Reloading according to yardage

[ARlife4me]

Try it at 1000, and if the OP was talking about holding over, that's different, and not what seemed to be implied to me.

Gravity and velocity decay are both real and so is trajectory, as well as environmental changes. You either have to increase or decrease MV to retain zero, or adjust or hold over. The further the distance, the more pronounced, and the more the environment changes, the more it'll affect things. You can account for drop (gravity) alone by adjusting MV, but not changes in the environment, and those effects grow exponentially as distance to target increases.

Plus, that's not even factoring in being within an accuracy node by adjusting MV by powder charge to retain zero without ever needing to dial or hold over.

The 100gr does have more velocity to meet the 600 yard impact as the 140 does. At 1k I know it will be a challenge and wouldn't try with either load. Going that distance a different load would be worked up, but for only 1 bullet weight.

Are you trying to say that with either a 100gr or 140 grain bullet, you can hold right on a prairie dog anywhere from 0 to 600 yards, and get hits without doing anything to account for elevation? What's your zero? Is this prairie dog town located on the moon?

Sighted at 250 as it being the little difference in the velocities chosen for the 2 (100 & 140gr). It took some experiments along with Sierra's #5 ballistic info. It worked for me as ymmv. I tried using 85 and 140's, but the weight difference was to great. 110 and 140 was more ideal.

 

[ARlife4me]

Is he shooting with a Tracking Point system? That would do it. 100 to 1000 without adjusting scope or POA. Just hold and pull the trigger until it shoots.

Was that offered in the '80s, because I was using a Leupold 3-12x40(?). No batteries powered scope for me at the time. Not sure of the objective size.

 

[SupressYourself]

The 100gr does have more velocity to meet the 600 yard impact as the 140 does. At 1k I know it will be a challenge and wouldn't try with either load. Going that distance a different load would be worked up, but for only 1 bullet weight.

Sighted at 250 as it being the little difference in the velocities chosen for the 2 (100 & 140gr). It took some experiments along with Sierra's #5 ballistic info. It worked for me as ymmv. I tried using 85 and 140's, but the weight difference was to great. 110 and 140 was more ideal.

Ok, so you're saying that you have a 140gr load, and a 100 grain load, and you tweaked them both to have the same POI at 600 yards. I don't really understand the point of working up loads with that as a goal, but it's possible.

At first it sounded like you were saying you had a load that shot so flat that you could aim right at a prairie dog anywhere from 0 to 600 yards without adjusting for elevation, which is not possible.

 

[Sealesniper]

Very true statement. I bet he has a load that will hit the sun too. First response was the best "Jenous". I wonder how he walks around with his head that far up his own Ars. Your neighbor is not Joe Biden is it? He just stated he has reduced the deficit by more than any other president in history. Raised Joe, not lowered.

 

[Tiny Tim]

While theoretically possible, the arc, mv, and energy at 100 yds would likely reder it practically useless. You would have to account for whatever max ord is at 1k at every range.

 

[Sprocketman]

Using Hodgdon load data for a 6.5CM shooting a Hornady 135gr A-Tip using 38.0gr of H4895 (a full grain over max published load), Quickload is telling me 2888 fps. a 1000 yard zero requires 34.137 MOA of elevation according to JBM ballistics.

Using Hodgdon's guideline of safely reducing max published load (37.0gr in this case) by multiplying by 0.6 gives us 37.0 x .6 = 22.2gr. Quickload shows a muzzle velocity (using 26" barrel length and 2.800" OAL) of 1841fps. Using 1841 fps and correcting for zero distance in JBM, I find a 538 yard zero results in an elevation of 34.124 MOA....or nearly exactly the same as the 34.137 MOA to zero at 1000 yards at 2888 fps.

A muzzle velocity of 718 fps will put you nearly on the bullseye at 100 yards......but not sure what powder you would use for this???

This is all assuming you don't touch the scope after zeroing at 1k....just adjusting your load, and resultant muzzle velocity, so the bullet is centered on the bullseye at a given distance.

Methinks it would be easier to dial the scope for distance....

.

I did the same analysis as choprzrul except I randomly picked a 103 gr 6mm ELD-X at a random muzzle velocity of 3500 fps (high I know). That gives a 100 yrd rise of 20.1" for a 1000 yrd zero (according the Hornady's ballistics calculator). A muzzle velocity of 940 fps will give a 100 yrd drop of 20" for that bullet based on the drop calculator on www.cleverinsite.com. Not sure what that 100 yrd load would be, but it's technically possible.

Maybe the neighbor is just holding on the bull and hitting way high or low depending on his zero and range