I can confirm that on the LRBT bullets. I have been shooting them for a while, about 500 now in testing the 375 SOE rifle. It's the 408 CheyTac case (using TTI brass) necked down to 375. At 3100 fps ( a little on the slow side, but it saves barrels ) it has a supersonic range of 2900 yards, which is 400 yards past Barretts claims of 2500 yards, in a barrel killing combination.
The 375 LRBT bullet is the slickest bullet around. Yes, that are on the expensive side for now, but if you want supreme performance, check them out. There is no comparsion. Ignore the statements you'll hear about needed special barrels and twists, it's truely irrelevant becuase if you're building one of these hotrods, it's ALL special, and you're not likely to shoot 50 rounds in a session, well maybe you are. I've built some of these, here is a link to my website with some research on teh 375 and a couple of pics of some rifles.
I really push these bullets becuase there is no comparison, their BC claims on their website is actually lower in most cases than the true BC value over the supersonic range. There have been claims of a lack of accuracy, but that is usually attibuted to the rifles and barrel combinations. You cannot swedge these bullets down a barrel like you can a jacketed bullet, you can engrave them to spin them correctly, but you can't squeeze them. Then they become inaccurate.
Sniping Operations Executive Home Page
SOE 375 Web Page