According to the recoil calculator in link below the 20 lbs 110 BA with a 300 gr bullet pushed to 2900 fps by 93 gr of powder would produce about 24.5 ft*lbs of recoil energy.
http://handloads.com/calc/recoil.asp

That puts it at about the same recoil as my 12 gauge slug gun. Now I can shoot that gun all day long at the bench. But my shoulder will be a little sour. Not quite enough to flinch though.
I have never tried to shot my slugger in prone position.
But it's supposed to punch a bit more that way.

So similar to my slug gun. Than add the shrouded brake, the piston recoil buffer tube, and a good thick recoil pad and I should be pretty much okay. (fingers crossed)
I don't think the .338 LM is the kind of gun I will shoot 100-200 rounds per range visit like I do with the slugger or the trap shotgun. So hopefully it won't be too bad.