Here is what I learned and this work every time in 2.5 (to go around eventual buggs that is with the guns) as is now that will be fixed in 2.6 update. First of only guns that work 100% every time and never bugg out stop working is 1 Laser pistol(electric pistol) 2 Electric shootgun and 2 sniperrifle tho sniper have no scoope for now but it work.
To be 100% shore you have guns on you that you chosen make shore you bought them it should say equip, then make shore all is unequiped then leave Arc Corp for this is where you put em on and it will work every time. Why you leave with out them is to get around the gun stop working bug.
Now load back in to Arc Corp go to wepon store, if you have aditional space suit at this point put on one that you don't want to use or take of the one you have if you only have one. at this time equip the guns one at the time DO NOT try them out or any thing else or you might have do do all this over again... just equip.
Ok So now you chosen your guns go an put on the space suit you want to have on and guns should apear on you. Now leave Arc Corp go in to PU (crusader) spawn a ship fly of out side Olisar gunfree safe zone, EVA leave ship or if you are in like a Freelancer just go on to the back and try the guns out. They all should work now, as mentioned above order of guns are 1, 2 or 3, V to holster gun..
One thing you do need to buy to keep them working is amo yes you can pick up free amo at Kareah as some will sugest now, but that is not a guarantied for success-.. :P I go in regularly in store at Olisar and jut buy 3 pack of amo every now and then and it keep the guns working just fine 100% of the time ;)
Hope this give ya a ide what is needed for now, we have some small buggs to battle some time, this make shore guns never bug out on ya..
and as said this will be fixed in 2.6 and all will get alot better :smile:
Cheers :beers: