Thoughts on Zero for 10.3" barrel

[rxer311]

I have always been a fan of a 50 yd zero for all my general purpose rifles with 14.5-16" barrels. Because of the velocity difference out of a 10.5" barrel, should I rethink my zero?

In pistol configuration I did zero the rifle at 50 yds but never took it out to 100 yds. Being an SBR now, I really don't forsee any situation that I would be using it past 50 yds as I have other rifles that can do that job more handily. What I noticed is that being zeroed at 50 yards, that POI is about 6-8" lower at a CQB distance of 7.5 yds. Basically if I would aim at the very top of the head of a silhouette target I would get hits center head.

I was thinking that maybe a 25 yd zero may be more beneficial for me with less elevation holdovers between 5-50 yards but still take me out to 100 and beyond if really needed.

Am I overthinking this (I probably am)? But since I changed up my setup from pistol to SBR and just changed up my optic I am going to rezero the rifle on my next range trip. Thought I might get some info on what kind of zero you are using for a setup similar to mine.

[voodoo_man]

Max Point Blank Range Zero

a calc: http://www.shooterscalculator.com/point-blank-range.php

more info: https://www.americanhunter.org/articles/2017/7/17/learn-your-maximum-point-blank-range/

Basically zero the gun to the first POA/POI of your optic vs bullet weight vs barrel and then figure out where it intersects again further out, each combo is different.

The whole point is to not do math and be +2" -2" until your second intersect.

[rxer311]

Thanks! That website was a big help. 29 yd zero looks to be the best for my application. Close enough to 25 yards so I plugged it into the trajectory calculator and I should be within 2.5" out to 250 yards with a 25 yard zero. I believe the 25 yard zero would be the best for me in this application.

[alamo5000]

I recall a thread here somewhere where someone put up data showing data on SBR loads. If I am not mistaken it was Molon who put up the info. He had some very specific ammo recommendations for SBRs that still have good terminal ballistics. Based on his tests I bought a bunch of Hornady 75gr bullets which according to what we all discussed has good terminal ballistics out to about 50 yards out of a 10.5 barrel.

Shooting a target out to 100 yards is not a problem and would still cause major problems for the bad guy. I shoot my 10.5 on the small man shape targets at 100 all the time with a 1x optic.

You came up with what I used. I did a 30 yard zero. Just zero for whatever ammo you are using. I am on my last little batch of .55 grain ammo but after that I will work up a 75grain load and just try to keep from having to fiddle around zeroing all the time.

[Former11B]

I’ve always learned, no matter what optic or rifle I’m using, where the bullet would impact versus where my point of aim is, for some crucial short range situation. You can buy or make targets for that specific purpose

[BoilerUp]

I’ve always learned, no matter what optic or rifle I’m using, where the bullet would impact versus where my point of aim is, for some crucial short range situation. You can buy or make targets for that specific purpose

That's one thing I like about the EOTech reticle. The bottom of the circle works well for close-in ranges

4762

[voodoo_man]

Anything that requires doing math or thinking at close range distances isn't going to work well.

Put the dot on the target squeeze the trigger a few times, the zero should support that.

[BoilerUp]

What I noticed is that being zeroed at 50 yards, that POI is about 6-8" lower at a CQB distance of 7.5 yds.

Something isn't right there. You should be within the 2.6" height over bore between your muzzle and zero range (regardless of 25, 50 or 100 yards zero).