Does anyone know the Difference (savage actions)

I've been wondering this a while, but I see that savage "target" actions have 6 model numbers....they are all short action, stainless steel, single shot, with accutrigger and there is "Standard Caliber Bolt Head" and "223 Bolt Head" available. BUT there are 3 model # listings for each type of bolt head, two of which are the same price.
Savage doesn't seem to elaborate, but there must be some difference in the actions if they have different model #s


I'm also curious about the LRPV action, it appears to be fully enclosed, other than the small ejection port, (just like savage's single shot "target" actions) yet it is available with a detachable magazine, similar to savage's "varmint" actions, though the "varmint" actions all appear to have open tops. So is the LRPV action actually a unique action available on Only that one rifle? .. or perhaps it is one of the target actions with an opening milled into the bottom to accept a magazine?

Right bolt right port, right bolt left port, dual port (I think those are it).

the lrpv repeater is one of the target actions with an opening milled into the bottom to accept a magazine
as far as I know they don't sell just the lrpv repeater action (maybe if you call the custom shop?)

Ask and thou shall receive, call and talk to Effie