I’m not sure I think there is any cartridge out there which a shooter would consider still living past 10,000 rounds, being the same shooter which would think any barrel would be burned out by 1,000 with any cartridge. We hear guys talking about 5.56’s and 308’s with 10k+ cartridges, but these are guys blasting extreme round counts with little demand for precision. When we see those same cartridges being used by precision shooters, suddenly the claimed barrel life changes and we’re talking about replacing barrels by 4000-5000 rounds. So the blasting guys really aren’t great indicators of how long a barrel should last - it’s kinda like the difference between the guy with a pickup with 400k miles on it (being a guy who made 442k on one of mine, and 380k on another), but has replaced the transmission, is sitting on a wool blanket because the seat fabric has totally worn away, there’s a pair of vise grips replacing the driver’s side window crank handle, and has to pour in a quart of oil every time they fill the gas tank… “still driving” isn’t really the same thing as “like new.” So you have to calibrate what are your expectations for a barrel - if you’re shooting small groups, I’d run a borescope through it and examine the fire cracking and leade condition. If you’re just blasting, or wanting to plink around and do a little hunting, then maybe it’s worth considering.
Also, $100 off retail might mean very, very different things - as some barrels are $100, some are $1000. I assume we’re talking about a higher priced barrel, but since it’s a Savage, I’m wondering if it would have been somewhere around $400-450 new? If so, then a barrel with decent life left at $300-350 might be well worth that price.
I’m not certain I believe there is a 6mm cartridge on the market which makes it past 5,000 without slipping in velocity and group size. I’m only running 2815fps in my Dasher and still changing barrels at 2500 rounds, as the velocity becomes unreliable. But again, running a borescope down it would tell you all you need to know as to whether it is way over 100rnds or not.
I have bought a couple of barrels from other competitors which were ~100-150 rounds down the tube. It’s not so uncommon that we buy two barrels at a time and break both of them in, so one is ready to go when the other falls off, rather than trying to do new load work up and break in during the middle of season. But then if a guy decides to shoot a different cartridge and still has one of those “new, but broken in” barrels waiting in the wings, they sell it off. It’s like new, so it deserves a good price, and doesn’t even come with the burden of break in or load development…
So it would be nice to know more specifics - what barrel, what was its purchase price new (or what would be its new price), and what cartridge? What is the claimed reason for selling the barrel rather than making use of it?
Or, just run a borescope through it and eliminate any speculation.