red dot sight base

[270man]

I have just purchased a Burris FastFire compact red dot sight for my S&W Model 686 revovler. The sight looks like it might be what I've been looking for but I need to find a different base.

I currently have a Weaver-style base that works great for a scope or larger red dot sight, but is way to big for the Burris FastFire. This base has two slots for base cross bolts and the FastFire only uses one of the slots. The forward slot puts the sight too far forward and the rear slot puts the sight over the hammer.

The FastFire user manual recommends a "picatinny" rail. Anyone know of a picatinny rail (or other base) that is small, more compact and will put the FastFire sight just forward of the revolver hammer?

Thanks for any help you can supply,

270man