Okay you can feed a glock anything as long as its jacketed, ball ammo for target practice, jhp's for defensive carry with a CCW of course or home defense. Dnt want ball ammo flying though a bg and hitting an innocent bystander or plowing through a wall and possibly killing a love one or maybe a next door neighber.. For protection jhp is always BEST.. DO NOT AND I MEAN DO NOT SHOOT LEAD ROUNDS THRU ANY GLOCK unless you have an aftermarket drop in barrel from ie, lone wolf, kkm, bar-sto ect.... Back to the cartridge any jhp from any major company ie, remington, winchester, federal will suit you just fine as long as its cycles & is reliable in your firearm. I have a glock17 and a glock23 which is my edc and i keep em both full with winchester pdx1 124gr +p and pdx1 180gr for the 23 it works flawlessly. Speet gold dots are great too. Jus practice some with you carry load to make sure it cycles through you gun, Dont want any surprise god forbid you ever need it, plus you wanna get formiliar with you carry round and recoil with it because premium loads tend to be hotter ie more recoil exspecially in a forty which already has kick cuz its all ready a hot round. 165 vs 180gr honestly there is no diffrence if so its minute. I like the biggest weight in any caliber im shooting besides the 9mm hence the 124gr +p. Yea its slower but it hits harder.