For anyone looking for 6.5x53R (.256 Mannlicher).
CAUTION: Thin case rims.....
Buffalo Arms is once again back in stock using brass reformed from PPU .303 British. The brass and formed cases are not the issue; however the case rims have been trimmed back to only ~.045” thick on these.

As far as I have ever seen, the “Standard” 6.5x53R/.256 Mannlichr case rims for “vintage” British rifles ought to be ~.060”-.067” thick and the .303 Brit rims are fine as they come from Remington, Winchester, Hornady, PPU.
Buffalo Arms thins the rim to ~.045”, so their cases may have ~ .015”.020” excessive headspace on older rifles unless properly headspaced off the shoulder.

The issue is likely a result of some published dimensions/drawings on Wikipedia, AmmoGuide, and CIP (possibly others) that reference an .049” rim thickness. (When did CIP standards occur?)

This is not a huge issue for guys with single shots or single loaded bolt rifles if the headspace is looked after, however these thin rim cases are a poor fit in the Dutch/Romanian en-block charger clips and tend to jam, that and being simply “not right”.

Buffalo Arms has told me by phone that I can return for a full refund which I will do, but they insist that their dimensions are fine and “they have been selling 6.5x53R cases like this for 25 years, that I am their 1st complaint , and I can just buy Bertram Brass”......so there I guess. Matter settled?

As an aside; properly headstamped Bertram Brass, while much more expensive and often short supply in the USA, is dimensioned as expected for vintage Brit rifles and works quite well.
Too, it is not a terrible amount of work to form ones own brass from .303 British. My choice of Remington .303 British rims work just fine in the Dutch Mannlicher clips and match the dimensions of Bertram.
- Mike

EDITED...... bold face added.....