[Tolnaftate2004]

1. You can't modify clientr variables on the client-side. You can perform tests with client variables, but for security reasons, you will want to use clientr variables, which means you will have to modify them on the server-side. If you don't know what I mean, I'm sure someone will post a link here for you. Otherwise, look into triggeraction, triggerclient, and triggerserver if you're not already familiar.
2. Because clientr.ammo is unchanged, it is 0. Then, when you check if clientr.ammo < 0 (which, I am assuming should in fact be '>'), that test fails.
   
3. You are mixing GS1 and GS2, which is bad form.
   
   To set the player's chat, use player.chat = "foo".
   To set the player's attributes (like #P2), use player.attr[2] = "bar".
   To replace a GANI, use replaceani("baz","qux").
4. Use = as assignment only and use == as comparison only (see the 3rd line in your code). The engine will fix this for you, but it is bad practice.
5. You will only need one //#CLIENTSIDE.