VP,
Broad Heads:
Keeping the Broadhead in the Bird, is the Key to recovery. A standered broadhead can be used a number of different ways. A game string (tracker) can be used to help find the bird but the chances of the string breaking after inpact is very high as the bird takes off. Another way is to use of a light washer on the threaded end of a Thunderhead so it will slow penitration down as the arrow enters the bird.

Mechanicals:
There are a number of different brands out there for the Turkey hunter.
Spitfire, makes the 125gr. Gobbler Getters with a 1 1/2" cut, the tip is more rounded (dull) to slow down penitration. Grim Reaper, is also another head that works well with a added light washer but it has a 1 3/8"cut. You can also take your favorite broad head and file the tip down to a dull point, this will help slow the penitration. A wide cutting edge is a good idea for a choice. Rocket Sledgehammer's/ 3 1/2" cut - 150 gr. is a great head with a wide cutting edge. The wider the edge the quicker the kill can be...BT