We're excited to announce that we've fully migrated the Xbox Forums to their new home, here on the Microsoft Community forums!
As of today, going to forums.xbox.com will redirect you here to the Xbox area of the Community forums. We've moved all of your existing threads over so you can continue and start conversations with the new forums experience.
We sincerely appreciate the feedback you have provided over this transition and can't wait for you to check out the new Xbox Forums!
No you can't, but you can play with all the guns in offline mode. Just choose to play a split screen game, but don't connect the second controler. You can then add AI bots to fight against in the game options menu.
Its a good way to test out guns without needing to unlock them in combat training. To be honest though, it's not hard go through the ranks in normal combat training.