Buffy's "The Turkinator" Guide!
I completed this achievement the 22. November 2009 at 16:17. Of course since I did this achievement so earlie after the Pilgrim's Bounty started, there were a lot of people farming the Turkey's I needed for this achievement, but I found out the best area to farm these.
First off, I will explain a bit in general what you need to do in order to obtain the achievement. When you start killing the turkey's you get a buff, this buff counts how many turkeys you kill, and you have 30 seconds between each turkey you kill before the buff disapears and you need to start over again. In order to get the achievement you need to get "Turkey Triumph", and to do this you need to kill 40 turkey's without the buff disapearing (at one time you may say).
Red Area: This area is where you will find most turkey's, but also most people farming for them, giving you a less chance of getting the buff "Turkey Triumph". Start at this area, and kill as many turkey's as you find. Start at the zepplin house and make your way around Brill and up to the yellow area.
Yellow Area: This area has less turkey's, but also less people farming for them, since this is a bit further away from the questgivers and npc's in Undercity. After you have done the Red Area go here and get your achievement completed.
If you follow my guide, you WILL get the achievement completed, and I promise you this is the fastest way. I have tried a couple of other routes / options of getting it done, and I found this way the best. I wish you good luck!