Toby Bridges of the North American Muzzleloading Association is an expert on blackpowder rifles and loads. Here is some new info from Toby that will help you sight-in, shoot and hunt better:
“Temperature is one variable that affects muzzleloader performance. So are changes in the humidity and elevation. I almost always obtain the best and most consistent accuracy with saboted bullets when shooting at temperatures from about 40 to 60 degrees. Here in Montana, I’m lucky that through most of June I can still get in several hours of shooting early in the morning with temperatures still in the upper 40s and into the 50s.
Even in early July, I can drive up to 5,000 or so feet and shoot for a couple of hours before temperatures break into the 60s. Up there, I have noticed how another 2,000-plus feet of additional elevation tends to make the rifles and loads I shoot print a little higher than down at 3,000 feet where my personal shooting range is located.
Most days when I shoot, the humidity level is 25-35 percent. However, I often drive out to my range on calm, rainy days when humidity levels are 90-100 percent to check how the increase in air moisture affects my rifles and loads. In higher humidity, the loads print just a bit lower than normal.
Here’s a link to my 2014 “50 Consecutive Shot Test.” Nothing special was done to either of the two rifles I used for the test. Each of them had been shot 300 to 400 times prior to the test session. The loading components (sabots & bullets) were straight out of the packaging, and the charges of Blackhorn 209 were volume-measured right at the range.
Two contributing factors to the accuracy I enjoyed (1.285”): the entire shooting test took place with temperatures ranging from 38 to 56 degrees…and each rifle barrel was allowed to fully cool down before reloading.
I haven’t done much muzzleloader hunting the last couple of years, but I’m planning to this fall. What about you?