Or packing tape hey! I know I know, maybe I went a little over board. I tend to do this
1) Go to your local dollar store and buy a Tupperware container big enough for the gun. Usually the same size as the one your mom kept cookies in
2) Wrap the firearm in a tea towel or shove it in a sock
3) Lay down a good base layer of bubble wrap or newspaper on the bottom
4) Place the towel wrapped gun in
5) Completely fill the box with newspaper, bubble wrap, wood chips, foam, or what have you
6) Put the lid on the box and completely tape the box in
BOTH direction with packing tape
7) Wrap the completely taped box in plain brown parcel paper and write the address
8) Completely wrap the entire parcel in packing tape again
9) send it as quick as you can, with signature required, insured, tracking number, and contact the seller within 15 minutes of leaving the post office
10) Track it yourself, to ensure it arrives safe. I feel responsible until the buyer receives it
11) Once delivered, contact the buyer and ensure they are satisfied with everything.
That's my routine. Only complaint I get is, "Why the F### did you put so much tape on it"? Well... Can't hurt. If it was a nice firearm and the postman left it in the rain for 8 hours while you were working, would you prefer it to be water proof, or a completely soaking wet shoe box that's falling apart with a gun that needs complete disassembly to dry out and re oiled to prevent rusting?
If you ever buy from me, I assure you, this is how you will receive it lol