Warhammer 40,000: Inquisitor - Martyr

By the time I was done with all Tech-Adept achievements I was still left with about 80% progress left towards this achievement, but found a pretty quick and easy way to grind it out in 10 or so minutes.

First, equip your Inoculator with as much Hydrazil as possible, because it lowers the summon cost AND speeds up the construct cooldown.
You want to have as many summoning slots as possible, so put on a Technomartyr Vestment, Technomartyr Girdle and any weapon that has 3 summoning slots available, which should put you at 5 total.
Next step is to put a Psiloi Vivisector into each of the available slots, as it is the cheapest of the constructs to summon, and each summon actually spawns in 3 of the constructs, which significantly boosts progress towards this achievement.

Now that prep work is done, just spawn into any mission you want, camp in the starting area, activate your Inoculator and push all the summon buttons as quickly as you can. When you run out of Data-Flux, just wait a little while to recharge, but as long as you're using the Inoculator, the Hydrazil will make it really difficult to actually run out.

Note that after summoning 300 Vivisectors, you unlock a perk called Mechasapient that allows you to spawn in 4 of them per summon instead of the 3, further speeding up this process should you choose to equip it.