I got one on mine, in fact both the 375 and 338 have thumb hole. It gives you a better grip and also helps reduce recoil. Why not a thumb hole stock? After using mostly thumb hole stocks I have a harder time with a regular stocked rifle. My black powder gun is TH.

My wife has a M70 classic in 375H&H with a shortened stock and one mercury insert. I installed a limbsaver pad and 4x loopie scope. The rifle weighs 8.5lb with three rounds in it and she lobs 300gr rhinos down range without flinching.
I should add that she is 5'4" and weighs 115 soaking wet. Very recoil sensitive as well, but she says this recoils only a bit more than her 308. I've shot it extensively and figure about 30lb felt recoil. We don't lighten the load either. Those 300 grainers are going 2500 fps.

I have loaded my 375s down too 2400 and the recoil is slight. I think the very best bullet for this is the 300 gr WDLY.
On a larger bore... I have a 404 Jeff but unlike many posters on here, I shoot mine at 2150. I think a man would would be hard pressed to find it lacking, I cant tell the diff erence on game between it and my lott at 2150.

DOJ,

OK on all of what you said - BUT - do you really want a thumbhole stock for a DGR? I'm thinking- No.

The rifle at the bottom of this picture is a Model 70 375 H&H, originally owned by Abby Burns of Wichita Falls, TX, who used it to take 3 lions, 2 leopards, a black rhino and 4 elephant (the largest 72/87lbs) on one safari with Terry Irwin. She was small in stature and made several modifications to enable her to shoot it comfortably: 2 mercury tubes in the butt, a muzzle brake and a shortened stock with recoil pad.

Savage 116 in 375 H & H, has a off/on brake. Re stock with a MPI thumb hole stock made of composite material. Feels like about 308 or 7mm 08. It will shoot also, very small groups. Very nice to carry. It won't break your bank.

A .376 Steyr in a Mauser bolt action with a 24" barrel with my handloads of 300-grain Woodleigh SP Protected Points loaded to 2400 fps (I got 2320 fps out of my Steyr Scout's 19" barrel). The .376 Steyr seems to have less recoil than the H&H, even when pushing the same weight bullet at the same velocity, perhaps because it's more efficient and uses less powder to do the job.

Jeffeosso, HunterJim, and others can attest to the .376 Steyr's lower recoil as well.

Anywhere you hunt with me she can use a 9.3x62, We even have one in camp for the ladies, older men and youngsters in Tanzania if we are advised ahead of time...There will be no problem...and it recoils a lot less than a 375 and certainly kills as well....Just for what its worth, the caliber laws are not inforced and you have a PH with a heavy right beside you...

My experience is that the 270gr bullets subjectively recoil more than the 300gr bullets. I believe that this has to do with the velocity of the recoil not the ftlbs of the recoil. I would recommend shooting 300gr bullets and reload to 2400 fps.

Alternatively, go with the 404Jeff with 400 gr bullets loaded 2100 to 2200 fps. The original loading was 2125 for 400 gr bullet according to Cartridges of the World. It developed quite a following with that loading. I believe it will fit a Mod 70 Win, and know it will fit a Mauser. Ku-dude

George Caswell has outfitted several ladies for DG hunts and he suggests the 404 as best bang with least recoil in the DG calibers.

Any calibre you like. The key is a mercury recoil arrestor in the stock.....alternatively Blaser make a tungsten bead version which although slightly larger is even more effective.

I've got a mercury tube in my .500 and it's a pussycat....

I'd go h&h,with a 270gr premium bullet,or a browning BLR in 450 marlin with a 400gr swift @2100fps,would make a great buff rifle for your lady!

I think that the caliber recomendations here have all been sound I'd just like to add that in addition to the decelerator pad throw a cheek ease pad on the stock it really does wonders for felt recoil.