I have seen on Northforks website that they do not have the BC for their bullets. My questions is how to calculate bullet drop to set up a TDS scope? I do not have access to more than a 100 yd range.

thanks,

I am not familiar with the TDS reticle so take this with a grain of salt. Unless you are shooting beyond 300 yards, the BC shouldn't make much difference. A 220 grain roundnose 30 cal bullet at 2500 fps is 2.5" high at 100 and 11" low at 300. That's not much different than the 180 grain at 2700-2800 fps, which is about 2" high at 100 and 8" low at 300. Unless you are shooting something really small, the extra 1/2" shouldn't make any difference. At 300 yards you'd be holding over any way, so just hold over a smidge more.

Of course, for the precise among us that is no good. So I would suggest that you might be able to approximate the BC by comparing the bullet to one with a known BC. I.e. the XXX Northfork looks like a Nosler YYY, which has a BC of .ZZZ.

But again, if you aren't shooting beyond 300 yards, it probably doesn't matter. And if you are shooting beyond that distance you might be better off with a spitzer shaped bullet anyway.

LWD

Here is a good explanation of what you'll need to do: http://www.prbullet.com/bal.htm
http://www.loadammo.com/product/bc-calcs.htm You will obviously need a chronograph.
LWD has it right though. Too many hunters get all jacked up about BC when they are only shooting out to 300yds or so. Check out drop tables, there just isn't that much diff. when you are talking big game bullets out to even 400yds. I've found matching the NF w/ a bullet of sim. design & using that BC gets you pretty close, within just a couple of inches out to 400yds. For me, that's far enough.

if you're using northforks bullets you're probably using them on big game. big game doesn't know anything about BC, SD or the other BS.

quote:

But again, if you aren't shooting beyond 300 yards, it probably doesn't matter.

a) Low BC with low velocity = more appropriate for short to medium range

b) Higher BC with higher velocity = more appropriate for medium to long range

Where we draw the line depends on zero-in distance and accurate range estimation. If the velocity is the same and there is a small difference in BC, then it is not so much of a problem - just know your trajectory.

Warrior

quote:

Originally posted by tradewinds:
...My questions is how to calculate bullet drop to set up a TDS scope? I do not have access to more than a 100 yd range. ...

Hey Tradewinds, I agree it is very possible to take one of the Bullets, lay it on a bullet that looks like it in the Speer Manual and you will be "relatively" close to knowing the BC. That is the Good News.

The Bad News is that you really need to shoot the Bullets, in your firearm, with your exact Load, at the actual distances you intend to take shots at Game, and then make an Accurate Drop Chart. The computer generated Drop Tables can help you get onto the paper, but they are just not always accurate enough to take a shot at Game beyond where you have practiced.

People can site as many examples of how close they are, but it doesn't matter. There is a lot more to shooting at Distance than having a "Guessed At" Drop Rate.

You just need to find a longer Range and get on with it.

Best of luck to you.

Absolutely +1 to Hot Core.

The very last thing a guy who only has access to a 100 yd range should buy is one of those reticles. You absolutely owe it to the animal to practice at the ranges you will shoot out to.

quote:

Originally posted by kraky:
Absolutely +1 to Hot Core.

The very last thing a guy who only has access to a 100 yd range should buy is one of those reticles. You absolutely owe it to the animal to practice at the ranges you will shoot out to.

+2