Rookie deciding on 1/3 co witness or absolute. Help

[Offensive]

Have an 10.5” pistol build. Flip up back ups, trying to determine best set up between a 1/3 Co witness or Absolute. Opinions needed please and reasons for them.

[sbrown3]

Keep front sight up, rear sight down, use lower 1/3

[Clint]

Sight height is mostly about head position.

For standing/walking a higher center line is better.

For prone/bench, a lower center generally works best.

For the use case of a red dot, the 1/3 or a little higher is generally good.

[titsonritz]

Check out this thread if you already have not...
https://www.m4carbine.net/showthread.php?17049-Explanation-of-Co-Witness

All my RDS sit on 1/3 co-witness mounts. I have them with no BUIS sights, fixed FSB with folded rear and with both front and rear fixed sight. I'll probably get 1.93" mount one of these days to check out too. As Clint mentions above, unless you primarily shoot prone/bench, higher is better.

[Offensive]

I had not read that. Very interesting read. Thanks for the point in that direction

[chef8489]

If I have a fsb I do a lower 1/3. If I have flip sights I use absolute.

[ggammell]

Keep front sight up, rear sight down, use lower 1/3

Why??

[rockapede]

I can barely stand to shoot an absolute mount anymore; I feel very cramped in any position but prone. Heck, most of my mounts aren't even lower third anymore (only have one of those left); they're all 1.93" or 2.26" now. Going forward (FOR ME and my facial geometry/body type), RDS will go in nothing lower than Unity Fast mounts and LPVOs will go in nothing lower than 1.93". Precision guns still get 1.5" mounts but they're shot prone much more; even then, reports of tall mounts being totally unworkable prone are highly exaggerated, IMO.

I don't care about irons anymore unless policy requires me to.

[Devildawg2531]

I have an FSB and back up iron sights. I use an absolute co-witness with my AimPoint T1 and love it. The FSB doesn't obscure the dot and I can flip up the BUIS and use very easily with no adjustments. Absolute co-witness just seems natural to me compared to lower 1/3.

[markm]

Why??

For me, the RDS acts as a ghost ring should it be dead or off in an emergency.

[ggammell]

Ok. That’s like third order effects.

RDS goes down, flip up both sights. Rear sight goes down, shoot through the tube. Got it.

If one part of the BUIS goes down, after the RDS goes down, What are the chances that gun is still serviceable to begin with?

[JediGuy]

Ok. That’s like third order effects.


I’m not sure, but I think that the ghost ring idea would be in lieu of either a) not having a buis or b) not taking/having time to flip up the buis.

To the original OP, the Lower 1/3 is more natural placement for me. However, there is nothing at all wrong with Absolute. I don’t shoot prone ever right now, so I can’t compare that.

[Pappabear]

I like the 1/3 for my needs and wants. YMMV

PB

[boomer223]

Absolute Co-witness

- Smaller difference between point of aim / point of impact (hold-over) and subsequent math to compute, especially when shooting from canted positions.

- Allows quick confirmation of RDS zero, by flipping up BUIS and checking alignment.

- Same stock/ cheek-weld muscle memory.

[1168]

Ok. That’s like third order effects.

RDS goes down, flip up both sights. Rear sight goes down, shoot through the tube. Got it.

If one part of the BUIS goes down, after the RDS goes down, What are the chances that gun is still serviceable to begin with?
No, you use the front post through the dot as immediate action if you attempt to engage a target and find no dot. Flipping up the rear, and/or tossing the RDS, is remedial action.

[Five_Point_Five_Six]

No, you use the front post through the dot as immediate action if you attempt to engage a target and find no dot. Flipping up the rear, and/or tossing the RDS, is remedial action.

Agreed. It's quite effective as well, and can be used a lot further than some might imagine.