for background i should mention that i have a character who is a full convertion borg basically. every limb including head and torso are obvious cyberlimbs. aside from the toughness that comes with that he fills the role of hacker/engineer for the group.

since he only has 1 IP(ran out of money and essence in char gen) i was thinking about stuffing in an external weapon mount on a shoulder for additional contribution in a firefight. i figured it would be a great way to sort of have a few extra IP's worth of action(mount acting as a drone) and something to keep my body protected when hacking in full VR.

the problem is when thinking about it i started to wonder...just how big is this thing? would i be wandering around with a completely obvious submachine gun on a 16F mount all the time(earning a free ride to jail or a bunch of free bullets from the star)? i was thinking for the high capacity cost of 7 a good deal of it may be below the surface. since it doesnt say i figured i would ask you guys, do you think the mount its self is small enough to remove the weapon and have it seem like part of the shoulder when not on a run? how abut having it retractable? it would almost certainly add capacity but it is already 7...

what is your opinion/ruling on the matter?

This seems to indicate that they are... bulky, and thus not easily hidden. You might be able to pretend you have a hunch on your shoulder or something, but I'd imagine it isn't going to be something you can hide easily even without the gun in it. Remember that among other things the mount has to be able to hold the gun somehow (Thus requiring a clamp or something similar) and it has to have some freedom of movement (It has a 15 degree firing arc) and so has to have room for a gyro and whatever else a moving mount requires.

Hmm... actually it might not be all that obvious, I could see most of that being inside the arm or able to be retracted/folded into the arm when not in use.

Ah, i remember that in third edition a torso could hold an extandable/folded arm with a HOLY CRAP light machine gun... weird... but we had one character with that. Was not that bad since it took all capacity.

Charted on page 42 and discussed on page 43 of Augmentation. Look for External Mount.