Quote History Originally Posted By 4x4junk:
Shot some of my bullets today with 700x, same problem. 2 ft group at 20yds and keyholing.
Shot some today with hp-38 and 700x with my friend's bullets, same mold and sizing die I believe, different lead. They shot 2 inch groups. We checked the hardness of my bullets and it is 10 BHN. Have we found the problem? I understand they should be 14-15.
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Possibly, but maybe not in the way that you think. A 10BHN bullet will absolutely handle 9mm pressures no problem. A much more common problem that is more pronounced with soft bullets is having your brass sizing your bullets down. Even with a case expander, the neck tension may be too great for the bullet you are using. The test for this is simple, pull a few bullets from loaded rounds and measure the diameter. If they are smaller than when you loaded them, that is your problem. It's probably your brass, but another possible source of this can be something like a Lee carbide crimp die, which has a resizing ring inside of it.
It is also possible you are shooting less than ideal bullets. If you are getting bullets with wrinkles and other imperfections in them, that will at the very least be an imbalance, and possibly allow gas cutting. It doesn't matter what coating you use, once the bore is fouled, its never going to shoot good.
#1 pull some bullets, check their diameter.
#2 make sure your bullets are at the very least fully filled out before coating.