I shot two deer in the last week with the Sierra 140 gr SBT gameking out of my 6.5WSM at 3200 fps. The ranges were 175 and 154 yds respectively. The 175 yd doe was quartering away and the bullet cleared out a six inch section of ribs going in, angled through the lungs and top of the heart and penetrated to the opposite shoulder where it splintered the bone. I never recovered the bullet, however.
The 154 yd buck was shot behind the shoulder, the bullet taking out a rib going in and coming out. I am satisfied with the performance of this bullet for deer but I would probably not use it on elk. I would instead use something like the GS you are shooting or a partition, or the gold standard for moderate range performance seems to be the Barnes TSX.
I shot my bull elk this year at 320 yds with a 225 gr Accubond out of my 338 RUM at 3050 fps. It hit and shattered the offside shoulder bone but did not exit, nor did a followup shot that passed through the neck into the chest. Elk are big creatures and I certainly wouldn't want to shoot one with a SMK out of a round like the 6.5 Swede. I would also be willing to sacrifice a little accuracy for a tougher bullet. You aren't going to be airing it out at 500 yds on an elk with the swede.
Just my thoughts, hope this helps.
The critters have to win every time, I only have to win once.
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