I was attempting to find the lands for a new load. Accuracy went bad with the old one and of course you can't get the 208 amax (300 win mag, lost count on rounds) anymore. Long story short it appears that my barrel maybe toast. Am I looking at this correct. No land marks, just a solid circle.
My gut instinct is that you have a nasty carbon ring in the throat, though it seems a little far forward perhaps.
Search the forum for "carbon ring" if you're not familiar with the concept. There's reams of information on what they are, what causes them, how to get rid of them, and how to prevent them. In short, they are a buildup of carbon in the throat, which will constrict the bullet as it transition from the case to the rifling.
Some more info would help. Estimated round count? Was the gun fired hot lots of times (rapid strings of more than 3 or 4 rounds)? Do you thoroughly clean it often?
Unless you're hammering away with hot loads, a 300WM ought to last 1000 rounds or more, and even if the throat is toast, that just means the rifling has moved forward, making the throat longer, not smaller. You'd still have a tube that's bigger than the bullet, until it engages the rifling somewhere, so I doubt that's your problem.
Lastly, the Hornady ELD-M series of bullets has worked as well or better than the A-MAX for me in every gun I've switched over from the AMAX (7mm, 308, and 556).
