What's up with this?

[crabo]

I ordered some bullets from Montanna Bullet Works. They are the RCBS 82032 and weigh 155 grains or so, and the mold is marked 158 grain.

However when I go to Midway

http://www.midwayusa.com/eproductpage.exe/showproduct?saleitemid=436963

the mold is listed as a 150 grain swc.

Montanna told me the mold is marked with the number and the weight. I like this bullet. I want to get the same mold. Is this one of those things that the mold companies sometimes change the mold?

Do I need to order the mold and see if this bullet will fit that mold and return it if it doesn't fit? Or do I need to contact RCBS?

Thanks,

Crabo

[Buckshot]

.................Mould makers stipulate the weight with a certain alloy. More antimony & tin = lighter boolit. Less of those means more lead = heavier slug. And yes the design may vary a bit from cherry to cherry so there is some variations there. If the photo looks like what you're using, and the company you bought them from says that's the mould, then it probably is the same number/design.

The first example of such that I know of personally is the Lyman 147gr FNBB slug for the 9mm type pistols. Cast from some reasonably hard alloy they weigh 153grs. That's 6 grains more then 'spec'. That 6 grs is about 4% difference. The variation in weights for that RCBS is very close to 4% also.

..............Buckshot