You're an extremely lucky guy. There are enough guys out there who have used Bertram brass and was totally dis-satisfied with the product. Dimensions can be off, rims can be too thick or thin, neck splitting after only one load, brass not fitting the chamber after re-sizing, etc. My experience with Bertram brass was not too good to say the least. I got some brass for a 475 Jeffery's No.2 for my partner's dad to do some reloading as his supply of Kynoch ammo was exhausted. I encountered overly thick rims and have had the brass not fit the chamber after re-sizing. I had to beg some other dealer for some BELL brass and the problem was solved. But then again, I've heard of some who have had problems with BeLL brass also. It's a coin toss as to when your turn is up for shit happening to you.