Cost ineffective to issue Big Army 338's at their skill set. That is a Ferrari and not a Ford Escort. With the 300 Win Mag they at least got a Mustang- if CDR's let it out of the garage to run.
The biggest factor in the Army are not material solutions- they are mental mindset zero risk factors, understanding training and capability.
You still have CDR's who do not understand Snipers, do not trust snipers to operate, and lock their long guns away turning the Snipers into Personal Security Detachments for Colonels and Sergeant Majors with entourages to follow them around like they are Rock Stars with ego's to boot!!! They are sipping a little too much of their own Kool Aid.
The Sniper's "sticks" ended up under lock and key never to be used.
Giving Big Army Infantry / Scouts 338 Formula 1 $$$ sticks is a complete waste of money. Like I said the problem is not materials- it is mental.
There is a movie in the 80's called the "Pentagon Wars" that illustrates my point exactly related to Big Army's Agile process on development and who is making the decisions.
If you are looking in a certain rifle weight portable, recoil factor, range- BC- FPS, target factors, surgical application, the answer is 338 - within certain tolerances and extensive training / resources.
If you are looking at a cost efficient standpoint- aka "on the cheap", currently a 300 Win Mag for Conventional Snipers at current doctrine levels and ammo grades will work.
I would have personally liked a 7mm mag for lower recoil at a high BC shooting Bergers.