I read an article a few months back in hand loader magazine, They suggested that gas checked bullets could significantly increases pressure. I tested 15 each, checked and unchecked, Lyman 358156 bullets cast out of wheel weights and lyno-type mix, heat treated to a BHN of 28. All components new Win, brass Win, primers the powder load Mid, range in all 30 rounds I shot them out of a 357 Dan Wesson. 6 inch barrel. I Cleaned the barrel between checked and unchecked rounds. Chronographs of rounds fired average was 1014.5 FPS. With the checked bullets traveling. An average of 15 FPS faster. Has anyone else tested this, with a different bullet , Hardness of bullet or caliber, and what results did you get. I’m suspicious of the hardness of the unchecked Bullets. As to with the BHN of 28 did the unchecked bullets seal properly..