I am creating some guns for my map and i wonderd what the max polycount is and how to make it work ingame.

Shouldn't this be in the XSI forum?

Yes it should. The experienced modelers are all there and are more likely to answer you question. I can't even get XSI to run. LOL

Well, to answer your question, there is no "limit" per se, but it's a good idea to keep it with in the recommended guidelines, which are given in the art guide(one of the docs). A little over is not bad, but if it's the main trooper's wepon and there are going to be a lot of them (say 20+ ) on the field at once, try to stick to the lowere end of the guidelines.

The art guide says

Polygon Count Limits (general guidelines):
Props - 0 - 500 polys
Buildings - 200 - 3000 polys (the higher end of this spectrum represents large buildings with large interiors)
Vehicles - 1500 - 2000 polys
Characters - 1500 - 2000 polys

I can't find anything about weapons polycount?
(could be I'm not watching good enough)

well, it should not be more than a character or vehicle. You should follow the Props guileline (500 polys) for your weapons. After all, it kind of is a prop.

Additionally, it depends on what type of weapon it is. If it's a pistol, you'd expect it to have less polies than a big honkin' rocket launcher. It really is a matter of your own discretion.

- and the amount of details you'll put into the model compared to the details you can get from the Texture *moved to XSI forum *

The gun i am working on now is Bobas EE3 and i am planing on giving it exlucivily to Boba. So it will only be one of this guns at the map at the time (if this has anything to do with anything).

And how do i make the gun work with the game?

There's a thread about gun making in the XSI tutorials sticky.

after all a models polycount should depend on the number of geometry-details you need to make it look good. The size of the model (ingame) does not necessarily influence the polycount. Primitive cubes for example consist of 12 polys (tris!), no matter if its a small CD-case or a huge container ingame. Nevertheless the ingame-model-size should affect the texture size. For a CD-case you'd probably use a 32² tex. If its very important for the game you'd use a 512² map because players might have a very close look at it. (you should certainly use mipmaps then). The container will always use at least 512²px (and probably a nice normal map^^), because it will take a lot of space on the screen. Polys will stay at 12 however because both models have the same geometry-detail-level. So a pretty boxy rocket-launcher could even have a lower polycount than a smooth, detailled pistol.
Cylinders or spheres have their own rules of thumb, because of course small cylinders (like muzzles) should have fewer edges than huge pillars. I'd say 16 for a pillar, 8 for a muzzle and 32 for a big cylindrical room/building.

weapons are kinda a waste to put detail into since theyre so small and geometry detail isnt even noticed when mowing down a ton of troopers, people making guns that are over 100 polies are wasting time even.

wtf? i've heard some people play in first person^^ For a 1st person model 500 are ok imho. Depends on the concept of course

well i wasnt thinkin about first person but ive seen alot of wip threads on guns where people put WAY too many polies on a 3rd person gun model and say "WTF?!?!" when all the vertices get all welded together from being too close together and half the polies dont show.

lol - yeah: that seems to happen alot xD

It usually don't screw up the model, but it inverts the polygons so people gets frustrted

it only looks like theyre inverted but the vertices get welded cause the tolerence of them being too close together, you can even set this in XSI when welding, you set the tolerance up and close vertices just weld themselves together and it looks like holes in the mesh, it happened with asajj's face.