Powder weighing problem?

[emmagator]

Ok berger has a max load of RL19 of 60gr at 3012 fps. With all variable considered what would the max variance in fps that i could possibly see with the same load.

 

[Bart B]

If your barrel's bore/groove diameters are larger than what the test barrel used in developing your load data, that same load in your barrel will shoot bullets slower; often much slower. The opposite's the case if your barrel's tighter than the test one.

And if you ever chronograph your loads then let a buddy shoot them in your rifle, he may get up to 100 fps more or less velocity than you do as it's held atop a bench. It's all on how hard one pulls the rifle back into their shoulder.

I personally don't think folks should be so concerned about getting their bullets to the target as fast as possible. I think it's more important to have them all arrive pretty close to the same place. Few, if any of us will ever see the difference afield down range if a bullet arrives a tiny bit slower, or faster.

 

[emmagator]

Ok, another question. What would be considered a minimum acceptable velocity for a long rang rifle in a 270wsm cal.? I would eventually like to try this rifle out to 1000yrds for fun.

 

[Kevin Thomas]

Take a look at the BCs of the bullets you're considering, and run them out on a ballistics program. Those that are anywhere near (say +75 fps or so) to the transonic region should get bumped from the list. Working backwards, that will also give you a range of MVs that you can consider minimum for this application.

Terminal performance is another matter, and just because a given bullet will stay supersonic at this distance, doesn't necessarily mean that it'll be a good hunting bullet. Ask around a bit on that one, and see if there's any good evidence to support the bullet you're considering.