No question they have a stand/rest setup so there is no way a finger or hand twitch will move it off target. It might even be a hands-free job that eliminates all human error.
Did you test your accuracy from a rest or just free hand?
Blame will always fall on shooter first. Were your misses grouped or all over the place? Are your other guns single action or shorter trigger pull?
Good groups point to barrel or sight issues, spray pattern points to shooter generally.