While I haven't tested those exact pellets for Hard Air Magazine, I will state that I have never tested a pellet that exactly hits the advertised weight, and they ALL have a range of weights.The range is wider on some types of pellets than others. Head sizes and lengths are also variable. Here's an example:https://hardairmagazine.com/reviews/hn-baracuda-match-10-65-grain-177-caliber-pellet-test-review/
I have not bothered to weigh them but over the years they have been one of the best .22 pellets I’ve used. Most rifles group them exceedingly well. Here lately I’ve been using them in the DAR and it is on a 24/24 run on small game and pests between 40-60 yards, the smallest targets being chipmunks and house sparrows.
My experience has been very similar in the 16 and 18 gr size versus their JSB counterpart.