Full Length AR Rail Options for Clip Ons?

[tekmann2377]

Background - interested in doing some shooting with NV/thermal clipons with my AR's. This is for both a large frame and small frame AR.

What are the current best options for a unified full length rail system for an AR that has a full length upper rail already? PRI offers a one-piece rail which goes from the upper all the way out on the handguard with adequate room for a clip-on, but it seems to only be compatible with the PRI tube handguards.

In terms of the current rail system, it is a Midwest Industries Gen 2 SS rail, which is certainly a decent rail system but is only friction fit to the barrel nut by a clamp mechanism.

The other option is a monolithic upper with a full length rail. I do have an LMT small frame upper as well. However it doesn't shoot as well and is rather overgassed in comparison to the upper in question I would like to use for this. To be utilized for this I would end up putzing with the gas system and redoing load development.

 

[NCgreentick]

I don't think many would be concerned with that since you are not bridging the two unless you are using a prism.

 

[Dogtown]

Yeah, don't worry about that.

I run clip-ons on an LMT MLR and an Aero build without any issues. Obviously the monolithic rail is nice, but it's not a requirement. If you're worried about that particular handguard, then the PRI rail may be a good option - it would raise both the optic and clip-on, if that's something you don't mind.

 

[tekmann2377]

Roger that. To avoid slipping of the rail in the barrel nut I am planning to use some Loctite bedding compound on the interface.

I will do some testing regarding zero shift between the rail types (regular AR rail and the monolithic LMT upper) and will report back if there is anything interesting.

The PRI rails are decent but would require changing the barrel nut. They aren't light or low profile either.

The clip-ons in question are an Eotech ClipIR and a PVS-30. In theory both of these should be collimated so hopefully there aren't any issues with either rail type

 

[rlsmith1]

I've run my PVS30 on a 15" KMR with no issues thus far

 

[jet_lagged]

Midwest Industries rail with some green, gap filling Loctite works just fine for small and large frame AR's and a PVS-30.