I am looking at buying 100 cases of cylindrical to form into .500 A-Sq.

I need to know the uniformity and quality.

Thanks.

I have a 43 Mauser. I use Mast (Bell) brass. I have seen Bertram brass in the same caliber and the difference is like night and day. Bertram might be fine as far as form, fit, and function goes, but it sure doesn't look like the best stuff to me .

I've had experiences with Mast brass in 404 Jeffery and 7.82 Warbird, the Lazzeroni brass. It's pure GARBAGE.

I just received 20 cases of Lazzeroni brass at slightly over $40. In those cases the brass had a weight spread from 266.9g to 276.0g. Not any two pieces weighed the same. The wall thickness varied minimum .006". Compared to another lot of their brass it was obvious it could not be mixed. The other lot was equally as disparate but it weighed 50g more, in the range of 318g to 330g.

The Jeffery brass I tried to use to form a shorter fat cartridge, a Jamison. The neck of the new brass was in the body of the Jeffery cases. The thickness varied there from as small as .009" to .027". In spite of annealing at various stages in the forming process, the necks split within 5 reloads and many on the first or second firing. In contrast, forming the same case from RWS brass there was never a neck split and some of the RWS cases are still going at over 20 reloads.

Mast brass has been pure junk for me. Except for the fact they supply odd unavailable cases their brass couldn't compete with any other. In some cartridges you have no other choice and that's the only reason they are still in business.

Ditto Bob338. I have used MAST brass in Dakota with similar problems. I use a lot of MAST brass in the Dakota case design. Some of it is great and some is pure crap. I have had to cull 30%+ because of concentricity issues and inconsistent neck thickness. After trimming, case weight was all over the place. MAST uses a thicker web and base which is a good thing, but something is definitely not right with their manufacturing process from lot to lot.

If you get their good stuff, it is great. If you get their bad stuff, it is Remington.

Thank you for your replies, you saved me money.