On the weapons themselves, I'm not an expert, so I stick with weapons that are manufactured by good reputable companies. I owned a cheapo .22 pistol once, and every time you fired, a small chunk of metal would fly out the side. I think the chambering clipped a tiny piece of the casing. Caught one in the cheek, and sold the gun to a guy for very little, but warned him about the problem and why I was selling it.
I never put hot loads in my firearms. It's all to SAAMI spec or less. My wife's Sig 225 doesn't like most commercial ammo. I found an ideal mix of bullet weight and powder charge to cycle it flawlessly. Some firearms like the Ruger Deerfield Carbine in 44 mag have a very narrow range of acceptable ammo. The bullet weights are limited to 200 to 240 gr. The powder charge on "cowboy" ammo will fire, but doesn't produce enough gas to operate the piston. PMC 240 gr JHP cycles it perfectly.
Getting rid of that cheapo .22 was a good move. It's a shame that another person has to continue dealing with it. Improperly or unsafely operating firearms just give fodder to the anti-gunners to add more regulations or bans.