Radiused Picatinny Rail for Smooth Free Float Tube?

[Double Naught Spy]

I need to add an accessory rail to an AR15 that has a smooth-sided free float tube. From what I have seen, most picatinny rails have flat bottoms and this will not be ideal to mount on a curved surface. So, I would like to find a rail that is radiused on the bottom so as to help it sit more flush against the free float tube.

Does anyone know who makes such rails?

I realize that the best route would be to buy a new free float tube that already has rails, but compared to what I paid for the upper originally, spending that much money on the upper isn't reasonable. I would rather not spend $150-300 on a whole new tube if I can simply buy a couple rails and tap the smooth-sided free float tube myself.

The closest I have seen is actually a short rail for a Mossberg shotgun receiver top, and I might to that route, but would like other options.

 

[ceyko]

Did you ever find a solution to your problem? I'm basically in the same boat and am about to buy a whole new tube.

I know, I'm bringing an old thread up but it is appropriate as opposed to posting new. My apologies if this is a huge no-no here.

 

[rbernie]

YHM and JP make rail sections that bolt to their respective tubes. The back radius of their rails is obviously established to fit their own tubes, but it may be that your tube is of identical diameter.

Measure your tube diameter and then call YHM.

 

[Double Naught Spy]

No, I had not found a solution, but will check rbernie's suggestions.


Thank you, sir!