Just put a new scope on my grandpa's m77. I used steel rings from ruger. Machine work leaves a little to be desired but they torqued down to 65 inch pounds without issue. Being that they are steel, im optimistic they will hold up well. I was informed by someone more in the know than me that the ruger branded rings are the rings to go with on the m77
Yes, the machining can be rough on the Ruger rings. But if they are lapped, they can provide a perfect, precise cylindrical fit. Before I got a lapping kit, I made some severe marks on scopes from Ruger rings. After lapping, I've found they leave no marks at all. This was all done torquing the rings to 15-17 in-lbs. I now use one of those aluminum bar sets with a ring that slides back and forth to confirm perfect alignment.
With a set of the Leupold Ruger rings, I was able to get perfect alignment and mounted a scope for a while. But upon changing to another scope, the rings had left strong marks on the scope. The Leupold rings had little grooves inside that concentrated the stress where they contacted the scope (the grooves were still there because I didn't have to lap too much in that case). I don't know if this has any internal effect, but the external effect is unpleasant and I threw the rings in the garbage.
I also didn't like how the Leupold Ruger rings connect to the receiver. With the set I had, the base screws were slotted and small compared to the base screws on Ruger OEM rings. To put them on at the recommended torque value (I forget the number), I felt nervous that the screwdriver might slip out. Maybe that's my own skill issue but I have steady hands and good grip strength. When I took the rings off, I ended up partially stripping one of the base screws. I see that resulting from an inadequate combination of screw size and metal strength for the recommended torque. With the Ruger ring base screws, I never had a problem with putting them on and off. The Ruger base screws are also slotted, but pretty big and with a gunsmithing screwdriver head that fits properly, they are easy to work with. I only used the Leupold Ruger rings at the time because I couldn't find Ruger rings for 30 mm.
The Alaska Arms QD rings are very good quality. I had some for a while with a rifle I ended up selling. It was a Ruger Guide in .375 Ruger, and I was experimenting with the idea of having a 3-9x40 and a 1-4x20, to be able to switch back and forth for different purposes. This was before I got into lapping, but the AA rings came with friction paper and recommended using it. There was enough natural alignment in the receiver cuts on that rifle that the AA rings were aligned well enough, so there was no surface damage to the scopes if I recall correctly. Like most manufacturers, AA advises against lapping, but I could picture how in some M77s the receiver cuts might be a bit off and lapping may be required if you want perfect alignment.
I tried the Warne Ruger rings as well. As with all vertical split rings, they work by bending around the scope and it's generally impractical to lap them because you can't lap at the "final" torque where they clamp around a scope. The pair I tried were pretty well aligned on the rifle, but they leave a mark because of the stress involved in bending the ring to fit around the scope. (Whether that affects scope function has been discussed by others on this FORMum and I have nothing to add.)
So, if you want QD, I would recommend the AA rings. If you want fixed rings, I don't think you can do better than Ruger OEM rings, provided you lap the ever living snot out of them to remove machine and/or rough surfaces from the factory mold. Or mount a rail like others have suggested. I've never tried one of those but many people like them.
