I don't have the internet available through my console and wanted to get everything in the game but have just been reading that you can't get all 43 guns without getting the Cannon gun, which has to be gotten through Uplay. Is there anyway around this or can I only get 42 of the 43 guns listed in the handbook?
"I dreamt I was a moron" Squall, Final Fantasy VIII
The Cannon just gets you the listing for the .44 Magnum, just like all other signature weapons get you the listing for their normal counterpart. You're missing a completely different weapon. Go through your weapon list in your journal to see what you're missing. Most people usually miss one of the vehicle turrets, the one you can find on the boats is different than the one on the SUVs.