All I know is I got my 2117's glued on my 15/35's with No problem what so ever...It's good to know there are several other sizes that work just as good so a 15/35 and a 35/55 G.T can take about 4 different aluminum footings so the choice is with whatever you may have or can get..I was fortunate to trade some Easton nocks for some 2117's and all went well footing mine...
I had found I had to deburr them well and chamferr then run the bore brush through for a clean fit...I am no expert on Aluminum sizeing charts but somewhere I found a chart Charlie Lamb had made up with what shaft size fits what carbon and from that chart and a friends advice I chose the 2117's..
It worked well but if I had some 2216's like Shawn told me to try I would of went with those but my trade was alredy in the making at the time...
Thanks to Shawn and everyone helping myself and those that were asking and letting us know what worked for them...