I can attest to Mike 375's reduced loads with the Hornady 220gr FP which he kindly passed on to me. Its a beauty!!!

Does 2200fps out of my 24inch barrelled Sako as measured by the CED Millenium chronograph & sub MOA accuracy at 100m. So bloody pleasant to shoot, I had about 40 rounds & we finished them off in minutes between 3 of us shooting offhand. Can't say that for normal 375 H&H loads. Blast is also at a very low pitch, almost like a black powder round.

My load is 42.0gr of AR 2205 with Win cases & WLR primers. Cases neck sized only & bullet seated to cannelure but not crimped. Load also happens to be dead on at 100m when my POI for my 270gr Woodleigh (Full Power) load is 2.5 inches at 100m. So no change in scope setting. Great luck.

Mike you worked out some loads for your twin 378 Weatherby's yet? May be able to try those reduced a couple of grains for my 375RUM which is a brute with full power loads.

Hornady makes a .375 bullet in 220 grains for the .375 Win case and another in 225 grains for the .376 Steyr case

loads for either of them reduced are as follows.....from the Hornady handbook.
SR 4759 42 grains.........2,300'/sec
H 4227 38.1 grains........2,100'/sec
AA 5744 47.7 grains......2,300'/sec

At that velocity I'd prefer the 220 grain flat nose for the .375 Winchester.

Given the weight of most .375s I'd estimate recoil to be similar to the old .30-30