Funny, sorry no references provided, but no issue believing the 1100 yrd drt deer with a .243 set up to do so. According to 6mmbr.com they get 3150+ with 115’s out of them, b.c. .585. Tell me where that hits 1500 FPS in your calculator please? I’m on my phone so can’t run it right now but I already know. Because the .243 set up modern was one I considered a long time. No surprise people have taken them to their limits and proven the math, just like most cartridges. Amazing to me people still want to question the math.
http://www.6mmbr.com/243win.html