As I mentioned a week or two ago… I really want to see if there is something behind the EFOC arrows that it’s all the rage these days (and whether it is worth the extra cost and effort) I built an arrow on specs and recommendations, but sometimes, when you play outside the known guidelines, things do not always go as expected…
In the previous post, I commented that I will go for a GoldTip Velocity 340… This did not work.
The extra weight in front just left me soft in the spine, even though I was shooting with a softer cam (the Bowtech “Comfort” setting on the module), so I had to go to 300… which was just a bit stiff, and added shaft weight (8.2gr vs 8.8gr) so I added more weight to the front… which worked out perfectly!
I now have the option of shooting 100gr or 125gr points (and even a 200gr doesn’t fly badly) and the grouping over distance, noise and flight in wind is all good… I think we have a winner! Not quite so high on the FOC percentage as I wanted, but do-able.
So what did I do?
Firstly… the new shaft weight is 8.8gpi… and that is from a 300 spine GoldTip Velocity. I tried a softer spine (and a very soft spine, even going to a 400) but I kept tearing tail right on paper and impact left on target. That was not going to work, unless I do some crazy bow adjustments which I simply did not think is a good idea – so 300 spine it is.
From there I cut it to 29” and made sure edges are straight, and glued in a 150gr insert (well, a 100gr brass insert, and 50gr FACT weight.
I made two of these, one with fletches (using the slightly lighter VaneTech HD vanes) and one bare shaft for tuning. Shot both through paper (slight tail high) and off to the range. The bare shaft tuning was done on 20yds and although the height was consistent, my bare shaft was about a hand’s width to the left. My yoke tuning was ok, I felt, so I simply moved my rest ever so slightly in. Two more very slight adjustments, and the two was consistently touching. Seems every adjustment here was “slightly”!
(Just out of interest, I wanted to see what the soft spine would do, and it was good on height, but consistently left)
Happy with the results so far, I went and made a few more arrows, half with 100gr points and half with 125gr.
Here are the results of that test on my Bowtech BT-Mag at 70lbs (29” draw – comfort setting):
Control (Standard GoldTip Kinetic 340):
125gr point, 472gr = 12% FOC
at 280fps (82.2KE / 0.586 slugs)
EFOC (GoldTip Velocity 300 + 150gr inserts)
100gr point, 534gr = 20.7% FOC
at 264fps (82.7KE / 0.625 slugs)
125gr point, 560gr = 22.8% FOC
at 259fps (83.4KE / 0.634 slugs)
Ok… so 21fps down from my control arrow… should this matter?
What do I Win?
- Kinetic Energy
- Less noise
- Better broadhead control
- Hopefully some good penetration?
What do I lose?
- 21fps in speed…
Is that a concern? I really do not think so… you just need to pay a bit more attention to animal behaviour… Is it worth the trade-off? I do think it might be, but I will have to spend the season with them and decide.
Which brings me to accuracy and forgiveness… How do they fly?
I took them out and shot at 55yds against my standard Kinetics (which I know groups pretty well) They definitely do not fly worse, that’s for sure. They feel slightly slower, but they fly beautifully and impact solidly! I am happy, they will work… I really feel I have a good arrow if another archer shooting on the range walks up and asks: “…What are those?”
I am really glad I didn’t go with the 340 spine arrows. Now to set up a sight tape, broad head tune, and go find something to hunt!
The only real question that now remains is whether the extra cost and effort to make these are worth it?