Welcome! Thanks for the story. Go to a local range and do a little BS'ing. You're bound to find someone more than happy to help you get started on the right path. Safety first. Then practice, practice, practice! I agree with getting a .22. Best to start with a single shot to learn proper technique but you don't have to. For the gauge I'd get some cheap bird shot for practicing and home defense. Bird shot is "less" likely to shoot through walls in your home. Get some buck shot for doing business. As for the .223... when you get a chance buy a variety of ammo and see what you rifle likes best. Above all things... be safe.
The number one cause of death in the 20th century. 290,000,000 citizens were first disarmed and then murdered by their own governments. This number does not include those killed in war.
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