adding front end weight to carbon arrow shafts

here's a relatively easy way to add more weight to carbon arrow shafts, and increase foc, and add some footing stiffness/durability, all at the same time. the concept is simple - use a tube that will fit tight inside the arrow shaft tube, add weight to that short tubing, ram the short tubing down inside the arrow shaft from the nock side 'til it hits the insert ferrule. the fit of the nail in the weight tube, and the weight tube in the shaft - both MUST be a TIGHT fit! i used carbon express plastic weight tubes that are cut in about 4" to 5" lengths ... 3-1/2" 16D common nail ... 'cept the nail head needs removing, i used a dremel cut off wheel - an alternative is to chuck the nail in an electric drill, run it over a file to take the head diameter down to less than the outside diameter of the weight tubing ... now clean the nail with some naptha or lacquer thinner to prep for the taping ... wrap the cut-off end of the nail with masking tape ... check the fit of the nail into the tube - it must be TIGHT! - add or subract tape if need be ... wrap the cut-off end of the nail with masking tape ... force the nail into the tube ... wrap tape at the ends of the tube for a TIGHT fit ... insert the weight tube into the shaft ... if the fit is too tight, snip off some of the masking tape ... using a length of weight tubing, push the weight tube into the shaft ... ram the weight tube down 'til it hits the point ferrule ... here's a 29.25" beman ics 500 carbon shaft, with 100 grain brass point ferrule, 4" banana 4-fletch and a bohning nock, with NO weight tube added ... the shaft, feathers, nock, ferrule WITH weight tube - a significant weight addition ... add in a woodsman broadhead with alum adapter ... and we've got a footed heavy arrow with high 30.16% foc ... the resulting 29.25" weight tube footed arrows fly like darts out of a 55# holding weight longbow, with no wobble or other erratic flight, and although the arrow spine is slightly lessened, there is no 'tail left' when shooting into target butts. the fit of the nail in the weight tube, and the weight tube in the shaft - both MUST be a TIGHT fit! you can remove the weight tube by unscrewing the point, twisting out the nock, then use a length of 1/16" music wire to force out the weight tube from the ferrule end of the shaft.