I have a Drenalin LD, the limbs are turned down as tight as they will go. My draw length is 31in. Right now I shoot beman MFX 400gr. arrows with 100gr. broadheads, the set up is good. However when I looked at the beman arrow chart it recommended 340gr. arrows is there anything to gain from changing to a lighter arrow, and could I damage my bow. Just looking for some input. Thanks

I believe the chart reccomended a .340 spine,not a 340 grain arrow.

If you are shooting a .400 spine as I believe you might be,it is way too light on spine.

I assume that bottomed out limbs that you are shooting 70#'s.

What he said. You got confused by the numbering. 340 is stiffer than the 400. I also agree, you're probably underspined with the 400s. That should show up if you're shooting a fixed head.

31 in. draw or arrow length? If it's draw then your arrow is likely longer. What draw weight? If it's up near 70 lbs. and over 31" you're going to need stiffer than a .340 deflection shaft. Shaft weight can be irrelevant of spine deflection but generally a stiffer shaft weighs more (given that the shaft is of the same model from the same manufacturer).

I agree with what most are telling you. You need to go to the 340 spined shafts and not worry about the weight. My Draw length is 28.5" and I shoot a 27.25" arrow, so your arrow is not necessarily longer than your draw length. It just depends on how you are set up

Dan