Been working on load development for a 6.5mm Swedish Mauser using the Lee 170gr cruise missile, which is fairly long at 1.25". In experimenting with COL and press setup, I've been assembling dummy rounds and taking them apart using an impact bullet puller. For the most part I've been using the same bullet over and over. Well, yesterday when using the impact hammer the bullet broke in half with half of it staying in the brass. The bullets are at BHN 13, but the alloy is a mystery since I make it up from what I get from a recycler where I can pick through their bins which include a variety of alloys.
I'm trying to figure out if the alloy is too brittle or if this is something that could happen in the normal course of subjecting a bullet to more than it's fair share of stress in an impact hammer? It usually doesn't take more than two or three whacks to dislodge the bullet, so I'm thinking that isn't that stressful. If the bullets are too brittle, I wonder what effect that is having on accuracy. The cross section of the broken bullet is crystalline; the bullets are water quenched.
Any thoughts on this would be appreciated.