This achievement needs patient and consistency.
Reach the weekly objective is relatively easy, 7000 bolts, just by doing 2 quest stations can be done, and you can do this in just one day depending your stamina. It also can be reached doing only challenges or combinations of every mode.
The important thing is to keep coming back every week, which resets on Monday.
You should plan ahead if you have upcoming vacations of seasons where you won't be able to play during the week, otherwise your previous work is ruined if you don't meet the objective for that week. I didn't reach 7000 bolts on week 3 and had to start over.