Advice request-mounting 3x prism scope in front of MBUS = horrible eye relief

[WalterJones]

I'm sure this has to have come up before but I'm just not finding a thread while searching.

I mounted a 3x prism scope on one of my AR's. Problem is, with an MBUS rear sight the eye relief is such that the charging handle is about a quarter inch away ftom my face and the weapon just doesn't feel comfortable.

Threw it on a couple other rifles with different rear sight profiles and had the same result.

The easiest solution would be to remove the rear sight, but I sleep better having a set of sights on a rifle even if they are polymers.

Any suggestions appreciated.

[sbo80]

not many options if you want to stick with your hardware. Offset irons. Different prism. Get a red dot with a flip to the side 3x, so you can mount the mbus under the flip, and just use one or the other. Maybe just get a stock with a different LOP, and a steeper handgrip like a magpul k2. Nose-to-charging handle works for lots of people.

[WalterJones]

Thanks for the tips. My purpose in trying out the prism is that my astigmatism has gotten worse so red dots are becoming a thing of the past for me.

[OpticsPlanet]

Could always move the rear sight in front of the optic as well

-Matt S.

[mshill]

With a prism scope why do you need backups. Since prisms have an etched reticle you don't have to have illumination. Unless the glass breaks there should be no need for backups.

[WalterJones]

With a prism scope why do you need backups. Since prisms have an etched reticle you don't have to have illumination. Unless the glass breaks there should be no need for backups.

Well, because things tend to fail when you need them most.

I ended up cutting the QD mount down a little and shaving a little off of the front facing side of the mbus sight. Was able to move it up two slots in the rail, to a point I feel much more comfortable with. Would prefer one more slot, but I can live with it now.

Removed and put back on several times and its holding its zero well.

[donnrcp]

[k1dude]

If you want a longer eye relief that what's offered by magnified prism scopes, you'll have to move to a LPVO. There's plenty of options in the 1-4, 1-6, 1-8, 1-10, and 2-7 range with eye relief between 4" and 9.5".

It's a better option anyway because you get CQB capability at 1x. The only penalty is a few ounces of extra weight.

[Mr. Meeseeks]

Could always move the rear sight in front of the optic as well

-Matt S.

This, like a Canadian C7A2.