No one has asked on this forum about lead and lube smoke, and today I was pondering why not, so I decided to write a bit about it, as many who I talk to personally talk about it with some concern.
Lead vapor should be a concern of anyone who shoots lead indoors or even outside if they shoot very much. It is caused ONLY if the gun is leading or real close to it. The lead vapor is molten lead which is created by bore friction, due to lube failure, when the lead which doesn't stick to the bore gets sprayed out into the atmosphere by the powder blast.
The most deadly situation comes when shooting large numbers of handgun rounds indoors where the vapors concentrate in the air, along with lube smoke, which I'll address next. If you have ANY leading anywhere in the bore, stop it, and you'll be making no more lead vapors. Gas checks can cause one to believe there is no lead vapor, but if the lube isn't doing it's job, even fairly light pistol loads will lead a bit, but the gc's shave it from the bore and spit it out, thus potentially hiding a lead vapor problem. Most indoor pistol shooters will be using mild plainbase bullet loads, and most who I talk to use some cheap lube which leaves a bit of lead in the bore. (Again, the majority use a cheap, soft alloy along with cheap lube.) Switch to LBT lube and you'll get no lead vapor. -- There are several powders which have come out in the last 10 years which I have never used, but Hodgen Universal is the cleanest burning powder I've ever used, creating almost no visable smoke, (or fire) with light to fairly heavy pistol plainbase loads, when using LBT bullet lube.)
When shooting heavy rifle loads with gas checked bullets, lead vapor will be lower with LBT lube than any other lube that I know of, but there will be some if you are pushing the accuracy threshold with maximum possible velocities. In which case, if the wind isn't in your face, it will all be shot forward 20 feet and more with the powder blast. For this reason, and to avoid breathing lube and powder smoke, I refuse to shoot into the wind at targets, because I think powder smoke is as irritating, and probably as toxic because of volume, as lube and lead smoke. (I'm guaging my notions on how I feel after extensive shooting when the smells come back in my face, with heavy rifle and revolver loads. I shot 16 hours a day, 6 days a week for several months when developing the LBT lubricants and bullet designs. When I couldn't sleep nights because of stopped up nose and coughing up phlem, I knew I was breathing bad stuff!)
Lube smoke, volume wise, varies dramatically with the type used. Alox, which is the most common lube used, I believe, is one of the most serious offenders of all the lubes I've used. First, the fumes are quite toxic. But the huge volume of smoke is caused when the lube flings out off the bullet as it exits the muzzle, leaving a lube star when it's working right, and lead star when it's lubricating limit has been exceeded by pressure and velocity. As the lube sprays out, the powder blast which passes the bullet vaporizes the lube into smoke. LBT lubes will stay on the bullets during flight, at speeds to at least 2800 fps. I believe there may be several other lubes which will stay on the bullet during flight, thus preventing this lube vapor problem, (There won't be a lube star on the muzzle if the lube you are using stays on the bullet.) but few will prevent leading at significantly higher velocities than Alox, so lead vapor can be as serious a concern as with alox. Again, LBT lube will allow the highest velocity potential of any lube I know of with complete freedom from lead vapor, and coupled with minimal lube smoke, depending on the powder type used.
Various powder types burn at various temperatures, with the hotter burning ones being stick powders, and flake in pistol powders, and coolest being ball powders. I burn any powder I can lay hands on, cheap, or have on hand, but when buying powder, especially for rifles, I always try to get ball powder. The flame temperature difference makes a world of difference in throat erosion, which by the way, in my experiance, is just as serious with cast as with Jacketed when velocites are similar. Based on what I've read, and heard from people more knowledgable on the subject than I, ball powders can give double the throat life with heavy rifle loads, and do far better with heavy revolver loads. I've found that when using stick powders, with heavy rifle loads especially, more smoke is produced than when using ball, and I believe this is because of the high temperature gases sweeping the bore of lube residue. I rarely give out theory, but this time I'm doing it based on flame tempereature facts, and the fact that more smoke is produced by the hot flame powders, which, also yield lower velocities before leading and inaccuracy stop development of heavier loads.