Double tap

I bought a box of D.T. for the first time ever a few weeks ago it's 454 so that's probably why it jumped crimp. Or they just did not crimp it well enough. To my knowledge all 454 casull cases should have a pretty heavy crimp right? Because of the heavier recoil.

I appreciate the feed back

Bullet pull is basically the recoil acting like a commercial inertia bullet puller. Each shot is a whack toward loosening that bullet. I found in my .429 GNR and seating in the lowest crimp groove on the Lee 310 gr. FNGC (to get 2 more grains of H110 and 50 fps) byt the 5th shot that #6 round is starting to pull some, but the long Ruger RH cylinder, it's OK. Just don't reload and keep banging on that pounded round. It will eventually pull enough to lock up the gun.

As a sacrifice to performance the .429 GNR does not have all that much case neck to hold the bullet with tension. I've always thought neck tension is paramount for holding the bullet in place, more so than a crimp in my opinion. You know that going in. On the .429 also if you try to crimp too much, get too crazy, it will sort of iron out the tension in the neck. I remember modifying my Hornady crimper and experimenting. The finding was to keep as much neck tension as possible, loading it more like a rifle round, and minimal roll crimp on the short neck. OF course if I used the front crimp groove on that bullet I lowered 2 grains charge, let 50 fps go, and had no concerns at all with pull. Probably a smarter way to go anyway, 1550 fps with a 310 gr. bullet is plenty.

Experimenting with powerful cap & ball it was a nightmare. The 340 gr. load at 750-800 fps only lasted 3 shots before number 4 would slide out of the cylinder and lock it up. How in the world can you hold a bullet in a cylinder shooting a 275gr. greased bullet, shoved down the cylinder front, at 900 fps in a 3 lb revolver. It too by the 6th shot was getting close to locking up the works. It ended up being a compromise with bullet weight and velocity. The 250 gr. at 1000 was the best mix of power, speed, and recoil. That's why so many shoot a tiny round ball at high velocity (1200 fps). It's more worry free, but sadly restricted in power.

On a .454 for instance, you shoot two, reload, shoot three, reload, shoot four! That poor 5th round is bound to be pounded ( 9 times) unless it's literally glued in place.

If Heavy Duty .44 Magnum loads would stay put. As I recall no rounds whether jacketed or cast could survive two cylinders full without jumping the crimp.