I think 8,000 psi is a good max for these old guns in 10 and 12 gauges.






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I'll have to measure it when I get home. And the answer to that question is to shoot geese. We have the 14 to 18lb greater Canada geese that most people down south don't get to see as they stay up here all winter. The black powder is not burning well at -20°C so I want to know what was the safe pressure these old guns work at?

Ok thanks. Just saw your last post.

There are a few members in southeast New Hampshire who are really into their short tens and all sorts of waterfowl. They mostly load their own ammo and really know what they’re doing and can give you advice you can take to the bank. I’m certainly no authority on this but they are. Pete Lester, Scott Kittredge, Frank Cronin, Bill Janelle... can one of you come on and help this member?





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If black powder is doing poorly at -20 C, I would think that some low-pressure smokeless loads might also do poorly...

Primer selection may also be important in extremely cold weather.





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I use longshot powder in the cold weather in my modern 10 ga shotguns. I have some load recepies for 2 7/8" shells that use it however the pressure is around 9000psi

You are the first to claim BP doesn't work well in cold weather. Years back when I was a died in the wool muzzle loader, I did a weekend rendezvous and it was -30F with a wind chill of a -70F on Saturday - the shoot day. No one complained of guns not going off or poor performance. I froze my behind off and it was the last winter shoot I did. Maybe it was your primers - I'd try Federals at the least, or maybe the ones made for BP - if they really are different. On another thought, I have about 50 DGJs, and reread them. I just read one of Sherman Bells articles about using nitro and BP to see how they compared to each other.. He measured pressures at 1, 3, 6, 9, and 12" down the barrel. He kept pressure down to BP pressure - 5500psi or less. He tried Blue Dot, 7625, and Clays keeping the velocity at 1250fps or less. Pressures were so close you could say they were the same. His favorite duck load was a 1 1/8oz of Bismuth, 16grs of PSB buffer, a Lage Uniwad and 24.5grs of 7625 in a Win hull and primer. #4 or 5s for ducks, #2s for geese. He had 1100fps and 5500psi one inch out from the breech. Maybe you could find some 7625 or send some of your shells in for testing. Precision Reloading does it. Good luck. Or just stoke it up with smoke.

Ya I sure would like some 7625. Do you know if they still make it? Because all the supply chain is telling me that it's a Dinosaur dead and gone but not forgotten lol.

For starters let me say that -20C is -4 F, you will find me at home these days in weather like that. When IMR 7625 was discontinued I settled on two bismuth loads for waterfowling, 1 1/4 ounce with 24 gr of Green Dot and 1 3/8 ounce with 24 grains of Unique. These loads have been tested with Remington hulls and Winchester primers with 9000 and 8800 psi respectively. I have had no problems with them in a variety of composite barrel 10's, Parker NH, Rem 1894, and two Lefevers. Again as others have told you every gun is different but I believe 9000 psi is safe in my guns given their barrels. These two loads are in the spreadsheet you can find in another thread. I believe if you use these loads in a Federal hull, which I often do, the pressure will be lower due to the fiber base wad. If you use Remington hulls be advised there are different styles, the emerald green ones have less room and can't be loaded with a fold crimp as you see in the recipe. I solved that problem by using a rolled crimp.