I'm having "issues" with reloading specifically Hornady .458 - 500grs in both the Lott and Win Mag.

Cases chamber perfectly prior to bullet seating after the expanding die - RCBS dies.

After bullet seating it appears the area of the case near the rear of the bullet has increased just enough to prevent chambering. It doesn't appear the bullet is off center as happened in the past with Hornady dies.

Cases are trimed to length, chamfered / deburred, and both bullet and case are lubed w/ RCBS sizing lube. Alternate crimping weight / Lee factory crimp die doesn't change inability to chamber.

Current brass is twice fired Hornady, but a new bag of Winchester and some Imperial sizing wax is on the way.

Any ideas?

Very odd, seems you have tight chambers or tool marks/burrs causing this problem. Can't say I have any problems with my Remington 798 .458WM using Hornady 500gr bullets. Are these factory rifles, or have you had your rifles re-chambered to these calibers?

Are those Hornady #4504s? I load them in my Lott and Weatherby without any problems. Have had the off center problem you mentioned with lead bullets and Hornady dies with the Lott though. The only other thing I can think of is are you crimping them? Too heavy of a crimp might cause that problem.

mwm464: I have been reloading Hornady 500 grain DGS #4507's in my Sauer Hatari in .458 Lott. I've also been using RCBS dies and Hornady Brass. Like you, I also use a Lee Factory Crimp Die. So far, I have experienced no chambering problems. Have you tried the Hornady Factory rounds to see if you experience the same problem?

I'm reloading for a new Win Model 70 Cabelas Anniversary Special. The barrel shows copper, so the factory has test fired her prior to shipping. I just received new winchester cases and Imperial sizing wax, and will attempt to get a few together in the next few days. Hopefully a range report on monday...

You might be collapsing the shoulder.

Does the shoulder look like these?



Are you crimping at the same time you are seating?

George

quote:

You might be collapsing the shoulder.

No shoulder on either caliber.

Geronimo

Back the seating die off. I think you're crimping as the bullet is seated.