I believe another user did this once. Can't remember who, but I figured I'd give my personal preference. I'm gonna do one from each game from CoD 4 up to BO3, as I haven't played the first three or IW. Again, my own opinion. With that said, here we go.
AK47[]
Now, I was introduced to Call of Duty when CoD 4 was old news. Like My first CoD was Black Ops. So, mind you, I never played the multiplayer. With that said, it was hard for me to pick between the AK47 and the M4 Carbine. But when it came down to it, the AK47 is better in my opinion.
STG-44[]
Come on, was there a doubt? I didn't need to play the multiplayer to know that this was the best rifle in the game. It could be the nostalgia talking, but I'm pretty sure it's the fact that it's the only full auto assault rifle in the game. I'm more of a full auto guy if you can't tell.
M4A1[]
This is where I'm gonna have to go with the M4A1 here. I felt that it had greatly improved from the CoD 4 counterpart. I loved everything about this gun.
Galil[]
This was also a tough one. I didn't know if I liked the Commando or the Galil more. But after thinking about it, I have to give the edge to the Galil for default mag size. I liked the five extra rounds, but when you put on extended mag, holy shit. An extra 15 rounds! That's half a normal mag! I always called it a light light machine gun, after that.
ACR 6.8[]
I bet you were wondering about this beaut when I said the M4A1 instead of this one. No, I liked the MW3 version just a tad more. But don't worry. I didn't forget about it.
M27[]
This gun was my go to. I know a lot of people worship the AN-94, but I don't see why. Maybe because it's the futuristic AK47, but whatever. Was very disappointed that this was in only one zombie map. A crappy map, to say the least.
Honey Badger[]
Ok, can I just say how much I fucking loved the Honey Badger? This gun was one of the reasons I actually enjoyed Ghosts. Was a little upset they didn't bring it back in Infinite Warfare. Yes, I know it goes by a different name in Modern Warfare Remastered, but that involves me actually giving a shit about supply drops. Plus I don't own MWR, so...
Bal-27[]
I might get hate for this, but whatever. I know I'm not the only one out there who likes this gun. Everyone I talk to says the AE4 is the best assault rifle in the game. I like the idea behind it, but I can't aim worth a damn with it. The Bal-27 on the other hand is a gun I can rely on.
KN-44[]
Ok, I know what I said about futuristic AK47's, but I don't care. This is the only gun that got to level 2 prestige. If I had unlocked the Peacekeeper MK2, then maybe that one. But I didn't.
So that's that. What's your favorite assault rifle in each CoD? I'm probably gonna have an SMG list out in a few minutes after posting this. Thanks for reading!