Thanks, that spurs another question. all the Picatinny rails I found that will fit my rifle (Long action, flat back model) are listed as "20 MOA lift" Does this correspond to a specific height (I assume it does) or is the rail actually machined with an angular departure from the bore (I would assume not)?

My optic has a 44mm objective and I want to keep it as low as possible for the obvious reasons. I switched from a 50 mm optic recently so my goal is to drop it down by about 1/4" (which would mean a roughly 1.5" centerline height vs the current 1.75"). It's always hard with mail order items to figure out if they'll give the right scope height, but based on what I have now I was assuming I'd need a low mount rail and either low or med height rings. That's just a seat of the pants guesstimate though. Am I missing an easy way to determine the mounting height of the bases and rings?

Sorry, if it sounds like a dumb question. For the most part once I get a rifle set up the way I want it, it stays that way forever, so I don't get much practice when it comes to shopping for small parts.