SR4A is the Anniversary Core Rulebook. Since that's the only book you have, I'll just use it and it alone.
Arsenal changes the choices due to more gun options and the ability to mod firearms. If you're okay with using
Arsenal and other books's stuff, then Umaro's
Archetypes are a must read for anyone new to SR character building and have lots of guns premodded and stated for your use.
Does your group use Stick n Shock rounds? They change firearm evaluations since they replace base damage and AP. From what I can tell, you don't use SnS rounds so I'm going to ignore them.
SR favors BF and FA fire especially if you can reach the RC thresholds of 5 or 8. Therefore you should look at firearms that use BF or FA. Recoil Compensation (RC) is hard to find with the SR4A, but Gas Vent 3 + Shock Pad 1 gets you 4 and that's BF with only -1 die on the second shot. Getting a gyromount cyberlimb accessory puts you a 7 which is just short of 8 for FA fire. But that's an illegal cyberlimb accessory so you may or may not be able to use it.
There are a couple of burst firing pistols that aren't machine pistols. The only one in the main book is the Fubuki, but it's a wonder. A BFing Fubuki does 6P -0 AP versus a heavy pistol's 5P -1 AP base. Since +1 DV is better than -1 AP, the Fubuki is better than any random heavy pistol. Recoil is nearly nil with its built in folding stock which is quite handy. The Warhawk isn't useful since it's SS which means you can't fire twice in a pass (unless you mod or dual wield).
With just SR4A, machine pistols are less concealable Fubukis that have FA fire.
SMG have +1 DV over the Fubuki and the option for FA fire. The best is the HK227 due its oddly restricted but not forbidden sound suppressor. The Ingram Smartgun has a deeper clip, but you can't remove the Gas Vent 2 unless you use the mod rules so the HK227 wins out by being able to get +1 RC. If your GM knows how guns work, he might not let you use a sound suppressor and gas vent together, but that rule doesn't show up till
Arsenal.
