I have the 270wsm at 21.67 inches. Running 150 NBT at 3095. AR2217. When they run out I'll go to eldx. I wouldn't go any shorter. Suppress it and it doesn't kick too bad. I load to mag length, no issues. It does everything I've thrown at it so far. Vx5 on top it's a good reasonably light all rounder.
Not sure about the 300wsm, but I know of a winmag and it's a dog. Maybe too light for the caliber especially at 26 inches.
I also have the 708 running 150 eldx. Not sure the wsm has much advantage especially if you're ranging and dialing but I like the xbolt more than the cheap r700 that groups about 2 of 3 inches after I took it hunting in the rain for a while and let the rot set in.
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