I did a test a few months ago. I made up all GFL cases and weighed all the load on my scale. Then I used some DEWC TEK coated bullets. With 3.8 gr of 231 powder I found the ones crimped at the end of the bullet to be on average 65 fps faster than the ones crimped at the crimp groove that is about 1/8 inch from the end. I did it again using CFE Pistol powder 3.8 gr. The ones crimped at end were about 50 fps faster than the crimped at groove. I didn't weigh each load on those. I let the powder measure handle it.