Re: bolt lift kit for my Savage ?
I used to have a 700VS that had been worked over for NRA XTC matches, later an old 40X that had similar treatment. Flicking the bolt back and forth was butter smooth and very, very fast. Never quite lifted the bolt with my thumb, but I could rotate my hand back and flip the bolt open and then back forward using my index finger. One or two of my Savage rifles are almost that smooth... but in general I don't think the cam angles are ever going to allow it to be *that* smooth. On the flip side... I had a custom actioned rifle that would just plain lock up when I'd try to flick the bolt forward like that unless I had my thumb on the tail of the bolt - *any* other way and it locked up like I hit a wall. I tried a friend's action of the same make recently - same thing...
The general idea with the bolt lift reducers is that rather than the inner sleeve riding on against the BAS, you install a small disc that has a ball bearing epoxied in place so that only the very tip of that ball makes contact with the BAS. Being as the contact area is much smaller, and the bearing is hard and smooth, the lift should (in theory) be much less. This all makes more sense if you disassemble the back end of the bolt.
Sharp Shooter Supply (Fred Moreo) makes one that is essentially a .38 Special case cut off short, using the bottom of the case to locate it inside the sleeve, and the rim as the 'lip'. Epoxy a ball bearing in the primer pocket and shorten the sleeve approx. 1/10" (about what the rim thickness is, or else your bolt lift will be *harder* as you are compressing the main spring further). Stockade Gun Stocks (Kevin Rayhill) makes a machined part that does the same thing, just a little less DIY looking, for a few $.
I've had both... and honestly I'm not that sold on them. The dang ball bearing/ BB keeps coming loose. The most bolt lift reduction I've gotten was from shortening the sleeve and then forgetting to put the damn lift reducer back in
In theory the main spring may not hit as hard (not compressed as much), but I never noticed the difference.
On the guns I've had that were super slick, Rem or Savage... I think the 'secret' is they all had a *lot* of rounds thru 'em to smooth things out.