I recently worked up a deer load for my .458WM.

I'm loading a 405 Remington bullet over 70gr of 3031. I don't have a chrono, but this should be doing about 2150fps out of the 24" barrel. This is an accurate load that will shoot 1-1.25" at 100yds.

My trajectory program says that if I sight to be 3" high at 100yds that the bullets should strike about 3" low at 198yds.

But that is not what I'm getting. I'm 3" high at 100yds and dead on at 200yds. How can this be? My trajectory program says that I would need nearly 2400fps for this to occur. There is no way that 70gr of 3031 could push this bullet that fast . . . is there?

Any ideas?

what's your OAL? i'l plug into quickload late tonight....

I expect your load is quite a bit faster than you tink
jeffe

About 3.25". I don't have the calipers with me, but it's dead on that measurement by the ruler.

I was basing my velocity on the numbers that Ken Waters published some years back.

I've got to get a chrono.

Bob.

Well based off of my experience with two 458s and a chronograph would figure your muzzle velocity between 2280 and 2350 fps with that 70gr IMR3031 load (my rifles shot over 2300 fps BTW).

My QuickLoad says 2263 out of a 24 inch barrel.

And yes everyone needs a Chronograph! Takes all the guess work out of it. Find a cheap Chrony and that will do just fine!

According to data fed into my balistic program using a bullet similar to yours and velocities of 2100, 2200, and 2300fps, none of the loads would zero at 200 and give me +3@100yds. I assumed an unscoped rifle. Please let me know if its scoped and I'll re-run the data. Kudude

Ranger

Why not open the JBM Ballistics program and fiddle with it yourself. Play with the numbers until you get the actual trajectory you have experienced and see what the Velocity says.

Make sure you enter the sight height, temp and altitude. Check the "standard conditions at altitude."

I'm like the others. I think that load is giving you more fps than you realize.

http://www.eskimo.com/~jbm/ballistics/traj_basic/traj_basic.html

Ray

Hi

Lets face it what you see in the field is what you get,its real.
There are so many variables, I use a chrono as a guide and then test in the field after using a ballistics program. However a more accurate test of the trajectory is to shoot at two fixed distances and then use the ballistics calculator to work out the velocity. Norma's internet calculator is good for this.

regards

Mark

I have been using a ballistics program (PointBlank is the name).

Since I don't have a chrono, I load to an expected velocity and check the point of impact at two distances. Then I work back to the velocity.

That is the process that got me to where I am. The program says I should be near 2400fps, but that is way over what Ken Waters got with the same load. I may have a faster rifle than Ken, but apparantly it's not faster than some of the guns you guys have used.

BTW - I do have a 1-4x Leopold on this rifle.

Jeff,

Did your Quickload numbers come up the same as Rusty's (posted above)?

Thanks for any help!

Bob.