Wow I have a 600 grain gold tip arrow, I added 27" of aq tubing to my 29" arrow and my 125gr head with my 50 grain brass weight and it is a thumper and didn't change spine at all:-)

Dalebow, you might want to do some more spine testing. Whenever I added stuff like aquarium tubing or weedwacker line or anything the full length of the shaft that didn't add and spine of its own, it reduced the DYNAMIC spine of the shaft. It won't change the static spine, which is what is measured on a spine tester.

THANKS FOR THE INFO BUT THEY HIT EXACTLY WHERE I LOOK AND SHOOT STRAIT:-)

DaleBow, you could shoot a 28" Carbonwood VMaxx 4000 with 100 grain brass insert and 100 grain BH adapter and the 145 head for 345 up front and have a 695 grain arrow. I think this would fly awesome out of your bow!! Shawn

I have some pretty heavy arrows working. Old style skinny 40/60 beman inside 33" beman 300 ICS. Then filled them with salt. 1280gr. total including Grizzly 190gr heads. BBP

I just got in a few Grizly Stik's for testing. I would certainly like to see how these Mamba's compare.

I shot 57@27.