new rem 700 300 win mag glass beded ,trigger job redfield
mounts toped with Nikon 4.5x14x40.load Pmc Brass
75.5gn Rl22 horandy 165 fed 215 primer 3150fps.
At100 yards .425 group 2inches high,should be dead on at 200yards ,it's not'' still 2 inches
high 1inch groups. 300 yards 3 inches low.
Now iam not complaning but it's not right and i
can't figure out what the problem is.
It should be 2high at 100 0.0 at 200 -6.77at 300
What's up with this?
Reloaderlen

[ 08-03-2002, 00:46: Message edited by: reloader len ]

How high is your scope above the axis of the bore? The higher it is, the more dramatic the difference in your trajectory (most computer programs assume the scope is 1" above the bore axis).

George

scope is 1 above bore.Ihave another 300 set up the same way ,and it dosen't do this,i shot the
barrel out on it and going to use the action
for a custom job!
reloaderlen

[ 08-03-2002, 02:28: Message edited by: reloader len ]

This is the reason you have to actually shoot your gun at various distances rather than believe ballistics tables.

It looks like you're zeroed for about 250. I'd leave it alone! That's a killer point blank rifle to probably near 350 yards.

Your bullet is still rising after it passes the 100 yard mark, and probably peaks at around 165 yards, and then drops back down to 2 inches high at 200 yards. It continues falling to I'll say a zero of about 250 yards, and ends up the 3 inches low at 300.

The bullet you mention, at the velocity you mention would only be about one inch high at 100 yards for a 200 yard zero, this according to the Nosler trajectory data.

So if you're 2 inches high at 100, your zero is going to be 250 or so.

Ideal zero for that rifle in my opinion.

If you have another rifle which zeros at 200 yards and hits 2 inches high at 100, I'd check the velocity.

Dan Newberry
green 788

[ 08-03-2002, 17:46: Message edited by: green 788 ]

Len,
The thing is that the tables and programs have a nominal drag factor built in to use. The drag factor may be less ( on many newer designed bullets it is much less) on your bullet. This phenominon is seen in a few cases I've personnally shot. The scope mounting issue is also real. And like has been said already, you have to shoot it to know it. It would be interesting to shoot at 50 yard intervals at the same target and labeling each shot. You would then have the trajectory and know exactly what's up!
The Hornady SST, the Swift Scirrocco, and the "plastic tipped" bullets have a much lower drag factor. You should see "flatter" trajectories with these than whats calculated in the program on the PC or in the tables. Many tables are simply reprints of old calculations. The nominal drag factor used more closely represents a more rounded nose bullet than one of the streamlined ones. Nate

len, I have a 7mm Mag that does the same thing with 150gr'rs. It does not do what my ballistic program says it is supposed to do.
I have shot it from different yardages with different weight bullets and recorded the results under my scope lens cover for quick reference.

A little difference is line of sight above the bore makes a big difference in the trajectory. With most rifles, a 40mm scope will be about 1.5" above the bore. Some will be 1.6". If your rifle has a gas escape hole at the chamber, it is usually centered beside the bore and makes a good measuring point. Measure from the center of that hole to the center of the scope. In some of my rifles, there is a scope mount conveniently aligned above the gas escape hole, with split rings that mark the centerline of the scope, making this measurement easy.

If you re-run the ballistics program with the correct measurement, it may answer the question.

Folks, can I respectfully say that we aren't seeing the forest for the trees here?

If you want your bullet to hit 2 inches high at 100 yards and drop to zero (line of sight) at 200 yards, you're going to have to slow that rascal down to somewhere in the neighborhood of 2700 fps.

At 3150 fps, the 165 grain bullet would only be about an inch high at 100 yards. The fact that it is 2 inches high at 100 yards, and again 2 inches high at 200 yards tells me that the scope is zeroed for about 250 yards. The bullet is still rising at the 100 yard point.

Shoot the rifle at a target placed at 165 to 175 yards, and you'll see what I mean. The impact will be about 3 inches high at that range.

Don't mean to be didactic, but it is that simple.

Dan Newberry
green 788

I think another factor working here is the fact that you have a real fine shooting gun that is spitting bullets out without any yaw. If you read the gun rags and the guys are testing bullets with the Oehler system it gives the ballistic coeficent based on the way the bullet "flew" from the end of the barrel to the target. Every once in a while they come up with a really fantastic coefficient that "far surpasses" the bullet manufacturers estimate. I guess what I'm trying to say is a real sleek long bullet that is wobbling all the way to the target is not aerodynamic. But a spitzer that has a super tight spiral (like a brett favre pass) very well could be!!

btw--I just put your data on my quick target program . It said if you are 2.2" high at 100 you will be 1.9" high at 200 and 3" low at 298yds.
Sounds pretty much like what you just reported give or take a couple tenths of an inch which is about as good as it gets.

Well iam back from the range and had the same
results,i belive Don and Hot core is right
give or take a little on my shooting.
Thanks reloaderlen

AAAAARRRRRGGGGGGGGGGHHHHHHHH!!!!!!!!!!!!

Dan

Dan, I heard you. Or did you really post? As my daughter says, "some days we are all invisible".

Thanks, Larry. One vote of confidence is better than none!

Dan

green 788, make that two if it helps any, lol.

Hey larrys, Dan who???

Thanks Chic...

I guess Hot Core disagrees with me again...

He's still my buddy, though...

Dan Newberry
green 788