST shells to take woodcock with #10 shot. 9 all total ranging from 10 yards to 30 yards. Pheasant and chukar (at least a dozen of each) have been taken with RST 2 1/2" #8 and Fiocchi 2 3/4" #7 1/2 Shooting Dynamics 1180 FPS 1 oz. Also have taken grouse over the past 3 seasons with RST 2 1/2" 20g #7 1/2 and #8 shot. I have also been able to successfully bag pheasant/chukar with 28g Fiocchi Golden Pheasant in #6 and #8 and also using a 3" .410 loaded with #6 or #8. All shot through doubles. Pretty much the same shells I use to shoot Sporting Clays. Clays are ground up and the birds are dead. Majority of the pheasant/chukar kills were all 10-40 yards with a few maybe pushing 45. The .410 kills were all within 30 yards.

[Mike of the Mountain]

Here's a link to a paper on load data and pressures. Very interesting. Not starting a urination contest here, just posting some info. There's a lot more out there than just this paper.

https://docs.google.com/document/d/1F2s ... FU/preview

[WPGRIFFON]

Knot Hole

[Knothole]

X

[Jeff S]

Yikes! Lively discussion. Personally, I love this webpage. Rather than doing endless research on my own, I can wisely take the advice of some really smart people. For several years I shot low brass 2 3/4 shells in my 1918 20 Sterlingworth (and I'm sure the previous owner did also). Then, one day, several experienced Fox owners advised me to buy 2 1/2" low pressure shells from RST. So, that's what I do now. Likewise, last summer when I purchased a 1913 12 ga. "C grade", the seller asked that I restrict my ammo to low pressure RST shells. So, out of respect to him, and the gun, that's what I do. By following the advice of the experienced, I can error on the side of caution and not worry about my beloved guns. Granted, the shells probably cost a couple of bucks more per box (including shipping), but let's be completely honest, if you're using a Fox, money really isn't an issue. As for physics, I remember that mass times velocity equals mass times velocity, but I can't remember anything about pressure. Guys, please keep posting the data. I'm just a business major. Jeff

[Sporrns]

Here's a link to a paper on load data and pressures. Very interesting. Not starting a urination contest here, just posting some info. There's a lot more out there than just this paper.

https://docs.google.com/document/d/1F2s ... FU/preview

Mike, this is quite a piece of work! I'm certain I have seen parts of it before - Can you tell us who the author is and where/how you found it? Thanks, Kevin.

[eightbore]

The compilation has the look of the work of Dr. Drew Hause.

[eightbore]

The two charts comparing black versus smokeless pressures near the end of the post were very interesting. I know we can fabricate loads that approximate black powder pressures, but promotional loads are probably twice black powder pressures.