I looked at data for 140 grain bullets for the 264 and every source that I have for H1000 powder showed a max load of 68 grains including Hornady's manual, except for one manual that I have forgotten which gave a maximum load of 65 grains. I figured that Hornady data would be accurate since it was their powder. (yeah, there I go thinking again) At 65 grains under a Hornady IL 140 flatbase everything looked fine but when I shot a 65.5 grain charge the primers flattened and the FP almost prierced through the cup. The accuracy with the 65 charge was a hair under MOA but I think I will try some boattail bullets and start a couple grains lower with the next batch of test loads. BTW, the chrono showed between 3100 and 3150 with 65 grains.