Kudos to the community! Just when I've given up hope to get any answer, I got a full build plus rotation and additional advice. I've taken all your input and came up with this build. I swapped Pinning Fire for Custom Enviro Suit, and Advanced Targeting for Integrated Cardio Package. I erased Med Tech completley, because I'll trust Mako to do the healing.

Hello guys, as I've already mentioned in the title I am in dire need of an arsenal pve build. My main is a juggernaut 50 and atm the main tank of my guild. I have several alts, all at lvl 22 right after finishing the first world after faction capital (Balmorra/Taris). I've taken a pause some time after 1.2 hit due to guild inactivity and discontent of some of the changes. But my break was from playing the game only, not getting info. So why a arsenal merc, the got nerfed you know? Yeah but the simple answer is from all my alts it is the only toon which story and flair momentarily pleases me. I even got a Sentinel the fotm. But the Jedi Knight story is really dull. I mean really, take out a super weapon and then finish the Emperor. Luke would say. Been there done that -.-. Won't play a marauder, because I've experienced the Warrior story. I started a madness sin (only class who was untouched by the nerfhammer this time), but Inquisitors story is not my taste. So I went back to my merc. Last time I've played him he was 20ish and the gameplay has just only become like this. So what I need is a good build, and maybe some rotation help to get from 20 to 50. What doesn't matter to me is that it has to be competitive, because my guild is in such a decline that by the time I can raid with this toon 1.3, a buff or whatever has already happened. TL;DR Need pve arsenal merc build from 20 to 50. And no don't wanna reroll, respec. No desire for merc pyro, pyrotec. And no shield specialist. already got a tank.