Sniper: M40A3 or Barrett50. cal (i would advise the M40
Perks: Bandolier, stopping power and Steady aim (must be used)
You can use either scope you want (I use the normal scope)
Techniques
There are many techniques to non-scoping here are a few:
1. Jumping------------ Is a decent technique, as you land you shoot and if timed right you should beable to kill that noob... this also works if you jump of buildings
2. Left to right---------Alright this is the most common one and is kind of usefull, however isnt my favourite technique... what you do is you move left to right and then shoot
3. Raising gun---------- Im not sure if many of you guys no this one, This is how i do it... you shoot and straight after move the gun up, the trick to have a high sensitivity i would recomand 7(very high)
4. Switching Gun---------Okay this technique is very usefull but is kind of risky, what you do is you shoot and press triangle twice so you change to your pistol and right after back to your sniper... the problem is that if you change to your pistol and your cant change back to your sniper it takes quite a while to reload
5. move gun either to left or right---------- This is a bit like number 3 but instead of moving to gun upwards move it to the left or right... again this is really usefull
6. Crouching--------------When you shoot crouch whilst pressing R1 because the accrucey is better
7. Jump and prone--------This is the same as crouching but has probley better accrucey