What is the M4 rearsight with the "drum" with different apertures on it?

[greg11]

I've seen them before on Sigs and M4's, I don't know the name of it, so I can't google for an image...

 

[hbean]

diopter sight is what you are looking for.

 

[na1lb0hm]

diopter sight is what you are looking for.

yup.

not to hijack, but do the people that have rifles with them prefer them over the standard ar flip up sights?

 

[browningautorifle]

I think it would be personal. I used them on HKs and I'm cool towards them. I would rather use the type of aperature the ARs have now. Or a minor optic.

 

[F22_RaptoR]

I'm a connoisseur of Diopters you could say

The HK416 is what most people have pilfered them from, Centurion Arms makes an Ar15 height 416 style diopter sight.

They are pretty pricey though, which is why you don't see them more often.

 

[Pooker]

Stickman's Guide to Assorted Rear BUIS.

 

[mufasa]

Those pictures are interesting. I purchased what I thought were (and are marked as) Centurion diopters but there are numerous differences. No numbers, flat head screws, and no "cut out" portion for the 100m/CQB range. I wonder if I've purchased air soft or an older model...hmmm.

 

[TheWharGoul]

These guys?