awkward/obscure scope mounting

[subsonic]

I have a Ruger 77/44magnum ss with a integral suppressor which is a 1 3/4" alloy concentric tube thats runs back to within 3/4" of the action. I want to fit a IOR 2.5-10x42 to it but I really need a sloped mount as a subsonic 300gn cast bullet has a pretty round trajectory.
Has anyone got any suggestions such as:
Drill and tap the action (or is it too hard to drill and tap?) and fit a sloped mil std 1913 base.
Fit some giant Burris signature rings and install the eccentric inserts? I don't think they will be anywhere high enough though.
Fit burris weaver base adapters and then use some sort of weaver base ring (but this way I don't get a sloped base effect).

Any other suggestions options welcomed.

Cheers.

[subsonic]

Hey Guys. Someone must have some bright ideas.

[Pete Lincoln]

I've seen a picatinny rail some where that clamps onto the rugers integral bases, whats the max range you'll use the rifle at? maybe 100m to 150m, you should be able to fix something up to get you that adjustment from the scope easy enough.
Pete

[subsonic]

I had a 6.5-20x40 leupold on it just for group shooting and it ran out of elevation before 100m with subsonic 300gn ammo.

[Brien]

you might try a gunsmithing blank if you have a smith close by .. one might be able to get you a 15 or 20 moa sloped base fitted to your receiver..???
good luck..
Brien