Thanks for your reply.
Neither of those two videos in my original post using a sling. You can skip most of the video just go to the specific time I mentioned and see what I was asking.
I believe loading the bipod will help on recoil/make the rifle more steady after pull the trigger.
Mark (in the 1st video from at about 10:10) said even in his 338LM, he can control the recoil effectively and the reticle only moves within 2MOA without a sling.
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