Choosing a long range caliber

[STGguy]

By the time you pay to have a 700 action completely trued you will be at the same price as a custom, and if you chose to sell it you will recoup most of your money. The splash signature from a 338 vs 300 is undeniably much better at distance (over a mile). That would be the greatest factor in choosing between the 2.
6.5 is not a mile caliber.

Amen, I've shot my 260 Rem bolt rifle that is a tack driver and amazing out to 1000- 1200 yds a few times at a mile up where I shoot in in NC Mountains and 100% agree w this.
Only in the case of a direct hit - for me the gong was too little so I shot a bigger rock - and spotting impact - even in dirt is very frustrating.
I was shooting w a guy who wasted 20-25 rounds of 308 w no hits and I got prob 3-4 hits on big rock , no idea where other shots were.
Got me a 338 LM since , lots O Splash !