m12s bug

I have a bug with m12s.
When i play a map, first take my first bag, and then my bag with the m12s, i first get the pistol in my hand. then, when i switch to M12s, it just have 5/80 in ammo instead for 40/80

Fix it?

i have bad english, so i make a video ^^

http://www.xfire.com/video/28f243/