-- Cold weather really does affect velocity! I have a 9.3x62 that normally shoots 286-grain Norma Alaskan bullets loaded with Re. 15, at around 2300 fps. Yesterday at the range, with the tempature around 38 degree, it barely broke 2200! Accuracy seemed a little off also.

-- Odd how brass from different manufactuers reacts differently to sizing. I reloaded 20, once-fired, 8x57 cases made by Winchester the other day with Hornady 195-grain bullets. Then I reloaded 20 Sellier and Bellot cases with the same bullet. On the Winchester loads, the seated bullet fit snug when pushed into the cannelure without crimping, however in the S&B loads, the bullet moved freely back and forth in the cannelure, requiring a crimp to freeze them in place. Not a big deal, as both loads, with the same charge of IMR 4064, shot to the same POI at 100 yards. I just wonder what the difference is (difference metallurgy, I guess).

-- Not reloading, but we were shooting a bunch of milsurps with different ammo and discovered that 180-grain Privi Partizan, .303 British, only chronoed at around 2200 fps., while 180-grain Winchester factory loads spit'em out at 2450. I thought this odd, since European stuff is usually hotter than American ammo in milsurp calibers. On the other hand, Privi Partizan 7.62x54R spit out 180-grain bullets at close to 2700 fps out of a M-44 Nagant carbine! That's smokin' hot! And for the record, it shot great -- up to 50 yards, that is. At 100, you would be hard pressed to hit a human at any point on the torso. We also shot a k31 Swiss with GP-11 military ammo. Of course it did what all Swiss guns and ammo do -- shot 2" open sight groups all day long. No wonder the Nazis didn't attack Switzerland in WW II!

Ramblings over. Have a nice day.

Yup! but my 1/2 MOA 40 degree loads are still within that 1 MOA margin at 75 degrees providing the accuracy for the hunting condition rather than at the summer range.

I shot a velocity/pressure test the other day with cartridges loaded in 1 grain increments. It was under 40 degrees outside. I had the shells in my truck where it was warm. It was interesting to note how velocity acted the longer the shells were out in the cold. Velocity went up as expected with increased charge til a certain point then began to fall and I'm sure it was because the higher charge weight shells got fired later and had time to get colder as time went on.