What is the differnce between a Beman mfx 400 29 3/4" with a 5gr.(150 gr) per inch insert and 125 grain head. Or the same arrow with the same added wieght upfront? 100 grain insert and 175 gr head. (instead of wieght tube)
The weight tube doesn't affect the spine of the arrow and will probably lower the FOC. 275grs up front will weaken the spine of the arrow and increase the FOC. Alot of data is indicating gains in penetration with high to extreme FOC.
with weight up front you also eliminate problems with the tube popping the nock out.
The weight tube WILL weaken the dynamic spine of the arrow, but just a tad. Maybe 3-5 lbs max. It won't have NEARLY the effect of added weight up front though.