In my quest for a scope with either a German #1 or #4 reticle I keep coming across great deals on scopes that have rails attached. Is there an adapter or any way to mount them on a Redfield style base? Are they strictly for claw mounts? Can the rail be removed from the scope easily?

The rail can be removed with a jeweler's saw, a coping saw with metal-cutting blades, or a Dremel tool (if you're adept with it).

George

Look at the German EAW & ERA mounts. Both make lots of pivot mounts for scopes with rails.
The pivot system is similar to the redfield dovetail but far superior.

I don't know of any attachment for Redfield mounts and rail scopes can be tricky to set up without deep pockets.

Several of the old scopes I've bought have claw mounts already on the rails, probably because they take some getting off. You can use these again but they're rarely in the right place for bolt actions and usually need to be smoked and stoned to fit, and the base needs to be soldered on the rifle in just the right place - tres expensive!

I had to use an impact driver to undo the cross bolts in the old claws, after which I just drove them off with a mallet.

I'd bought various Euro mounts on ebay, incl some female rail clamps that the seller said would work with Optilock bases. Then I noticed that some Blaser clamps (cost me about $80) had base holes about the same size in the same place, so I ordered Optilock bases for my long Sako action ($120 posted).

Most clamps have cross bolts to go through holes you drill in the rail but these Blaser ones just had screws to clamp them tighter. Even though they had saw cuts to stretch and then clamp, I had to heat them until any bare bits turned blue before they opened up enough to get them on the rail. I think now that almost all brands must need that treatment and would not be surprised if Continental gunsmiths have gadgets to help keep them open long enough.

Luckily, it lined up well laterally and I only needed to shim under the front base to get the elevation.

Recknagel have a huge online catalogue with lots of choices but the bits might cost $400-plus and a 'smith could charge even more to mount them.