Any shotgun with hi rate of fire, shockwave is best but rare,on level 30 thru 60 I always had an electronic gun, Sunfire, or sunburst, something like that, was a go to gun cause it had decent dmg + rate of fire. In fact it doesn't really matter except whatever your preference might be, for me I put dmg, rate of fire, reload paid a bigger price in my opinion, if I didn't have a weapon that would relatively boost in those characteristics, I. Wouldn't keep it. I modded all my weapons to their highest abilities and got rid of what didn't work. It depends on your class too, ripping and running gung ho, can get boring, I finesse the game when I play solo, certain maps for xp others... well, really for whatever ineeded, now playing with other people, it was easier to let someone do the ripping and running, I would clean up. Each map is only...what 1:30 to play 3:00 minutes? If you play with others different guns for different maps......solo.....have the top of weaponry. I had a set of values. Fire rate below 8, probably didn't last too long, I couldn't upgrade , that probably didn't last to long either , whatever suits you. By the way, it doesn't get any easier, zombos skills grow just as yours do, that's why I am a medic, gas bomb does 50% reduction, that's huge when your fighting by yourself.
I am a lvl 86 medic, and I earned every level starting from one it's taken .....close to two years, I'd say, but the medics don't have opportunity to heal the rest for the first 20 levels....period. they don't have enough points per level to go around. Between trying to beef up there own skills, they've got separate medic skills and only working with one point per level is stretching too thin. I could buf medic skills but then I short myself to character skills. . I want to regenerate my health, I want to shorten the time i spend knocked out and to make a viable med kit even worth tossing out to assist somebody, your going to invest at least 5 to 10 points if you are a heavy, are you sacrificinghalf of the points you make for the rest of the team plus and this is needed, , what would really help if there were comms in the game where a four man team could be alotmore teamcentric. As it is, Everytime I play on a survivors map, there's always one guy who just goes and opens doors, doesn't wait for his. Teammates just let's loose all the zombies and I promise you if your not seriously modded out up to date on gear, you are gonna die so it's little things mostly if somebody chats "I need help" I automatically stop where I am and go assist, always Everytime. So give the medics a little. Break cause they are just trying to get to the next level where they can afford to buf them skills so they can assist. Of course bad hombres are every where hope to see you you on a map. .