Re: Timney Straight Trigger
Most of it is in the geometry of the trigger. The pull point vs. the center of rotation vs. how much force the trigger needs to disengage the sear. If the trigger is an arm and it sits directly under the pivot point then you get 100% efficiency on the pull. But, depending on how far off center the sear release is is how much extra you need to pull. The closer to center over the sear release, the easier it will be to pull. But, you then have less movement of the sear, requiring longer movement of the trigger. so you need to be just far enough off center so that little movement of the trigger is required to let it off. But still have enough meat between trigger and sear so that it won't go off accidentally. The AR trigger is one most of us can picture. It has about 1/32nd of an inch of hold sear to hammer. And just under a half an inch from the pivot point out to the sear release point. The trigger gives enough leverage @ 1-1/4" to relatively easily pull.
I've seen a lot of curved triggers that are forward of the pivot point and therefore require more pull. When the trigger is straightened down underneath the pivot point you get better efficiency of pull. Most factory trigger area set-ups are such that having a curved trigger directly underneath the pivot point won't leave enough room behind the trigger. So, it is moved forward. MM's almost doesn't have enough room between the end of the trigger and the trigger guard.
It's one of those things. It's always been that way. And until these type triggers came along no one wants to change it.
FWIW, I like them better the way MM has it now.