Few people realize that broadhead penetration has very little to do with
broadheads. Rather, penetration has almost everything to do with arrow
flight. A well tuned 50 pound bow with arrows that fly without wobble
penetrates better than an 80 pound bow with aberrant arrow flight.
I totally agree with the above..However, a major and I do mean major reason people give as to why the went with mechanicals is that " My field points flew great, but I just couldn' t get the fixed blade heads to group well" . How many times have you heard that one? If you can' t get the fixed blade heads to fly straight it is because your bow is out of tune. Period. IMO most people switch to mechanicals simply because they can' t get their fixed blade heads to fly straight. So instead of tuning the bow or having it tuned, the quick and easy way is to switch to mechanicals thinking their problem is over. The problem is not over. It has only just begun. You are still shooting an untuned bow. Yeah your arrows are grouping better, but the thing is still out of tune and when you shoot a deer that is when the big problem occurs. The mechanicals are not going to penetrate well because they are not flying true.
Probably
the greatest disadvantage of mechanicals in general is that as a group they
tend to be much more critical of arrow spine than replaceable or fixed
bladed broadheads.
Here is another big boo boo in my opinion. How many guys are shooting underspined arrows? Based upon what I read here on the BBS pertaining to different peoples setups, a lot of us are shooting underspined arrows. So in addition to the out of tune bow we are adding to the problem with an underspined shaft. No wonder all the posts here pertaining to mech' s.
Momentum is a linear function of
mass. The idea is the greater the mass the more resistance is required to
slow or stop the object. Think of it this way if someone were to pitch a
baseball and a bowling ball to a batter, and both balls had the identical
amount of kinetic energy even though one is traveling very fast and the
other is traveling very slow. The batter would be able to hit the baseball
and move it in the opposite direction very easily while the bowling ball
would most likely break the bat. The bowling ball has tremendously greater
momentum and therefore is much more difficult to stop or slow down.
And the final straw...Momentum. Once again, how many of us are using 300 or 350 grain arrows for hunting? Way too light for me and IMO way too light for you too. Yeah, it' s coming out of the bow at 275fps but if it doesn' t penetrate properly what is the point? So lets see...Untuned bow, underspined shaft, arrow that is too light to carry adequate momentum. Recipe for disaster.
With all that being said, what it comes down to is knowing our equipment. If you don' t know how to tune your bow...Learn. If you don' t know how to select the proper shaft size...Learn. And by all means, don' t get so caught up with arrow speed that you will sacrifice penetration. If the arrow chart lists two or three shaft sizes for you setup, don' t automatically go with the lightest because it shoots the fastest. A heavy shaft is not a bad shaft. Do not take shortcuts.