You shouldn't HAVE to fire.....
You shouldn't HAVE to dry fire a 686. Their calling card is a very sweet trigger both in SA and DA. HOWEVER, some of the ones they are throwing out now due to the shortage may have gritty triggers, but either it will smooth out or S&W will fix if it is a warranty thing. I do find the 6" to be a little nose heavy, but being a range gun and having Pachmahr grips that I like on it, it feels great to shoot. I'm just a little prejudiced maybe, but if I lost my 686 I wouldn't rest until I found another.