Bob58
12-04-2007, 01:44 PM
Thanks to all who responded to my request for help with the "bullet jumping crimp" problem in my two .44 Mag 629-4 revolvers. I wanted to let you know what has occurred to fix the problem.
I think at least two posters suggested that my Dillon RL550 powder die, which bells the mouth of the case, was expanding the case too much, thereby decreasing the "grip" that the case had on the bullet. It didn’t even occur to me that this might be happening. Consequently, I tried inserting the expander part of the die, by hand, into a case that had just been sized. It was way too tight to go into the case, showing that the suggested expansion was in fact taking place.
So, I placed the expander part of the die into the 4 jaw chuck in my little 6" lathe, and removed enough of the metal (too hard for a file - had to use stones, finishing with emery paper) so that a case would fit over the expander without expanding the case body, only belling the mouth.
Rounds now loaded using the modified expander die, belling the mouth without expanding the case, were not growing in length more than a few thousandths for the last round fired out of the 6 rounds in the cylinder. I think the problem is solved, although I’m going to shoot several cylinders full of these, prior to taking them hog hunting, just to make sure.
Again, thanks to all who responded. Sorry it took so long to report back - jury duty, combined with too little light in the evening to do anything, plus a weekend out of town for a wedding took away too much time from the "important" activities of load development / troubleshooting.
Bob58
I think at least two posters suggested that my Dillon RL550 powder die, which bells the mouth of the case, was expanding the case too much, thereby decreasing the "grip" that the case had on the bullet. It didn’t even occur to me that this might be happening. Consequently, I tried inserting the expander part of the die, by hand, into a case that had just been sized. It was way too tight to go into the case, showing that the suggested expansion was in fact taking place.
So, I placed the expander part of the die into the 4 jaw chuck in my little 6" lathe, and removed enough of the metal (too hard for a file - had to use stones, finishing with emery paper) so that a case would fit over the expander without expanding the case body, only belling the mouth.
Rounds now loaded using the modified expander die, belling the mouth without expanding the case, were not growing in length more than a few thousandths for the last round fired out of the 6 rounds in the cylinder. I think the problem is solved, although I’m going to shoot several cylinders full of these, prior to taking them hog hunting, just to make sure.
Again, thanks to all who responded. Sorry it took so long to report back - jury duty, combined with too little light in the evening to do anything, plus a weekend out of town for a wedding took away too much time from the "important" activities of load development / troubleshooting.
Bob58