Couple of questions:
What main things to look for?If it's a homebuild I would say walk away. I have not heard anything bad about the factory-made weapons. But if all you can find is a home built one then check the rivets both externally and internally. Make sure the receiver box is square. Check for excessive wear on the trunnion feedway. Check the internals for proper machineing. The trigger frame ears like to snap off with improper machine work. Check for damage to the backplate grooves
Any manufactures / builders to either look for, or steer away from?I no longer know the players in the game so a little more research would be good. Check on
M1919A4 forumsAre most of the semi's converted military full auto ones?All of the live weapons are converted from mostly 1919s that Israel returned. You will find people selling USGI kits for a premium but all that means is that it never went to Israel. Not worth a premium IMHO.
The ride side plate is the SN part correct, and that's what's often referenced as to what the history of the build is.Yes, the right side plate is the controlled part. However it can be hard to tell who made it (semi-auto version) as many are made with replica markings. When I bought my RSP I was able to choose the manufacturer.
Is only a different barrel needed to go from 30/06 to .308?For 30.06 you need a barrel and booster. 7.62 is the same (barrel and booster). However, a 30/06 bolt will not work with 7.62. A 7.62 bolt WILL work with 30.06. You can also get kits to run 8mm, 7.62x54r and 7.62x39.
What's a good price range for a good version - 2 for a bargain, 5 tops for a really nice one with all the accessories?Last I saw a gun only was around $2500. Tripods are still around for $300ish with T&E and pintle. The most expensive accessory is a belt loader which cost as much as the gun nowadays. Barrels are anywhere from $100-$300 depending on caliber.