OzFclass

Tony, I hope you can see more with the naked eye than is revealed in those photos. Its very difficult to make out anything meaningful.

Maybe I will have to get my own borescope and try focussing it ...

I would love to know what makes a barrel good or dud... Savage factory barrels are rough as guts but a few still shoot well anyways. I had a 223 that was super accurate but a 7 twist and blew up noslers, but not other brands. From which i surmised the factory barrel was scoring the jackets and noslers had thin jackets, bad combination. Sierras shot a treat !

The way that truflight behaved i also suspected some stresses that caused movement as the barrel heated giving elevations, but at that stage my elevation issues could easily have been caused by bag setup hence i was unsure. My setup has improved but i am still confused by all this .....

I am a work at the abattoir at the minute, but tomorrow i will get you a couple of "comparative" photos of one of the other "clean" lands , as well as draw some explanatory lines on the two photos above and see ifi can make it a bit clearer for you.
At 250 power like the first photo is (25 x bores cope through a 10 x digital zoom camera) and held close to the land, it easy to distort the vision