Warning
This posts lists data for a powder and bullet combination for which no published data could be found. Published data was used while replacing several key components like primer and bullet. Do not use this data. This data is for my own use and conversation within the forum. Neither TFL or myself will be responsible for the use of the data in this thread.
Decided to try Alliant Power Pro Varmint in my .308 Win today. Lapua Palma cases, CCI 450 primer, Hornady 165 grain BTSP. The only data I could find for this powder, cartridge and bullet was from Federal premium load data. The bullet they used was the 165 grain Trophy Bonded Tipped.
I used a starting load in the middle of the published range at 42 grains. I also loaded in half grain increments up to 44.5 grains, which was .2 grains below the listed maximum charge. Bullets were seated to the canelure.
My lowest charge weight showed approximately a one second delay in firing after the firing pin dropped. I fired four of these to make sure it was not a fluke. The fourth shot did not go off at all. No high pressure signs at all and velocity was 150 fps below published data. So, I skipped right to my maximum charge. At 44.5 grains, only 40% of cartridges had a noticeable delay in firing. Although, the delay was much shorter, only a fraction of a second. I fired the rest of the max charge to empty the brass.
I am left with wondering if I need more powder to make this powder work in cold temperatures, large rifle primers, or to abandon this powder all together for the 308.