Ted;
I tried shorts but the gun I was hunting with, even though it would feed them OK threw a pattern rather than a group. I very quickly went to standard velocity LR's. My reasoning for this was the lack of the sonic crack didn't clear a tree where several squirrels were cutting. They would stop for just a few seconds & then go right back to work. The High Speeds would virtually always clear the tree with the first "SONIC CRACK".
Never had a problem with it leaving them laying on the limp, if properly hit they always fell. Had a few over the years lodge in a fork on the way down, but that is totally irrelevant & could happen with any load one might use.
Totally agreed that very cold weather lowers the performance of any load. However when one is skirting the edge as when using slow burn rate powders at a low pressure it doesn't take as much "Lowering" to produce a total failure. I never had that happen to me when using appropriate powders for the load at reasonable pressures. By "Reasonable" my opinion is no less than 7˝K, black of course being an exception. It would seem to virtually temperature insensitive & burns at essentially the same rate regardless of other conditions.
The load I was using that day I mentioned actually had 1Ľ oz of #5. It was loaded to about 1150 fps @ 7K according to the manual. Case & primer were "Soft" to reach the lower pressure.
It got the shot out the barrel, but with a rather hollow sound & I had to shoot the mallard twice to get him on the water, still swimming. My son finished him off with a 1oz load of 6's from a 20. When we dressed it the #5's were found stuck in the skin, while the 6's had well penetrated. Obviously this was a matter of velocities so low with the 5's they didn't have enough oomph to penetrate. Temps were not below Zero, but just below freezing, in the mid to high 20's. This was in the late 1970's prior to total lead ban. I quit using slow powders at pressures lower than normal & never looked back nave had reason to regret it.
If a gun won't take 8K psi then depending on exactly what it is & what it's other values are, either hang it on the wall, throw it in the dump or resign it strictly to light loads of Black.
