Both my SP-01 and P-10F had properly cut chambers, but short cut leades. 147gr blue bullets loaded longer than 1.132" wouldn't pass the plunk test. Longer rounds would get stuck on the rifling and lock up the gun. I deepened the lead with a Clymer .35 throating reamer. I secured the barrel vertically in a vise, cleaned out the chamber/bore, and lubed up the chamber and reamer with Rapid-Tap. I slid the reamer straight in until it touched the rifling, then began slowly turning with zero downward pressure. I could feel the blades sort of "step" between the rifling grooves, so I'd pull the reamer straight out every 2-3 "steps", clean everything, plunk test with a round loaded to 1.140", then repeat. In total it took less than 2 full turns. The nitrided barrels are murder on HSS. Mine were pretty dinged up after doing my P-10F.