For your information: If you are a full time sworn law enforcement officer, you can qualifiy for a guard card by just filling out the application, and sending it, a copy of LE ID and a check to BSIS. You may start working as soon as the letter is in the mail.
For a gun card the rules are the same, fill out the application, write a check for the correct amount, a copy of your ID, and mail it to BSIS. Again, you may start working armed as soon as the application is mailed.
Any questions, go to BSIS website (under Consumer Affairs) and look at the LE question and answers.