I'm looking to spray new gelcoat on the bottom of my boat and i'm looking for some suggestions on a spray gun that works well and is economical. Since i can't flip my boat over i'll be doing it from the bottom also. Any suggestions anyone?

I use a binks 2001. They are affordable and work fine. Can be picked up used pretty cheap.

There is an actual gel coat dump gun:

http://www.shopmaninc.com/equipment.html

But being that you are doing the bottom, it may be easier to roll since you would be spraying up anyhow. I don't that that gun in the link would even work for you, now that I think about it. You'll have to wet sand and buff either way, at least with rolling it you won't have to deal with overspray.

I have that gun and it works great but its almost impossible to spray upside down. You can get away with just about any mid priced gravity feed gun just make sure you have a monster tip in it and use Duratec to cut the gel.

Here are a couple of choices for gelcoat spray guns.

If you end up with an automotive type gun get a 2mm tip minimum. I use a 2.2 on a Devilbiss GTI, works decent but only when used with Duratec gloss additive.

If i decide to roll it on instead, what kind of roller is reccomended?

When your done with a roller job people are going to say look he did that with a roller.

I wasn't sure that's why I thought i'd ask.

Black foam roller!,,if you want it to look good i would spray it on,you cant put it on that thick with a roller, you will have to wait for it to kick and it will have a tendency to pull off the coat you just put on..its more easy with a gun..

I use a cheapy from PRO-TEK model 2650 with a 2.5 tip and it putt's out more the the old lady,i almost didn't want to spray gel through it!1 it is a really nice gun and well worth the money..
http://oemproamtools.com/protek/hvlp_g.htm

i got it from a place called the color shop from a friend of mine lee,,708-547-0855..it was under 100.00 bucks, i also got the taller cup..