Yes, the Mav/Hornet/Trracer all share a barrel thread that is different from any other marker. If you want to find a barrel see the second post in ACI Faq. And as far as i know, Smart Parts hasn't made a barrel that will fit it.
I wish ACI would create a barrel adaptor
See this thread of a few barrel's
http://www.pbreview.com/forums/showt...hreadid=172579