Oh yeah, one more thing. Once you get a real gun guy worked in, one who knows how to suppress his weapons; you may also want to think about optics. Something along the lines of a 4-12x44 variable power scope atop a bolt action rifle in .308 or maybe a big high end scope sitting atop a Barrett in .50 caliber. You know, something that can reach out and touch someone (or somezombie) from a distance - "because long distance is the next best thing"! Picture it like this, the group takes the high ground, scopes out an area they want to enter, see some flesh eating zomboids in the distance and have their sharpshooter take aim and whack a dozen of them, with his high power and scoped rifle, before they move into the area. Sure you are gonna make sure there are more zombie surprises waiting for them on which they can use swords, bats, axes, crossbows and close in guns - even silenced ones.
Oh yeah, if you are in need of a firearms instructor and weapons consultant, I am available.
All the best,