MRO Dot Size and Parallax?

[kerplode]

I was attempting to zero an MRO on my 11.5" SBR yesterday evening and I noticed something unexpected. As far as I know, the MRO specs a 2MOA dot. At 100 yards, however, it was covering nearly all of the center black bull on a B8 target. This is like 4+ MOA. It was dusk and I had the sight set on '2'. It was barely visible above ambient light level, so it wasn't blooming like it would be on a higher setting.

What gives? Am I misunderstanding how these dots are spec'd? I thought the spec measure was subtension (basically dot diameter = 2MOA) Is that not the case? Do I somehow have a 4MOA MRO despite the specs on the box?

I was also having much more trouble zeroing it than I have usually experienced with Aimpoints. I confirmed zero on the irons at 50yds, then set the dot on top of the front post. I moved the target to 100yds and my first pair was 1" low. Cool, right...2 clicks up and GTG. Well, I put on the two clicks (wow...close together and very quiet!) and fired another pair and they landed several inches high and left. WTF. Another pair went similarly askew in a different direction. Further adjustments just had me chasing it around.

I'm not that great of a shot, but I did my best smooth trigger pull and had the dot centered on the bull as the rounds broke. Maybe I wasn't as careful with cheek weld and centering the dot in the tube as I could have been between pairs. All the shots landed inside the dot, but I guess I expected better precision. Ammo was the IMI mk262 clone, which has been decent in my other rifles, although not sub-moa.

Could be the ammo, but does the MRO have exceptionally bad parallax when compared to a T1?

It got dark before I could screw with it much more so I'll have to try again next time I have a few free hours. Maybe I'll have better results, or just get the rounds landing as close to under the center of the dot as I can and call it good.

[GH41]

I was attempting to zero an MRO on my 11.5" SBR yesterday evening and I noticed something unexpected. As far as I know, the MRO specs a 2MOA dot. At 100 yards, however, it was covering nearly all of the center black bull on a B8 target. This is like 4+ MOA. It was dusk and I had the sight set on '2'. It was barely visible above ambient light level, so it wasn't blooming like it would be on a higher setting.

What gives? Am I misunderstanding how these dots are spec'd? I thought the spec measure was subtension (basically dot diameter = 2MOA) Is that not the case? Do I somehow have a 4MOA MRO despite the specs on the box?

I was also having much more trouble zeroing it than I have usually experienced with Aimpoints. I confirmed zero on the irons at 50yds, then set the dot on top of the front post. I moved the target to 100yds and my first pair was 1" low. Cool, right...2 clicks up and GTG. Well, I put on the two clicks (wow...close together and very quiet!) and fired another pair and they landed several inches high and left. WTF. Another pair went similarly askew in a different direction. Further adjustments just had me chasing it around.

I'm not that great of a shot, but I did my best smooth trigger pull and had the dot centered on the bull as the rounds broke. Maybe I wasn't as careful with cheek weld and centering the dot in the tube as I could have been between pairs. All the shots landed inside the dot, but I guess I expected better precision. Ammo was the IMI mk262 clone, which has been decent in my other rifles, although not sub-moa.

Could be the ammo, but does the MRO have exceptionally bad parallax when compared to a T1?

It got dark before I could screw with it much more so I'll have to try again next time I have a few free hours. Maybe I'll have better results, or just get the rounds landing as close to under the center of the dot as I can and call it good.

Let's say you can hold 2 MOA and the rifle/ammo will shoot 2 MOA. IMO a 4 MOA 100 yard group from an improvised rest using a RDS is more than acceptable. What you need to do is shoot a 5-10 round group and adjust the scope to the center of the group. You are chasing your tail shooting 1 shot and adjusting. Dot size.. I don't think Trijicon ever put a 4 MOA dot in the MRO. I adjust my dot sights to float the target on top of the dot.

[mebiuspower]

Yeah, even if your rifle is 4 MOA capable which it would be with ball ammo it's still a headshot @ 100 yards. It's a wild goose chase on a combat rifle.

[grizzlyblake]

But yeah the MRO is horrible compared to pretty much anything in regards to parallax.

[chef8489]

But yeah the MRO is horrible compared to pretty much anything in regards to parallax.

It is only around the outer edges that it really has a problem with parallax. If you have a proper shooting position on the stock and behind the glass it is not an issue just like a lpvo. If the aimpoint had a larger lense then it would be an issue as well.

[grizzlyblake]

Yeah that wasn't my experience at all. At 25yds very slight changes in cheek weld meant inches difference in POI.

[Sainte]

I just put a green one on my SBR yesterday replacing a Vortex sparc2. I mounted it on a qd AMD in the event it fogs up coming out of the AC car into high humidity.

[rt7]

I purchased a MRO in green and returned it. The dot was not crisp at all. Went back to an Eotech.

[Sainte]

I purchased a MRO in green and returned it. The dot was not crisp at all. Went back to an Eotech.

I don’t Have a single rds that is crisp but, it is due to an astigmatism so I deal with it as best I can.

[rt7]

I don’t Have a single rds that is crisp but, it is due to an astigmatism so I deal with it as best I can.

I have the same problem but I had read the Green Dot worked better for those of us with astigmatism, it wasn't the case for me. The Aimpoint pro had the clearest of all single dots for me.