Want to KNOW about scope swapping?
ONLY Way To KNOW is to Do It Yourself....
Best tool I ever bought for general gunsmithing work and maintenance was a Bushnell 74-3333 boresighter/collimator. The expanding arbors aren't the greatest design, but the tool works, and the grid (collimator) allows much diagnostic evidence to be gathered for understanding scope and mount system dynamics.
About the best platform for scope swapping is the AR 15/10 flatop receiver. As long as your barrel is mounted on a true basis to receiver shoulder; (barrel shoulder concentricity and precision ground mate surface of barrel extension), you have a reliable index to work from. Basically, the A2 rail is a picatinny pattern of uniform dimension on all flatops, just longer for AR-10s. Using your collimator you can verify that scopes mounted & sighted on first rifle will align on same vertical grid line on 2nd rifle. Might be some issues if you can't remove flashider or brake before doing your testing. Also WILL BE issues should your brake or hider interferw w/bullet exit.
So... Once verify your vertical alignment on both weapons w/same scope and mount, you can test at the range. Ideally, your zeros on each weapon will have very close vertical index, but horizontal will differ due to distance of the zero and Ballistic Coefficient of the bullet and velocity. Another great reason to keep a Log Book... To assure as many variables can be eliminated, use a inch lb torque wrench to torque all scope system fasteners, and the same mount position for each ring or mount set.
Got an integral rail receiver on both bolt rifles you want to swap between? Most won't. Lots more variables to solve for on bolt rifles than the AR system; maybe not "more", but much wider range of accepted tolerances due to receiver size and mount placement variations. Lots will depend on your base system. I have found consistency with Win 70 LA & SA actions when using picatinny rails of identical mfr, and Weaver style mounts. There are also important variations with Express and classic SA receivers (classic compact) which do not have picatinny rails available from any recognized mfr.
With a tool like the Bushnell 74-3333, you have means to isolate problems on a great many elements of your rifle system. Weak link (there's always one) is the expanding spud system. Tasco did make a boresighter with specific bore diameter arbors, but I've never used a Tasco. Redfield might have offered one with bore specific arbors, iirc.
Lots of interesting opportunities for scope-swapping, just need the diagnostic tools to do so and verify repeatability.
Even more interesting is the opportunity, through precision handloading, to taylor the ballistic path of all rifle ctgs you shoot/load for to close ballistic performance. Use bullets with close as possible Ballistic Coefficiency and taylor velocity to same level. Essentially, you'll be shooting the same ballistic curve for all your rifles.
If you don't do your own gunsmithing and handloading, the whole equation of rifle performance is just never revealed.
