handgunner will tell you. The aluminum jacketed 85 gr 380 bullet was "looked at' by Winchester for loading in the 9mm. However, it has feeding problems in some guns, notably the Browning High Power, it "fouls" the gas ports in HK squeeze cockers, and it lacked "adequate penetration' in the room temp, 20% jello used for testing (at the time).
Aluminum comprises 1/12 of Earth's crust. It's properties span a wide range, depending on how you alloy it. The aluminum in soft drink cans is too impure and it's soft. The aluminum in a CAR-15's receiver is hard and heat treated.
As for aluminum bullet jackets, the prefered aluminum is soft to facilitate easy expansion.
However, do not assume that all aluminum is that soft. As we saw in the CAR example, aluminum can be quite strong. If you alloy aluminum with Scandium, you can achieve phenomenal strength.
Remember, aluminum can be as inexpensive as a drink can or as valuable as a ruby (Al_2 O_3).
Aluminium is still vastly inferior to steel, one notable advantage of steel, one which Aluminium will NEVER be able to match, is endurance. Steel will last MUCH longer than aluminium because aluminium suffers from metal fatigue rather rapidly. I don't trust it, and never will.
Actually the term secondhander doesn't bother me. All top grade guys had to start at the bottom sometime. Difference between you and me is that I can keep trying and succeed while you are not only a has-been but you are a never-was.