I use a LEE 20 lb bottom pour. I've had considerable experience with it and have learned a couple of things along the way.
It is critical that the pot be filled with CLEAN lead when you're running bullets. Lead such as your recovered plumbing pipe should be smelted first to get it clean and free from impurities. For smelting, I use a cast iron pot on a Coleman stove then pour the CLEAN lead into an ingot mold and use the ingots to load the LEE pot for casting bullets to prevent junk from contaminating my LEE pot. I still flux the "clean" lead in my LEE pot thoroughly with beeswax before starting to cast. That involves considerable stirring and scraping the sides and bottom of the pot to bring out any remaining impurities that can be skimmed off the top of the molten lead. If you're using a LEE bottom pour pot it should be physically secured to prevent it being knocked over. When running bullets, I keep a thermometer in the metal the entire time. I've found my LEE 20 lb pot holds temperature just fine, once I get it where I want it. For lead roundballs I get the best results running at 800 degrees. I keep a field expedient cover over the top of my LEE pot at all times when casting, and while it is in storage. The cover I'm using is fabricated by folding several layers of heavy duty Aluminium foil into a square shape that I lay onto the rim of the pot.
Of course all other normal protocols apply when handling molten lead. NO moisture any where near your hot pot,well ventilated area, gloves, eye protection, fully clothed...( no shorts or flip-flops on your feet).
With decent equipment and following good safety practices you can enjoy casting your own bullets and balls as part of the enjoyment of the hobby. If you hunt, taking game with your own "home-made" bullets and roundballs adds a whole new level of satisfaction to any successful hunt.