devastation rotterdam on breakthrough
u can also just farm 60 kills while attack over more rounds.
there is a hidden achievment 
There isn’t a picture in your post bud. However since the tasks in this mastery need to be either completed in a single life or a single round the counters will reset between matches. Moreover the ‘hidden’ assignments were patched shortly after release as they apparently shouldn’t have existed in the first place.
I’ve gotta call bull on this… I’ve gotten close to the 20 in one round several times. I have more than 2k kills with the STG44 and have yet to unlock the gold stock. Unless this can be confirmed by DICE this is simply not true.
Patched out shortly after release dude, as I mentioned above.
Yeah for some reason I can’t upload picture. Also my post vanished 
Images are iffy around here dude. It might work if you put a link up from Imgur or something. The forum also likes eating posts sometimes when editing. If you tag a mod they can get them back - @ragnarok013 or @LOLGotYerTags could you help them out?
Here it is. As you can see it does record some progress. Or at least it did. My guess is that you need (or had to) do 50, 60, 70% of assignment. Well, as I wrote that was the case for STG before patch. For Bren and Suomi still works.
Hamada breakthrough is the best map for objective killing focused assignments. With a worth a starting ticket count of 500, and more tickets coming in when a sector gets taken, the games generally last long enough that you can get almost any of them done.
Not saying that you’ll get it on the first try though
all my objective assignments (attacking) were done mostly on breakthrough Fjell as people are literally oblivious to what is happening.
it has massive cap zone on A and if you get crappy team(s) you can often do it in 1 life since
- your team will be full of campers
- enemy team will be full of campers humping those hut’s roofs
this will give you plenty of time to complete the assignment.
For the first A, Just flank from the bottom rear et voila, usually there is one just behind a rock as you go up (occasionally 2) this one will be out side of cap zone.
if for some reason you manage to cap the area look up/youtube the out of bound flanks for both B’s as this will literally place you in the middle with players turned away from you lol.
Ive highlighted for you where people normally camp. the yellow area is a “danger zone” as you can be easily taken down. with an STG you should be able to take down anyone towards the end of the path from where the first set of huts end (between the canyon thing)
ElliotLH Ov3rkiII
It wasn’t in the queue so either the forum monster ate it or LGYT has already found it!
Thanks for checking @ragnarok013.
Conquest or Grand Operations. Get the 10 kills with one life. Hang around the middle flag. Should have around 6-8 kills here. Once captured. Quickly get to their last flag. Run around and lay low. Should complete the challenge.
Hope it helps. Good luck.
Can someone confirm that? Or test it?
IMHO all assignments should have a grind option e.g. in BF1 you needed 300 kills to get the Martini-Henry with a scope.