I recently tried using 37 grain Calhoon DHP bullets in my custom Ruger 77/22 in 22 K-Hornet. I loaded 5 rounds each with Lil'Gun powder using 12 grains; 12.5 and 13 grains. Rather than starting with the 12 grain loads, I inadvertently started with the 13 grain loads. My once fired case separated on the first firing. The head came out when I ejected the case but the remainder of the case stayed in the chamber. The case was easy to remove. I cleaned the rifle. Then fired the 12 grain loads with no problem or any signs of high pressure. I have previously loaded 40 grain Hornady BT bullets with 13.5 grains of Lil'Gun with no high pressure signs. Does anyone have loading info for the Calhoon DHP bullets? I purchased 1,000 bullets. The 12 grain load shot approximately .78" but I did not have my chronograph with me so I don't know the velocity.