So recently I have been tuning some new shafts.  I like to use a 50 grain insert and then adjust point weight as needed.  I'm a little perplexed as to why gold tip came out with these looooonnnng aluminum inserts (center) over the old small 50gr brass insert (right).  These inserts really stiffen up the front few inches of the shaft which has resulted in longer than expected or "normal" arrows for me.  The standard insert (left) and the old 50 grain brass inserts are great cuz of the size but man these new inserts are long!  Am I correct in assuming the long insert will result in a longer shaft due to it stiffening the front few inches more than a normal sized insert would?

Based on my understanding of tuning dynamics, the longer 50 grain aluminum insert will require a slightly stiffer arrow. This results in the need for either more weights up front...or a longer arrow.

This is due to moving the center of the mass weight further to the rear than the 50 grain brass weight which had the weight centered closer to the front. 50 grains is not 50 grains in terms of dynamic spine....rather its the weight in relation to its location position in the arrow. To make the point clearer if you moved the 50 grain weight all the way to the rear nock position, it would increase the dynamic spine the arrow...not lessen it.

I have the exact same issue with the Gold tip 100 weights. The 100 grain brass glue in adapter doesn't tune the GT the same as the longer 100 grain brass screw insert.

First I've heard of this, and I'm perplexed as to why anyone would want to use one too.  Fortunately, I have approximately a lifetime supply of the standard inserts and weights.  The thing that strikes me is how hard they would be to remove without damaging the shaft.  With the standard inserts with or without weights, I have to screw in a field point, the heavier the better, and heat it up little by little, without scorching the shaft, so the heat travels down the insert and melts the glue.  That would be very difficult to do with the looong insert shown in your photo.

I would think that if the longer insert would affect the arrow for you o notice then your arrow is not spined correctly.

Quote from: The Whittler on June 29, 2020, 09:52:06 AM
I would think that if the longer insert would affect the arrow for you o notice then your arrow is not spined correctly.

I think that is 9 Shocks question: if an arrow is spined correctly using a regular insert, would it be too stiff using the long insert?  I think it is a valid question, which can only be answered by testing.  However, in the likely event that the arrow is too stiff with the long insert, something will have to be done to offset that, which could range from using a longer shaft, increasing point weight even more, using a weaker spined shaft, or just staying with the old system of regular inserts with supplemental weights.

It does seem like you are shortening the shaft,which would make it stiffer. I was talking to someone can't remember who about brass inserts. I wanted to know since it wasn't hanging off the front,and was inside the shaft if it would weaken the shaft like more tip weight would. I scooped up a bunch of them off the classifieds,and love the brass insert. They make it to where I don't have to use a ton of weight up front to make them work.

Quote from: McDave on June 29, 2020, 11:02:00 AM

Quote from: The Whittler on June 29, 2020, 09:52:06 AM
I would think that if the longer insert would affect the arrow for you o notice then your arrow is not spined correctly.

I think that is 9 Shocks question: if an arrow is spined correctly using a regular insert, would it be too stiff using the long insert?  I think it is a valid question, which can only be answered by testing.  However, in the likely event that the arrow is too stiff with the long insert, something will have to be done to offset that, which could range from using a longer shaft, increasing point weight even more, using a weaker spined shaft, or just staying with the old system of regular inserts with supplemental weights.

Correct.  It seems the shafts need to be at least 1/2-3/4" longer than the original shafts are.

The GT weighted inserts are nearly if not the same in length from 100g brass to the 50g aluminum. Yes, it can make a slight difference, but unlikely most would even notice.

The short brass insert was not made by or necessarily for GT's. Originally made by muzzy to fit in the .244 shafts, they worked in the GT .246 shafts as well.

BigJim

I'm kind of wondering if the longer insert might help to avoid breaking or damaging the shaft behind the point when a rock or other solid object is hit??
I've seen a few Gold Tip shafts break behind the point/short insert. I've seen lots of wood shafts break there. That location is vulnerable and maybe a longer insert spreads out the stress and it doesn't break as easy??

One thing I have noticed with longer inserts is that they seem to stiffen up arrows a little.  Probably has something to do with shortening the amount of arrow flexing.

Longer inserts act as an internal footing ,  so if you tuned with a 1 inch insert and switch to a 2 inch your arrow should act stiffer (just like an external footing) you may have to increase point weight or length .  As far as breaking I foot all my arrows mostly with 2 inches of 2117 (for gt trads 600/500) [attachment=1,msg2924646] and 1/4 footing at nock end . It does not save all from breaking but it helps. 
The external footing does not change spine if it's the same length as the insert. 2117= 12 grns per inch