ORIGINAL: Matt / PA

The most lethal hit has to be quantified as the quickest simply because either something is lethal.......or it's not. Sort of like either your preganant or not, there is no such thing as "Most Pregnant".
A lethal shot is a lethal shot but what makes one different than the other is the speed at which it will do it's job.

ORIGINAL: Matt / PA

It really is, and when you see it happen you know exactly what you hit. The last deer I hit like that literally jumped straight up in the air at the shot, sprayed blood 6 ft out either side, hit the ground and flipped over all in one motion. I was like.............[:-]
Exactly what mine did this year. Gosh I shot it and it jumped straight up in the air ran sideways down the hill 30 yards and flipped over!Oh yea and blood everywhere![:-]

If you want to see a PERFECT example of this hit watch the newest Primos Bowhunting video #4. Will Primos shoots a buck facing to the left in this exact spot. The shot looks a tad forward but trust me it's not. IMO it'sa prefect hit but doesn't give you quite the margin for error that a higher, slightly further back double lung shot will.
Anyway the deer is hit and sprints off maybe 20 yards and just CRASHES into a small tree and flips over dead in some water. I'm talking 2 seconds TOPS and that deer is on the ground.

ORIGINAL: bigbulls

Yep.

If you can keep the heart intact but take out either a main vessel or lungs the heartcontinues to pumpblood but out ofthe holes rather than to the brain.

If you take out the heart then the blood simply drains out of the body instead of being pumped out of the body.

Think about a water pump with the same hose attached to the inlet and outlet thus making a closed loop like our circulatory system. If you punch a hole in thehose the water will go spraying out every where until there is no more water to spray. If you bust a hole in the pump the water will simply drain out.

Which one would take longer to deprive the brain of oxygen?

Here is an example of what I believe is a blood vessel shot off the top of the heart of a main vessel in the lungs.
http://vids.myspace.com/index.cfm?fuseaction=vids.individual&videoid=2 690954

The quickest kill in my experience is the one that takes out the vessels at the top of the heart, not the heart itself.
Generally this is combined with a double lung hit but what puts the animal down so quickly is the complete removal of blood pressure and blood supply to the head/brain. The heart keeps beating butno oxygen rich bloodcan go to the head and the animal will black out incrediby fast.

A straight heart shot deer will generally run even further than a double lung because the blood pressure, blood loss happens at a comparatively slower rate than if you severe the high pressure vessels above the heart.
I actually even think ANY of the high pressure blood vessels might put a deer down quicker than a straight heart shot.....carotid, femoral etc.

That said a perfect solid double lung shot should rarely if EVER allow an animal to make it even 100 yards, and I think the distances vary between 30-40yds and close to a 100yds on average based soley on whether the animal had a full breath of air just prior to the arrow strike. This would keep the CO2 level down in the blood for a few seconds longer keeping the animal on it's feet a few seconds longer.........if the animal just let out a breath and you center punch the lungs I think the distance traveled will be much shorter.

Quickness of kill (animalexpiredfrom my experience)
1. Top/front of the heart/high pressure vessels combined with the front of thelungs obviously
2. Double lung / other high pressure arterial hit
3. Heart shot
4. Liver, lung
5. Liver
6. Liver Gut
7. Gut

One lung deer conceivably could survive the trauma so I din't rank it and since we're bowhunting, head shots are out and spine shots while requiring no tracking generally aren't an intended target.