I have an ar-10 in 338 fed; just too heavy; road huntinggun. I killed a couple moose over the years with the 338 fed; 210 nosler partition. Moose would do the 3 step shuffle and drop.
I knew some Indians that shot a sow polar bear with 556 ar; saw the picts.
You must have a heavy 338 fed barrel set up. Mine is 18” with a KAK can on the end. I just weighted without the lower my 308 20” and my 338 w/o the KAK on it. The 338 is only 500 grams heavier both with the bolt and charging handle. My 338 is a stainless socom contour the 308 is also stainless but a fluted HB socom neither is too heavy to shoot and skoot with I got the 338 specifically for on the ground feral hog hunts where trees are too small to climb. I prefer 25+1x 338fed with A-Frames vs 10+1 of 458 socom in the 12.5” AR15 set up I have too. That now gets saved for subsonic duty only with 500gr @ 1000 fps is greater than 250 gr at the same velocity plus the 458 is overgassed and will.cycle with subsonic I wouldn’t even try with a rifle length gas system in the 338 it’s not worth the heartache.
“I knew some Indians that shot a sow polar bear with 556 ar; saw the picts.”
I read a story about an elder Inupiat woman in Point Hope, Alaska who was jumped from behind by a polar bear when she was walking to a friends house during a January blizzard. The bear had her face down, flipped her over, and she balled up her fist and shoved her fur mitten deep into the bears throat and released. The bear choked to death. Now THAT is a survival story! Hope she got her mitten back...