Ok so I searched and found conflicting information on this topic, so I figured that I would post and ask. I am sorry if this question has been raised before, but it is something that I really need to know. Please dont chastise me with “use the search button noob” as I have, but I am checking just to be sure as I need to zero today and dont want to use bad information. Thank you for your understanding and help with this matter.
I have a 14.7" barrel with pinned A2 FH, and my optic is a Trijicon ACOG TA33R8 3X30 (red cevron). I will be using M193 ammo to zero, but due to my current and temporary location restrictions, I can only fire indoors at 25 yards (NOT METERS). I WILL reconfirm at 100 and 200 yards when time permits, but for now i need something relatively close. What is my aiming point with the reticle on the ACOG to have a good approximate zero and so that my BDC is still relatively close?
From what I have understood, 25 yards equates to approximately 375 meters, so I should aim with the target just above the 400 meter line in my optic, right? And that should mean that my 100 yard zero with the tip of the chevron and 200 yard zero with the crotch of the chevron will be close as well? Additionally, how much of a difference in POI will there be when switching to M855?
Thanks guys, Semper Fi.
It should be around the 300m aiming point.
I think you should zero it with M855.
However, you seem right about the rest of your information, but I skipped a little when I realized you wanted to zero with M193.
You’ll have to adjust your zero anyway, as it’s damn near impossible to get a good zero for an ACOG at 25 yards, you need 25 meters, then reconfirm zero at the desired range.
Better to be off on the zero distance by 6’ and using M193 than to not have it even remotely close when it might actually be needed in the interim between running out for M855 and finding 25 meters.
Worst case scenario with the ball and distance change is an elevation tweak will be needed.
Worst case scenario with a completely un~zero’d rifle is dying.
For what it’s worth 25 and 300 match almost perfectly on my Elcan Specter DR’s 4X power BDC reticule when shooting PMC 55grain 223 from a 16" rifle.
In your case I would zero using the 300 BDC line at 25 and be OK with it until you can confirm outside.
This is exactly how I feel, thank you.
So what would be the closer aiming point on my optic, 300M or 375M? Any consensus?
Yeah, I’d use the 300 line and you should be zero’d pretty good for 300 and in (torso accurate), sketchy out past that…but when you get a chance to shoot longer you’ll also be able to fine tune the zero.
I zero’d my TA31 at 25m (on the 300 mark) and was very surprised how close I was at 100m using the chevron tip, just a minor adjustment.
So what would be the closer aiming point on my optic, 300M or 375M? Any consensus?
300…it should be a lot closer than the 400 line…and erring on the side of a flatter trajectory (preferable IMO).
Just regurgitating what others are saying on other threads, but I think that everyone needs to zero at the actual distance of their “zero.” 50 yd is not 200 yds. 25 yds is not 300yds. For a rough zero though, I would say that make sure your groups are about 2" low at 25 yds. That usually gives you a decent 100 yd zero. It probably won’t be on at 100 yards but at least it’ll get you into the ballpark. As soon as you can, of course go zero at the actual further distance. Hope this helps.
It has been a few years for me, but I remember reading all about this in the directions that come with the sight. Now granted the info Im going on is for the TAO1NSN but the way I remember it is you zero at 25 meters with the tip of the Chevron and then when you can re confirm at 100 meters.
I have used this same procudure on 4 or 5 diffrent models of the sight so I would say it works. Your not going to see much of a diffrence in bullet drop out to 300 yards between the two rounds.
Best of luck
Jon
At 25 yards, you can either use the tip of the chevron and zero so that POA is 1.75" higher than POI, or use the tip of the stadia (300m mark) and zero so that POA is about 1/2" above POI. If you are using a good zeroing target with 1/2" divisions, this should be easily accomplished and will put you about as close as you will get using a 25 yard zero.
Perfect! I will do this tomorrow afternoon! Thank you kind sir!