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Please Help with 308 Zero

Trying to figure out my M1A rear sight adjustment for 200 yards using a 50 yard data point.

Firing a 30 cal M1A SOCOM (16"), making just shy of 2400 fps, using 168 gr SMK in front of 42.0 gr of 4064.

At 50 yards, holding 6 o'clock on a 7" ring, I'm getting a consistent group 2.5" below the bottom of the ring, equating to 6" below center on the 7" ring at 50 yards.

Wanting to hold 6 o'clock on a 7" ring at 200 yards, and hit center, what adjustment do I need on my elevation knob?

Note - I'm also posing this question on the CMP site, but wanted to start with you experts.

Thank you!
 
Haven't shot at 200, otherwise wouldn't have asked the question. Shooting an informal CMP match at 200 on Saturday, so hoping to make a rear sight adjustment before then to make sure I'm on paper, will then make tweaks during the sighters to put myself in the center.

Thank you.
 
I put your data into Strelok and this is what I came up with. There is a free version if you want to download it and play with it yourself.

Screenshot_20201203-092611_Strelok Pro.jpg

I am not sure how the rear sight would adjust from here but this will at least give you an idea on the trajectory.
 
Haven't shot at 200, otherwise wouldn't have asked the question. Shooting an informal CMP match at 200 on Saturday, so hoping to make a rear sight adjustment before then to make sure I'm on paper, will then make tweaks during the sighters to put myself in the center.

Thank you.
Using the 168 SMK @ 2400 FPS, you should need around 4 minutes of correction to go from 50 yards, to 200 yards. This will put you in the black as far as elevation goes. So that would be 8 clockwise clicks on the rear sight. Are you using the NM hooded rear sight? If so, this will gain you a half MOA elevation in either direction, depending on which direction the elliptical aperture is rotated when you do obtain your zero.

Enjoy the match.
 
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I was able to free up some time on Friday, and will make a special trip to the range's 200 yard line in an effort to find my zero before Saturday's match. Thank you for all the responses. I'm starting with 8 clicks, and hopefully see a hole on the first shot.

And no, I'm not using the NM hooded rear, just stock peep hole.
 
I was able to free up some time on Friday, and will make a special trip to the range's 200 yard line in an effort to find my zero before Saturday's match. Thank you for all the responses. I'm starting with 8 clicks, and hopefully see a hole on the first shot.

And no, I'm not using the NM hooded rear, just stock peep hole.

Okie doke - one bit of advice: give yourself one extra click when you finally get your correct zero. This will put you slightly high, perhaps in the 10 ring when you begin shooting. Once you're in your initial position, your muscles will begin to stretch out, and your position will drop slightly. The extra click will allow you to 'sag' into the 'X' ring.

Remember, if using a front sight post: 'Lights up, sights up, lights down, sights down' if you're going to use the classic lollipop sight picture. If you use a 'Navy hold' or edge of frame hold, this doesn't apply.
 
Thank you for all the help and tips! Got myself on paper today, but there's a funny (?) side story.

Loaded today and tomorrow's rounds to a CBTO two-thou jump, and was running the testers manually today. When I got home, I decided to pre-load my 2 and 8 magazines for the rapid fire stage. Guess what? The COAL was too long for the mags by about 80 thou. D-oh!

So I re-seat the SMKs just short enough to fit, somewhat invalidating what I did today. Just hoping the change in pressure and velocity won't matter too much during my sighters. Can't imagine it will make a huge difference at just 200 yards.
 
If your six inches low at 50 you’ll need 12 moa to zero at 50 then 4.5 more to get to 200 so that’s 16.5 moa. I’m not sure if the socom has half or full moa clix
 
MSgt. Jim Owens used to publish in his data books, a good general rule of thumb for figuring out come-ups which worked well for the 168 gr. HPBT travelling between 2400-2500 fps: 2-2-3-3-4-4-5-5-6-6.

Thats the number of MOA you would need to hit the black, from 0-1000 yards. I've used it, when learning theoretical zeroes, going from a 200 yard range (which I have) to an 800 yard range(which I don't). It will put you somewhere in the black, and therefore able to adjust to the 'X', in two sighter shots. Try it out, and I think you'll be amazed at how quickly it works.
 

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