RR44 wrote:I am only new to the 450 bm not to reloading, I have bee reloading for over 25 years now, I know different bullet weights but I've never used a different diameter bullet in the same gun
The bore of the 450b straddles the two worlds of .451 and .452. Having reloaded my share of both, they're pretty much a horse apiece. That having been said, there are IMHO, better choices of the represented types of bullets out there in .452 than .451, but the discerning differences are mainly realized in a BR environment. For hunting and entertainment target shooting, either is a good choice. I too had around 25 years of reloading mainly bottleneck rifle calibers, but also common straight-walled pistol calibers, before getting into the 450b. If you produce good results in other rifle (bottleneck) calibers, you will produce good results with the 450b. Very similar to the 460S&W. IMHO, if you shot the 460S&W out of the same rifle, I suspect you would have trouble telling the results apart from one another.
The 800 pound gorilla in the room is neck tension. Good reloading prep of your cases, as you would with bottleneck reloading, yields good results in this straight-walled caliber as well. Consistent case prep and crimps regardless of which you choose, will yield quality, precision loads. Less attention to fine points and you still produce good loads. It's more forgiving than most will let on. Quality control by the bullet manufacturers is not as tight as one might guess, when they get up to this size. I've mic'd bullets as small as .449 being sold as .451 caliber. Luckily most will be in the range of .451-.452. When you factor in the percentage of overall diameter that represents, it's within the same variation you will find when you mic .308 or .243 bullets.
Have fun...
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