A lot of it has to do with what the non-sniper player is doing. If you can draw that player out of position you'll likely be able to bully the snipers.
Double sniper teams usually entail two players pushing one side. Use that to your advantage and maneuver/flank with your ally. All failing one or both should be able to take the rest of the map.
If the other player is going t2 soviet w/ conscripts or a UKF vickers into WASP bren your best bet really is a blob of G43 grens. Your strat is pretty much surviving long enough to tech to the midgame. Just remember you'll likely fighting a 2v1 in many cases, so don't expect am advantage.
That said, if you're up against soviet snipers with USF support I find it much easier to draw soviet snipers into over extending, whereas t2 soviet or UKF support tends to dig in and lock you down/out of fuel or vps.
Aye. I normally can't put all that faith in my ally that early so I always intend to win my side and then fight with my teammate. I prefer to see 2v2 as a 1v1 that then introduces two other people who were 1v1'ing and then becomes a 2v2. I suppose it's flawed, but I've always preferred anything that exemplifies individual ability rather than team wide strength. The person I play with the most and I refer to it as double d***king when both players are attacking one instead of fighting their respective side.