Yesterday I got out a .17 MK lV that I traded for in Dec. I worked up a powder charge with the bullets jammed into the rifleings. That way I would not have to worry about high presure as I worked with bullet setting depth. Jammed hard into the rifleings I fired 3 shot groups with 20 gr. Hornday`s, 20 gr, Bergers and 22 gr. Calhoons. The C`s were the best with a .545. H`s were .792 and B`s were 1,425. Backed out .010 the C`s were .250, the H`s .712 and the B`s .935. Backed out another .020 the B`s had dropped to .225 with the H`s at .528 and I pulled a shot with the C`s and they went up to .579 with 2 bullets touching. I could not seat the bullets any deeper with the Redding dies I have so no farther test. This gun like a long jump more than any gun I have worked with for a long time, maybe ever. It proved to me, again, that you should always play with the seating depth when going for your best accuracy. I have had guns where it didn`t matter much and others that it was flat critical. With the best shooters it seems to matter more, most of the time.