Battlefield™ Hardline

From main menu select "Multiplayer"
From the next sceen select "Gun Bench"
From there switch from "Gun Bench" to "Character Customization"
You need to customize all: Swat, Undercover, Thieves and Bangers.

The achievement requires you to get a Gold Service Star with the M1 Carbine. The first Gold Service Star for a weapon is earned at 275 kills with the weapon. The weapon was added as part of the 'Robbery' Title Update and costs $66,000 to buy. Like all WWII weapons in the game, it's very limited in attachments with only 3 attachments available.

This weapon was added in the Betrayal DLC for Hardline and will cost you $25,500 to buy. You may better know this weapon as the Springfield, which is a bolt action rifle. Just like every other WWI and WWII weapon that Visceral adds to Hardline, this weapon has little to no attachments. The weapon is classified under the "Sniper Rifle" section of the gun selection screen, and can be equipped as any of the 4 classes. The only 2 attachments you can add to the weapon is a 6x hunter scope and a silencer. Like with other gold service star, it requires 275 kills with it.

To unlock this achievement you will need 275 kills with the 1887 shotgun.

To buy the gun it will cost the user $50,000 ingame cash, As you continue to earn service stars for the gun you can unlock and purchase 2 mods they are sawed off stock and short barrel.

To reach rank 150, you need to earn total of $11 325 000 ingame currency. Comes with time and many hours or you can use boosting method.

Best boosting method is:

1. Get at least 4 players together
2. Rent a server, so you can kick ppl who interfere
3. Put match time to max, I think it was 1h 30min, plus max points
4. One person is on one team, 3 others on other
5. Meet somewhere, someone from 3 guy team puts down spawn beacon
6. Lone players keeps headshot killing other 3 as they spawn, earning kill, headshot and nemesis bonus. Nemesis bonus appears after 3 kills.

A total of 275 Kills with the M1A1 is required to unlock this achievement.
The Thompson M1A1 is weapon available for all players and does not require any purchases to be unlocked just the patch that has already been released.

Maps that have nail gun:

Backwoods: easiest map to obtain the Nail Gun. When the match starts, simply turn around and run towards the back of the map. If you go far enough, you'll see the weapon spawn near a small trailer or in a large wood cabin in what appears to be a lumber yard.

Black Friday: Spawns the weapon near the escalators on either side of the map. Keep an eye out, as one side is on the second floor and the other is on the ground level beside the escalator. This one is also near the spawn point on Blood Money, though you'll have less luck obtaining it as it's in the direction most players will be heading.

Code Blue: Has one spawn that is easy to identify an done that is kind of weird. The first is near the construction area. There's a series of "stairs" in the back of the building, which you use to get to the top. The two buildings connect by a thin beam, so be careful not to fall if you climb up the wrong building. The other spawn is towards the "city" area on the other side of the map. In a small, fenced off area beside a ladder you'll see the Nail Gun.

The Beat: The Nail Gun spawns in a two floor building relatively close to the spawn. People often scoop them up on the way to the middle, hence why you don't see them very often.

Got your back:
Bounty Hunter game mode, players drop "bounties" which appear in the shape of giant coins on the map. The enemy coins grant you score, they are red. What you'll be aiming for are the blue coins, which are those that your allies drop once they are killed. When you pick these up you deny the bounty, which saves the enemy team from picking it up for a point. Simply follow your allies around and pick up 100 blue coins after they die and the achievement is yours!

Dead or Alive:
Much like Got your back but with little difference: You'll simply have to keep an eye out for dying enemies and quickly rush to their bodies, picking up the red coins as they drop them.

To do this, first of all you need to be on the map Cemetery, which is part of the new Betrayal DLC. Around the middle of the map will be a vehicle that spawns, this is the Hearse, and can only be accessed by finding it and getting into it. Once you're in the Hearse, drive up to someone, and just make sure to get out of the car before it runs them over.

You have to be level 50 ingame before you even attempt to start getting kills that count towards this achievement.
So in the newest Betrayal DLC, a new feature has been added to Hardline called the Gun Bench. The Gun Bench can be accessed by clicking on the "Multiplayer" tab. It should be among the multiplayer options. In the Gun Bench you start out only being able to customize 3 weapons, but the max you can customize after unlocking the other slots is 5.

To get this achievement you must unlock the other 2 Gun Bench slots. The 4th slot is unlocked by completing an assignment that requires you to customize 1 weapon in the Gun Bench (although you can customize up to three at this point) and then get 100 kills with those Gun Bench guns. The 5th slot is unlocked by having the previously mentioned assignment completed, customizing 4 guns in the Gun Bench, customizing 4 outfits (which is also done in the Gun Bench) and getting 1,000 kills with Gun Bench guns. Once you have customized a weapon in the Gun Bench, make sure you press start and save and quit.

In order to equip the Gun Bench gun that you customized, enter a match and go to whatever class the weapon is for and there will be a new option at the top of the gun selection screen that says "Custom 1", "Custom 2" etc. Choose any of your custom weapons and next time you spawn you will have the Gun Bench gun equipped. You can't edit the weapon ingame, only in the Gun Bench.