36yd zero?!?
- Thread starter JPitts0117
- Start date
Ryan St.Jean
Regular Member
For rifles, typically BDC scopes, which are based on a 100 meter zero getting it on paper closer definitely makes sense. However I would submit that isn’t using whatever arbitrary range as a zero. You are using that 25, 29, 36, 50 meter zero to get on paper for the 100 meter zero. For that using whatever range is closest in the ballistic arc to 100 meters makes sense but it’s still a 100 meter zero.
USMC 36/300 yard zero predates the ACOG by many, many years.
Here is some info (Lt Col Blish) https://robarguns.com/blog/2013/11/24/battle-sight-zero-bzo-who-has-it-right/
Here is some info (Lt Col Blish) https://robarguns.com/blog/2013/11/24/battle-sight-zero-bzo-who-has-it-right/
You absolutely must verify the BDC at the annotated ranges. Even when using an ACOG with the exact barrel length and ammunition specifications it is calibrated for, we found significant deviations once we actually pushed back and attempted to verify. This is the case with every BDC reticle I've ever used and why I shy away from them currently.
OK-5-0
Member
When I began caring a rifle as a profession, I remember zeroing at 25 yards with irons and 36 yards for our Eotechs. I can not remember if I got any other answer than “that’s what the Troopers do” as a reason for those distances. My how times have changed. Much more different nowadays.
Yondering
Regular Member
No, not really; none of those closer ranges coincide to a 100 meter/yard zero. For most military rifles and the 5.56 cartridge, a 100 meter zero only meets the POA at one point - 100 meters. It's the closer or farther zeros that cross twice.
When a 36 yard zero is discussed, that is definitely not for just getting on paper to confirm a 100 yard zero. A 36 yard zero generally coincides to a 300 yard zero, and those who use it keep it that way.
ArmedNovelist
Amateur
Thank you for that additional information!
Sunshine_Shooter
Established
I hadn't considered that max point blank range would change with the target. Just when I think I know what I'm talking about, I go and learn something that I feel like I should have known a long time ago.
And thanks for the kind words about my writing.
That's a fine article, and Freddie Blish is a good dude. However, much of the info in that article applies not only to iron sights, but some particular iron sights.
If you're zeroing an RDS, scope, or simple BUIS, you'll have to dig deeper into the ballistics and have some idea of how you plan to use your rifle. Ideally, you'd have some room to work with and play around with different zeros and holdovers. Steel targets are super useful for this.
If your optic has some sort of BDC, I'd strongly recommend zeroing it per the manufacturer's instructions and working with it to see just how close it is to reality with your barrel/ammo combo.
Just kinda went through this last weekend at a training course. We started off getting chrono numbers for our preferred ammo, then plugged that into Strelok and seeing what zero range we liked with our reticles. For me, with a 12.5" BCM, Steiner P4xi, shooting 75gr Gold Dot, I found that a 100 yd zero gave me the best combo of hash marks. 100/219/308/397/486 and was able to use this setup to get easy first round hits on mini-IPSC steel at 200, 300, 400, and 485. Zero range, IMO, needs to be a decision made based on use, environment, ammo, optics, and skill level combined with a lot of testing at real distance. Not what the latest HSLD Instagram warrior is doing.
ccw1911
Newbie
I see way too often people zeroing their AR at 25 or whatever the yardage of the day happens to be on the internet that week and then never going any further. Get out and shoot your rifle at all the distances you can access, learn where YOUR rifle shoots, this not only confirms your zero but also trains you as to what your rifle will do and what you can do. Not just shooting a 5 round group, shoot several and teach yourself where your rifle shoots and what sight pictures look like at those different distances, do it enough you don't have to think about it at least for the most likely engagement distances for your environment. There is just no substitute for time behind the gun.
Fatboy
Established
The best piece of advice I was ever taught when it comes to zeroing was very simple. Figure out the max distance you will engage a target under the conditions you will use your rifle. Then zero at that distance. After that, learn your mechanical offset for up close and your hold offs at every other distance you shoot.
In my case, I "grew" up with the 25/300 zero in the Army and came to realize the bullet was all over the place at different ranges. Then we figured out the average engagement distance in Iraq was 200 or less, so we switched to that. Now that I'm a cop, I use a 100 zero because that is the furthest I can articulate having to shoot at someone in my area, and there is no hold off to do it.
In essence, you have to figure out your use, then zero to make the most of that distance.
In my case, I "grew" up with the 25/300 zero in the Army and came to realize the bullet was all over the place at different ranges. Then we figured out the average engagement distance in Iraq was 200 or less, so we switched to that. Now that I'm a cop, I use a 100 zero because that is the furthest I can articulate having to shoot at someone in my area, and there is no hold off to do it.
In essence, you have to figure out your use, then zero to make the most of that distance.
JPitts0117
Regular Member
I looked at the target on his website. Target states for 5.56 55gr Fuji, no mention of particular barrel length... in case anyone was wondering
JPitts0117
Regular Member
Fmj not Fuji.... stupid autocorrect