Now imagine adding TWO TENTHS of an inch to that 185 TSX, for a plastic tip, and you see where my comment about how potentially unusable a tipped copper bullet can be, if you are running something like a M7 especially.
That 2/10" comes directly out of your powder capacity, and it changes the calculus for the bullet choice some. Would you rather have 200-gn Bullet A at (say) 2700 fps, or 200-gn Bullet B at 2575 fps? With a velocity-challenged cartridge like .358 or .338 Fed, where we are using bullets generally designed for something faster (like a 338 WM or 35 Whelen), these things weigh heavy on the mind <grin>...
That 125 fps should be roughly right btw. Went and looked at my notes just for Rancho. At one time I was trying like hell to get the old 200-gn flat base X bullet to run in my .358. Just going from a 200-gn Hornady to the (longer) 200-gn X bullet cost me almost 100 fps... that's with no boattail nor plastic tip, which would add... gosh... pushing a quarter inch to the length of the bullet.
Can't speak directly to 338 Federal, but the very similar .358 will really teach you some new reloading techniques when it comes to figuring out how to fit the most powder in a case... how compressed a load you can run without pushing the bullet back out... etc. :-)
I think 338 Fed is a way cool cartridge and if I didn't already have a .358, I'd be running one for blacktails. And if ever there were cartridges where cup and core bullets shine, it's fat moderate-speed ones like .338Fed and .358.
IMO and IME...
