I worked up 50 loads for my XDm40 yesterday. Actually it was the first time I shot it. Ran 50 Win 180 factory loads through it first. Fun gun to shoot!
Anyway, I used AA#7 w/ 7.8gr and 8.0gr and 180 Berry's. The 7.8gr were more accurate and ran about 910fps. The 8.0gr ran higher and to the right. I did have a couple flyer w/ each load and was wondering about the crimp. Since it's a plated bullet, should I be crimping as lightly as possible due to the fact that it probably causes an indentation in the bullet? I am using a Lee die set, which I really like. Seems like good quality and easy to set up (no Allen set screws!), also didn't realize that they are made about 20 miles from my house! The Lee crimping die re-sized on the up and down stroke along with crimping. Does the resizing crimp a little? Enough?
Also was wondering do guys generally site in a gun by load creation? I have some mobility left to right on the XDm, but not up and down. I'd like to get a little more speed out of it, not necessarily for the Berry's but for protection loads.
Also noticed a discrepancy in the loading data for AA#7 in the books. The Lee load sheet w/ the dies and Accurate site recommends 7.7 to 8.5 and the Speer manual recommends 8.7 to 9.7 for similar FMJ 180gr bullets!!! The other powders have differences, but not like that...
Good job on the first loads!! Fun huh!!!
Crimping for an auto caliber is a bit different then for a revolver caliber. The auto uses a taper crimp. Where the revolver uses a roll crimp. The roll crimp is generally a stronger crimp as it will roll the lip of the brass case into the bullets cannalure. On the taper crimp, you need to keep the rim exposed so that the cartridge head-spaces properly in the chamber. You can tighten up a taper crimp, but not as much as you can with a roll. Generally a very tite crimp is not necessary.
Yes you can keep adjusting the load to find one that prints to the point of aim. Its how it was done many moons ago, before adjustable sites. With fixed sites on revolvers, you used to just bend the barrels!!!
Something to remember: Heavier bullets will print HIGHER, than lite speedy bullets. Differences in loading data between manufactures is very common. As many variables exist. Temperature, altitude, barrel length, action, primers, cases, and powder lots all make differences and account for the majority of these variances.
CW
