Re: Zero range for a 338?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: mstennes</div><div class="ubbcode-body">I just picked up a TRG 42 in 338, running a US Optics SN3 5.5x25, my first sight in is at 200 yards, but now I'm wondering if I should zero it 100 or further out than that? This is my first 338 so im in a uncharted area for me. Thoughts? Thanks!</div></div>
Zero it for the shortest range you will either need a point blank zero or a precision zero.
Meaning if you are shooting comps where you need to have a 100 yard zero then zero it at 100. If your comps typically don't go below 300, then 300 it is. With the knowledge of where the 'hold-unders' are. I personally shoot @ 100 and 200 using hold-unders no matter what. It's the same as zeroing @100 you're just using marks above the crosshair instead of the crosshair.
This kind of goes along the line of using a 'point blank' zero out to 300 yds/m.
As noted the 'point-blank' zero is so that no matter what range you shoot within the 'point-blank' range you will hit the kill zone. For instance, if you have a 10" kill zone then the bullet will never rise or fall outside that kill zone if you hold the crosshairs dead center on it. This is pretty much the philosophy of the M16/AR-15 battle zero. Point and shoot. Depending on what bullets you use and how fast you push them, your .338 can have a very long point blank range. If you go big bullets and push them moderately, you may have the same point blank range as a .308. Just over 300 yds/m. But, you'll benefit from the long range trajectory.
FWIW, the 100 yd. zero is base for which a lot of teaching comes from. It's perfectly acceptable to use that and move up (and down) as you range out farther (and back). A quick dial of your scope all the way down and you know you're back at 100 and can go up from there quickly. It's pretty much a set standard by which you can always find your elevation quickly and then dial back up to where you need to be, quickly. Having a longer zero is the same principle, but all the numbers change. Either way, it's based on you KNOWING your ballistics.
I can't say when exactly it got standardized like that but one standard for as many precision shooters in the Armed forces who apply precision shooting isn't a bad thing. Carlos Hathcock had his men zeroed at 700. After he left, his successor had them at 500. He returned them to 700 when he resumed control of the sniper platoon. Army snipers typically zeroed @ 300 during the Viet Nam war.
When I was in, <span style="text-decoration: line-through">we</span> our guys used the Art II scopes on an M21, which were designed to zero @ 200. Being as they were only 2" high @ 100 it didn't make a lot of difference. Not to mention they pretty much had a MAXIMIM effective range of 800m. Anything past that and you could pick for 20 shots and not hit anything that you would hit with a more accurate rifle.
The point is, when the Army finally put a sniper school together, based on the Marine Corps curriculum, someone decided everyone should shoot the same. A wise idea, IMO. You personally, or your unit, can vary as needed, as long as you know the ballistics.
Your rifle, has a much better accuracy factor than those M21's did by a long ways. Same with the M24's and M40's of today shooting 7.62 Match. For personal shooting I see no need to limit the zero to 100 yds. Unless of course you see a need for it.