I had 7625 become completely ineffective at duck swamp temps (20's) in a 1¼oz load @ about 7K psi. It propelled the shot hard enough to hit the duck (Mallard) but not enough to kill it. This using #5 lead in the pre-ban days. After my son finished it off with a 20ga using 1oz of 6's we checked it out & those 5's had hardly broken through the skin. Both my gun & shells had stayed in the house & were transported in the cab of pick-up with heater on, those first two shots were fired within 30 mins which was sufficient time to kill their performance. Some shells from the same identical batch had been used previously on some early season squirells in tall hickories & proved powerful & effective, but at higher temps. I forevermore swore off of 7625 for cold weather use, unless in full power loads for which it was designed, so have no idea if any change has occured to it over the years or not. "IF" you insist on using so light a load of 7625 for use where the temps may drop below freezing I would at least change to a hotter primer as the Fed 209A, I was using the mild CCI on my loads (To Keep pressure down).
