Sorry for the lack of updates, I've been watching other shows and there's hasn't been much knife content on NCIS.
Abby is acting like Ziva to mess with McGee
Season 5 Episode 18 "Judgment Day" (04:24):
lol i have that knife and love it and in fact i just did a review of it
http://www.canadianwildernesssurvival.com/reviews/Reviews/BLACKHAWK MOD C.Q.D Mark 1 Review.html