I'm in a 2E Dark Heresy Campaign, and we've really only just started. I'm playing what is essentially a Kasrkin (because I love them) and I built him as a warrior. He's got decent stats, the only thing preventing him from shining is my inability to roll low. I need some help with my character build going forward.
Here are a few things that I'm planning to make the character shoot better:
Mind Impulse Unit with weapon interfaces for hotshot and laspistol
Motion predictor for Hotshot
red dot laser scope for hotshot and laspistol
Backpack ammo supply for hotshot
The character was supposed to be an all around combat specialist, but I need some help with traits and such to make him better. I'm thinking of taking marksman, to keep from incurring penalties for range.
I need a bit of help.
I'll try my hand at this, since I'm running a campaign, but first: I don't think the MIU with Weapon Interface is supposed to work that way, I believe it's more for operating your weapon without actually holding it, like Predator's shoulder-mounted plasma projector thing. You may want to okay it with your GM before you go looking for that particular piece of kit, and keep in mind that it has to be of Good quality before it provides bonuses.
Aside from the MIU, your planned weapon mods grant: +10 bonus for single shot attacks, +10 for Semi-Auto Burst and Full-Auto Burst.
Now, you said you were planning on taking Marksman, which has a pre-req of BS 35, so I'll just go ahead and work off of that.
A Standard Attack (single shot) provides a +10 bonus by itself, Semi-Auto Burst +0, and Full Auto -10.
So you come out to...
Single Shot: 55% chance of success
Semi-auto: 45% chance of success
Full-auto: 35% chance of success
Now we throw in Aiming as a half-action, which is a further +10 and allows you to attack once every round (You can take a full turn if, say, you're sitting in ambush, or something, for +20).
Single Shot: 65%
Now comes Range, which ties in with your thinking about taking the Marksman talent.
The range of a Hot-shot Lasgun is 60m, so Short Range is 30m, Long Range 120m, and Extreme Range 180m, so you should ask yourself "How often am I going to be fighting things at distances of 120+ meters?" If the answer is "probably not very often," then maybe just grabbing a longer ranged secondary weapon (like a long-las) for situations where you can plan ahead might be a better idea.
Short Range, meanwhile, gives you a further +10 bonus, and Point Blank (flat 3m for all ranged weapons) gives +30, so measure those distances!
For further help with HITTING (most ranged weapon talents help with damage and penetration), I recommend two more mods: Modified Stock and Custom Grip, the Stock gives an additional +2 BS for every half-turn spent Aiming (every bit helps, right?) and the Custom Grip gives you a flat +5 to all BS attacks with the weapon.
As it stands right now, I'm hoping that your BS is higher than 35, but even if it is 35 you're already sitting at 55% for a single, aimed shot, which is pretty good for a beginner character.
Before I start throwing around talents and such, I have to ask, what's your group dynamic like? Are you the sole heavy hitter of the group? If the enemy comes running and you have to fix bayonets and get up to your elbows in their guts, is anyone besides you expecting to get out alive? And further, what do YOU want to be? Good with a knife, better with a gun, or straight-up shooter? The new edition is really free with what you can do, so knowing what you want to be, what you might need to be, what your combat stats are, and what your Aptitudes are can help narrow it down.