Height over bore for Sig Romeo5 Tread on standard flattop AR?

[BTLowry]

Stumbled onto a method used by Frank Proctor to 50/200 zero a 556 AR with 2.8" height over bore

I have searched the www and cannot find the answer for my combination

If I end up measuring it, what is the best method?
No way to just hold a measuring device center of red dot to center bore

Printable targets are optimized for 2.8" red dot height over bore

Figured there was either someone who knew or someone knew an easy method that I have not thought of

[MadHatter]

Put the gun in a vise, chamber a laser boresite rounde, put a white piece of paper 1" in front of the muzzel, use a level to run a strait line, tape a ruler to the paper against the line you just made, adjust red dot to 2.8" on the ruler....?

[SmTx]

Sounds like it's just a bore sighting process?

[PVDT]

I’m assuming that your concern to be exactly 2.8 over the center line of the bore is for ballistic calculations. If so, I wouldn’t worry too much about it. The “usual” one piece mount for a regular scope puts the center line of the scope at or about 2.6” over the center line of the bore. The difference for 2.8” and 2.6” at 1k yards is less than .25 MOA. That’s less than 3 inches. But for general calculations, the centerline of the bore to the top of the rail on a mil-spec AR is 1.211 inches.

[BTLowry]

This link explains it and you can download targets for free.

https://www.frankproctorshooting.com/frank-proctor-shooting-10-yard-carbine-zero-target/?utm_source=Klaviyo&utm_medium=campaign&_kx=OvdsCaTf6pZeXmoGyfDjGNq9geMx31Kn--YK7iRV16U%3D.USvzjg

My understanding is you get gun hitting where it should on this specific target and your 50 and 200 yd should be dead on

I just don't know if the height over bore being off (say .25) has much if any affect on where it hits at 50 or 200

Not trying to shoot the wings off a gnat at 100yds but don't want to be wasting lead shooting at coyotes, pigs and the like

[BTLowry]

I’m assuming that your concern to be exactly 2.8 over the center line of the bore is for ballistic calculations. If so, I wouldn’t worry too much about it. The “usual” one piece mount for a regular scope puts the center line of the scope at or about 2.6” over the center line of the bore. The difference for 2.8” and 2.6” at 1k yards is less than .25 MOA. That’s less than 3 inches. But for general calculations, the centerline of the bore to the top of the rail on a mil-spec AR is 1.211 inches.

This is what I needed to know

Posted at the same time, thanks

[andre3k]

I keep a dope chart on my ar stock to remind me what my hold offs are. I use a 50/200 zero on most of mine and at 10 yards I'm right at 2 inches low.

Sent from my SM-S918U using Tapatalk

[Clay C]

I've found 50/200 to work well with just about any mount height. It's a red dot. Don't over think it. I usually zero at 50 and confirm on steel at 200. If it is way off then adjust.