Glasers are not safe in any sense of the word.I've shot hundreds & hundreds of them.
When Glasers penetrate wood, drywall, 2 x 4's...the kind of fold in upon themselves and stay together, thus not apartment safe. They have plenty of penetration for their weight. When they hit something soft (tissue) they frag real good. If they hit something hard like rock, marble, steel, then they shatter so there's your ricochet proof
feature.
The blacktip Glasers use a heavier than lead tungsten shot (and a smaller tip IIRC) with a larger shot / smaller payload to increase penetration while keeping them able to retain velocity. I've not shot any of these ones but read about them. Supposedly they will penetrate soft armor.
I shot my Chrony with a (homemade) Glaser. It went through the front and hit the dividing metal plate and pretty much folded it over 90 deg. It landed about 10 or 15 ft downrange. The tip, mangled jacket and loose bb's were in the Chrony.
Early Glasers were TC flat points with non compressed shot. Typically #12 shot is in them. Todays Glasers are RN and the shot is compressed. They started compressing the shot in them for two reasons. To get a bigger payload in them and stabilization. Seems the non compressed ones would destabilize and weren't very accurate from the loose shifting shot.
I've made (safety slugs) in many weights from 140, 160, 185, 190, 200, and 225's. Their very easy to make, just two pulls on the swaging press. The little blue balls are freakin expensive at 4.5 cents apiece though so I've taken to capping them with a single OO buck which are much cheaper.
I bought the tooling to make them for the wonder bullet syndrome and I'm cheap.
As it turns out, I care less for the wonder bullet angle and continue to make them because they are scary accurate as a handload and easy to make. Who cares if it frags but I can hit with these babys like no other. So they're like a JSP. If it don't frag, its like ball 45 and if it does frag, woe to them hehe. I don't carry them for SD though prefering to stick with a conventional HP. I like shooting steel with them at the range because they make me look (sound?) good and do break up on steel giving a mediocre assurance of no fly backs. Eh.
I've made a few guys gawk at the range at my full trays of 'Glasers'
When capped with the blue tips, they are indistinguishable from the factory ones.