It's not too bad to do . I got my Ballista & DSR bloodthirsties on ground war . The SVU i don't look forward to doing though as that WILL be rough (maybe in hardcore?).
You will have to find a nice sniper roost and just pick people off as they come into view. I find that the most effective way.
Exactly... Had to do hardcore kill confirmed for the svu, took me about 35 to 40 level ups from prestige to get the gold on each sniper, was almost able to get two snipers per prestige. Each sniper had between 500 - 600 kills on it to get gold.
The blood thirsty metals were the hardest to obtain but were still doable on certain maps against the right players, noticed it was harder against Christmas noobs for me as they didn't follow the same routes and were chaotic going down low traffic areas i would use to switch up my vantage point, caused me to lose out on a couple by having to kill them with my pistol or get killed by them bit expecting them to be there.
I thought 1 blood thirsty would be impossible with the crossbow. Fortunately..
Just keep trying. I wouldn't personally do it camp, but if you just keep your distance, on a map such as carrier, you will be able to pull it off. Slowly but sure. May take you a few days, but it will happen.