I have been off deer hunting in KS for the past week so I missed the last part of the discussion on this thread............ no KS deer pics, did not see any big ones :(
First of all, to ccsykes.......... sorry we hijacked your thread, but it looked like Kirby got your questions answered before we went off on a tangent!
Lapua Guy, You are new to this site and may have made some assumptions about the shooters on this site that are not entirely accurate, and we may have done the same with you. I'm not going to get into the who made what military "kill" for two simple reasons....... first I don't really follow the military side of "long range" that closely so I have little knowlege of such other than what I occasionaly watch on the military channel.......... second, it has no bearing on the comparison of 338 Lapua and 338/378 or 338 "KUBLA KHAN".
First, a belated welcome to the site and I hope you find it as usefull as I have over the past several years.
I think your biggest mistaken assumption is that most on this site shoot factory ammunition, with factory rifles. There are guys on this site at all levels, some do shoot factory stuff and thats great, but most of us who are shooting at longer ranges 800 to 1000 and longer are at minimum handloading and most have custom or modified rifles with optics suitible for the ranges we are shooting. At first I did not even realize you were trying to make your comparison using factory 300 grain Lapua ammo and factory 338/378 wby ammo with whatever 250 grain bullet they load. That is not a valid comparison in any way. As others have said, when you load a 300 grain SMK or 300 grain Lapua Scenar in both, the 338/378 will push the 300 grain bullet about 200 fps faster than the Lapua. When handloading, the same bullets, powders, and primers are available regardless of which one you are loading for.
So, that is what led me to challenge your statement that the 338 Lapua shoots flatter than a 338/378. Myself and others on this site are not looking at "factory" loads, we are looking at the maximum performance of both cartridges, and by that measure the 338/378 is a faster more powerfull round than the Lapua.
Final thing...... "KUBLA KHAN" "KAHN" "KHAN" I think your assumption that I simply don't know what I am talking about or that I don't own one is a little presumptuous based on a different spelling. I have seen it spelled "kahn" and "khan" and I commonly transpose the "a" and the "h". I will grant you that I think the correct spelling is "KHAN". However, as you will see from the attached pics Kirby Allen (Fiftydriver) spells it "KAHN" and that is good enough for me.