The Blazer brass was made as an "upgrade" (slightly more expensive) -- reloadable brass version of the Blazer line. Orginally, the aluminum casings were what made the Blazer line what it was -- fairly high quality cheap disposable once use ammo. Guess they wanted to expand their horizons. I've used the aluminums in my 9mm, .45, and .38 with no ill effects (aluminum is alot softer than steel so I really have no worries about it in the autos; this might keep me from using it as an autoloader defensive round). The .44 special is great -- big GDHP and good reliability which I do use for ccw. The only bad thing about the alum .38 rounds (158 LRN) is I did have one back out under inertia when shooting my .38 snub (new model 40--not airweight) effectively stopping the gun -- suspect it was improper crimp. Was easy to clear, though, and I wouldn't have used the LRN for CCW anyhow.
In any compromise between good and evil, it is only evil that can profit -- John Galt
Blazer is just about all I use because of the low cost. Not only that it is good ammo. Have not had any ammo failures with the aluminum or the brass. (Thousands of rounds) It fires much cleaner than other brands I have used. This makes for easier cleaning. For some reason Blazer ammo has gotten a bad reputation. The indoor range/gun shop I go to won't let you use Blazer in their rental guns. I know they don't like the aluminum getting mixed in with the brass in the scrap barrels. When I asked why they didn't like it, all they said was "It's Junk". I think they are just mad because I don't buy my ammo from them. Just like any ammo you use, try it first to see how it works in your guns.
Taurus Fan our Wally World here in TN carry CCI Blazzer rounds and I have only seen them in brass and I bought some 45acp and 9mm (you will be happy a Taurus PT111 for the wife) not bad would only use them for target practice.