It's late at night and my back is killing me. I thought some of you might like to read about a test I ran back in 1980 with regards to cold weather and its effect on ammo performance. I had read an article about polar bear hunting with Fred Bear the archer and his backup gun hunter. Earlier in his carrier Bear swore that he never had a gun backup. In time he softened and admitted to having a rifleman off camera. In the article I read in the late 70s the two men were talking about how the cold might effect the primer and powder in the rifleman's .375 H&H. Temps where they were hovered around -20 to -40 degrees F. I have forgotten what they concluded, but it got me interested in setting up my own experiment with a 7.5" .44 Mag SuperBlackhawk. I had a 240gr cast SWC load that used 22.0 of Hercules 2400. This was before Alliant bought them out. That load was the standard of the day. It gave me a very accurate 1387fps on average when fired during the summer months when the silhoutte season was on. I would say the average temperature was around 75-80 degrees when I chronoed them. I have always kept reloading info from the very start of my reloading as a teenager. All the numbers here are taken from notes written back in 1980.
So I had a good bear load when the air temp was normalish for humans. I wanted to see what could happen up in Alaska if a bear became a problem in really cold weather. Into the freezer chest went the fully loaded Super Blackhawk. I let it sit over night at a temperature of -24 F, and in the morning before the outside air had a chance to get too warm, I wisked the revolver out the back door and shot all 6 rounds through my chrono that had been set up and recorded the following speeds: Shots one through six - 1211,1237,1248,1231,1275,1266fps. That's an average of 1245fps which is a reduction of 142fps from the warm gun, warm air 1387fps average. A little unscientific, but fun for a young 23 year old trying to learn something.
I think a bear shot between the running lights with a 240gr LSWC at the reduced speed of 1245fps wouldn't complain too much about the difference. I have stopped worrying about tracking down wounded Polar Bears with my .44 in the dark Artic night.
Hope you found this interesting.
SA John
P.S. I had to detail strip the damn gun after because of the tremendous amount of condensation that fairly poured out of the gun's innards as it warmed up. I had to get all the water out, it was a blue-steel gun. I won't repeat that experiment again with a blue gun.
So I had a good bear load when the air temp was normalish for humans. I wanted to see what could happen up in Alaska if a bear became a problem in really cold weather. Into the freezer chest went the fully loaded Super Blackhawk. I let it sit over night at a temperature of -24 F, and in the morning before the outside air had a chance to get too warm, I wisked the revolver out the back door and shot all 6 rounds through my chrono that had been set up and recorded the following speeds: Shots one through six - 1211,1237,1248,1231,1275,1266fps. That's an average of 1245fps which is a reduction of 142fps from the warm gun, warm air 1387fps average. A little unscientific, but fun for a young 23 year old trying to learn something.
I think a bear shot between the running lights with a 240gr LSWC at the reduced speed of 1245fps wouldn't complain too much about the difference. I have stopped worrying about tracking down wounded Polar Bears with my .44 in the dark Artic night.
Hope you found this interesting.
SA John
P.S. I had to detail strip the damn gun after because of the tremendous amount of condensation that fairly poured out of the gun's innards as it warmed up. I had to get all the water out, it was a blue-steel gun. I won't repeat that experiment again with a blue gun.