Having a negligible effect seems reasonable, at least for the unlocking: as I understand it, unlocking is primarily a rotational motion/operation, which some extra mass in the buffer would not have any impact on. As for rearward motion, seems possible that an increase of ounces compared with the thousands ksi pressure acting upon it (the cross sectional area being the same) so the force/acceleration, F=m*a, might get slowed a bit by having to accelerate a heavier mass... but it could also be a negligible impact. I haven't run any numbers personally, but it doesn't defy logic either.
edit to add.
I went back to listen to the video, it started for me (in the link) about 14:00 into the run. His discussion revealed a couple things that might have a bearing on this discussion here, as what I would call clarifications.
1. His discussion of bolts and buffers in this part of the vid seems to revolve around shooting suppressed/unsuppr., as well as he mentions that some might be using "boutique" really heavy buffers (beyond the H1-H3 range) -- of which boutiques I don't have any knowledge-- as compared to H1-H3 buffers. In discussing bolt movement, he says a heavier buffer (implying mostly the H1-H3 range) will slow down buffer movement and make it run "smoother" - a rather unscientific term imo, but probably referring to a more or less lack of "crashing" into the back of the buffer track at the end of the rearward movement... He does also say that there is a delay in buffer opening, but it is of the order of 0.5-1.0 millisec, which to him was a negligible timeframe.
2. I didn't see parts where any graphics of bolt motion or high-speed vid segments, so I'll leave that discussion to others. Maybe those were at a different point in the vid.
This all may or may not impact our discussion here, but for someone shooting only unsuppressed, and thinking of whether to use carbine, H1, 2, or 3, the "slower opening" may not be perceptible but a slower buffer velocity and "not-so-crashing-into" the far back travel stop, may be perceptible, and useful. Any "slowing" of the opening cycle is probably not detectable to the avg user.
edit to add.
I went back to listen to the video, it started for me (in the link) about 14:00 into the run. His discussion revealed a couple things that might have a bearing on this discussion here, as what I would call clarifications.
1. His discussion of bolts and buffers in this part of the vid seems to revolve around shooting suppressed/unsuppr., as well as he mentions that some might be using "boutique" really heavy buffers (beyond the H1-H3 range) -- of which boutiques I don't have any knowledge-- as compared to H1-H3 buffers. In discussing bolt movement, he says a heavier buffer (implying mostly the H1-H3 range) will slow down buffer movement and make it run "smoother" - a rather unscientific term imo, but probably referring to a more or less lack of "crashing" into the back of the buffer track at the end of the rearward movement... He does also say that there is a delay in buffer opening, but it is of the order of 0.5-1.0 millisec, which to him was a negligible timeframe.
2. I didn't see parts where any graphics of bolt motion or high-speed vid segments, so I'll leave that discussion to others. Maybe those were at a different point in the vid.
This all may or may not impact our discussion here, but for someone shooting only unsuppressed, and thinking of whether to use carbine, H1, 2, or 3, the "slower opening" may not be perceptible but a slower buffer velocity and "not-so-crashing-into" the far back travel stop, may be perceptible, and useful. Any "slowing" of the opening cycle is probably not detectable to the avg user.
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