John
this is the RWS info
https://rws-ammunition.com/en/products/centerfire-rifle-cartridges/rws-375-hh-mag-uni-classic-19-5g
Velocity 2560fps at the muzzle for the 300gn TUGS.
With a zero of 100m it drops 15,5cm or just over 6"at 200m - that's pretty damn flat for a big slug
BC = .334

I've compared the 9.3x64
its BC = .465 for the 293gn TUG
https://rws-ammunition.com/en/products/c...94cb81021e61c72

Both of these loads have been lowered somewhat compared to an old RWS catalogue I have.
My original RWS loads were chronographed at 2640fps for my 26" barrel so these new loads are much more conservative
The BC for the 375H&H seems far lower than the 9.3 which doesn't seem right are they are virtually identical cartridges ballistically.

Sorry to Hijack this thread, just trying to point out that the owner of this magnificent rifle has obviously designed it for plains game, even buffalo if need be!
great choice in ammo to regulate it with!