Might as well start this so that whenever I feel like it, I can make a post here on stuff. Copy Pasta first though:
On the Usage of Tripod Mounting Mgs ingame, namly, the M1919A4, Vickers, and MG34/42 Lafette:
1) YOU DO NOT BELONG IN FIRE FIGHTS. You do not take it into fire fight conditions. You do not take it into enclosed spaces. You do not try to set up in the middle of a fight or a flag area.
2) You DO set up in enfilading positions where you can't be seen directly from the front. This is actually EASIEST with the 30cal as you lie down to use it. You set up behind a table or a rock or other cover, and fire at a diagonal angle into your preset killing ground.
3) HAVE A KILLING GROUND SET UP. Make sure you can clear fields of fire on the enemy, and be sure to keep the gun pointed at the less noticeable spots, that's where a sniper is gonna go to try and shoot you.
4) Join up with a squad if on defense, and have at least one of them guard your ass.
5) When you set up, make sure that its behind the front lines. This is easiest with the lafette due to the telescopic sight, but is perfectly well done with any of the tripod mountings. You set up behind your own lines, and have the killing field set up as where the enemy is going to try to defend/attack front
6) You are an area DENIAL weapon. When defending, you can set up pointing along a single street or avenue of attack, and literally lock it down. This will often end up being boring, you'll wipe out a couple squads, then for the rest of the map only hit stragglers. HOWEVER, this is critical. You have now shut down an entire avenue of attack for the enemy, who will now be funneled into other areas.
7) CHANGE POSITION! Have preset positions (you can even start your own local server to scout this out, I do this a lot) where you can fall back to or change around once you realize that there's a squad or even just a single guy out looking for you. Countless times I have pissed off a squad to the point where they come specifically after me, I change position, then when they come up on my old position to find I'm not there, I mow them down.