My head hurts!

[A. F Medic]

I have a Red Dot on my new to me A1/A2 build. I was going to take the rifle to the range and sight it in at 25 yards with an 1.5 inch rise. This usually puts my deer rifle a little high at 100yards. I still shoot it at 100 yards to verify.

Does that sound alright to the forum? I have looked at many charts and really do not know what to think. I did not know the 55 gr rises so much (trajectory)

Before I shoot, I thought I would throw my question out to how youse guys do it. I am shootng Federal FMJs.

Check this out thanks to the AR15.com...Effects of zeroing distance on trajectory (55FMJ)

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[Stevo]

How is your red dot mounted? If it's on the carry handle you've got a massive amount of sight offset to contend with. If I follow you correctly, you're going to zero it to shoot 1.5" below your aiming point at 25yds? That should be in the ball park for a 50m zero.

My AR's are both zero'd at 50m. That's roughly back on at 200m, so I'm good for shots on IDPA-sized targets out to 300m +.

[A. F Medic]

It is on the carry handle. What do you mean by sight offset?. The up and down? I think I see a problem there on my rifle...

[Roscoe Snyder]

This may be worth getting:
Big Hole Upper Receiver, Assembly (b) | Daniel Defense

[Stevo]

It is on the carry handle. What do you mean by sight offset?. The up and down? I think I see a problem there on my rifle...

By offset I mean the height difference between the bore line and the sight line. It's not a huge issue, you just need to figure out where your rifle shoots at various distances. You may find, for example, that if you zero it at 50 yds that it will shoot higher than you expect it to at 100 yds.

[A. F Medic]

You said it!!! Sighted it in at 25 yards perfectly. No 50 foot back board was up so I went to 100.

Kept lobbing them right over the complete target !! Only knew that as I was tearing up the shale back stop real good

I will have to wait until the 50 ft backing boards are put back to verify bullet placement at that range. Then on to 100 yards.

May have to have bullet impact low at 25 yards and then see it at 50. Thanks111

[Stevo]

If you had your POA and POI the same at 25m with a carry handle optic you'd probably hit zero again at 300m!!!

With your setup I'd zero it to hit about 1 1/2 inches low at 25m. That should be good to get you on the paper at both 50m and 100m without being too high at 100m.

With my ARs and VZs I always zero about an inch low at 25m, get it dialed in, the move to 50m to fine tune the 50m zero. I find I don't have to chase it around as much as just zeroing at 50m.