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I admire your optimism, but this is nothing like previous titles.

Do you honestly believe it is a beta?
Get your early access key by watching twitch... It's not a beta, it's a marketing event and very little is likely to change between now and launch.

The gunplay could be a bit better, but the ttk difference you're describing between a pistol and m4 just sounds like not all of your shots are hitting with the m4. And yes I do believe they could change certain things about the gameplay. After the disaster of 2042, they've learned what happens when they don't listen. I mean the fact that they abandoned the "operators" approach they took in 2042 and went back to the class system we asked for is proof of that. 

Again, give it a try on semi-auto. You might not be seeing when the hit markers aren't showing. It might be net code issues. Try on semi auto and see if the number of shots is similar to the M18 that way. If it is, the problem is the bloom. 

So the game just gives you hit markers even when you aren't hitting things? That's good to know. Don't know who programmed that in.

The issue you're noticing is the M4 has severe ADS bloom. Go into the range, mag dump into the wall, and pay attention to where the tracers are going. You'll notice that the cone of fire starts to massively open up. The M4 does more damage than the M18, the problem is that most of your shots aren't landing. Traditionally you would just tap fire to control the bloom,  though that's not my favorite mechanic. You can actually switch to semi auto for the M4 too, which eliminates all bloom, and you might notice you perform better than way if you find the pistol works better for you. 

If people aren't tanks that can take 20 bullets then why does half a mag have problems downing someone with an M4 while a 9mm pistol will kill them in 4 shots?

If they're going to make a class locked conquest mode then make a class locked mode for the other game modes too. Although class locking everything is how you get good teamplay. An assault with a sniper rifle is more likely to sit back and not actually be an assault.

It's like COD because it's the general vibe they seem to be going for. The combat feels like it's straight out of CODs knockoff conquest mode and the guns feel horrible and not at all realistic. As far as they're concerned, faster fire rate equals more deadly just like COD. That's why the meta weapons are SMGs.

The fact that it's in beta means nothing. Betas are for fixing bugs. If you truly believe that they'll change core gameplay at beta stage then you're delusional.

First of all, keep in mind it's still in beta. Nothing is finalized, and the whole point of the beta is to get feedback and fix bugs. I think TTK is fine honestly. Real people aren't tanks that can take 20 bullets before dying. I don't think weapons need to be class locked across the board, they're giving people an option. If that's what you want, then play that mode. And it's absolutely crazy to say this is "the next COD game." Why, because it has guns, sliding and jumping? What do you want them to do about that? Real people can slide and jump. It's not the first battlefield to have sliding. It still has the heart of battlefield. It promotes team play, with squad revives, squad spawns, 32v32 large map gameplay, vehicles, objectives, being able to revive in general, etc. The list goes on and on. To say this is just like COD is pure ignorance. Have an open mind. 

They didn't listen to players at all. TTK is all over the place with handguns outperforming rifles. I can mag dump a guy with an M4 and not get a kill but when I shoot someone 4 times with the handgun they die quickly. Engineer can run anti-air and anti-tank at the same time instead of engineers having to work together to combat all vehicular threats on the battlefield. Weapons still aren't class locked except in one single game mode. Assault can carry 3 guns? Like WTF. No server browser. Grenade throws are CODlike laser beams. There's a lot of issues indicating that they have done literally anything except listen to the players. The only good things about this game are the vehicles feel more balanced and less invincible, and the revive mechanic. Other than that it's the next COD game.