I have a .308 with 24 inch barrel which is typically loaned to junior shooters who I am mentoring. Shooting 175's with an average of 2650 fps, and using a 1/4 MOA adjustable sight, a good hold can get a bullet right-in there to 297 yards with 18 clicks on the sight from a 100 yard zero. With 19 clicks on the sight a good hold can get a bullet right in there at 315 yards. Now, since in competition a shooter would be shooting at 300 yards, it's apparent this rifle cannot be exactly zeroed for 300 yards with the velocity of 2650 fps. This is not a big deal at 300 yards but not having an average muzzle velocity which will get a trajectory for a pinwheel X at 1000 yards will mean lost points. Thing is, this sort of precision is not likely to be realized by most shooters competing at any but the highest levels of competition. But for those here who are gaming here's a tip.
With whatever load you're shooting at 1000, record all strikes that are called right-in-there for elevation. Thereafter, connect the dots to get what should be a somewhat horizontal line. This line could of course intersect the X and you would obviously want to leave your load alone. But, if your horizontal line appeared above or below the X, a tweak to raise or lower average muzzle velocity could be worth while, since a zero which consistently produces hits across an imaginary horizontal line intersecting the X of the X ring will buy points when wind is not correctly countered. For example, the shooter could catch a scratch 10, which without a definable zero through velocity adjustment would yield a 9.
Now, this tip is not likely to help anyone who cannot hold to produce a horizontal line when connecting the dots, and it will not aid a shooter who has anything other than the lowest ES and SD for their hand-loads using a temperature insensitive powder. Nevertheless, for those who can hold elevation, this is the icing on the cake strategy to better assure a win.
I actually use this technique with my Service Rifle shooting with irons at 1000 yards, since I want all the help I can get from my ammunition to hold a decent elevation, since my eyes are suspect. That's to say, even with a sharp post and a well defined target, I'm not always confident that my perception of a good 6 o'clock hold is a consistent perspective on the matter.
With whatever load you're shooting at 1000, record all strikes that are called right-in-there for elevation. Thereafter, connect the dots to get what should be a somewhat horizontal line. This line could of course intersect the X and you would obviously want to leave your load alone. But, if your horizontal line appeared above or below the X, a tweak to raise or lower average muzzle velocity could be worth while, since a zero which consistently produces hits across an imaginary horizontal line intersecting the X of the X ring will buy points when wind is not correctly countered. For example, the shooter could catch a scratch 10, which without a definable zero through velocity adjustment would yield a 9.
Now, this tip is not likely to help anyone who cannot hold to produce a horizontal line when connecting the dots, and it will not aid a shooter who has anything other than the lowest ES and SD for their hand-loads using a temperature insensitive powder. Nevertheless, for those who can hold elevation, this is the icing on the cake strategy to better assure a win.
I actually use this technique with my Service Rifle shooting with irons at 1000 yards, since I want all the help I can get from my ammunition to hold a decent elevation, since my eyes are suspect. That's to say, even with a sharp post and a well defined target, I'm not always confident that my perception of a good 6 o'clock hold is a consistent perspective on the matter.
