Awesome E.F.O.C Idea


So I’m looking for a way to get a certain arrow set up. I want 700 grains total weight with a 30% extreme f.o.c set up. I need to keep my 140 grain  broad heads as i have over 100 of them. I also like being able to use judos that are the same weight as my.

Here is what I have come up with. 2 brass 100 grain inserts. I grind down the end on one so that it would fit completely into the shaft. I used a finish nail and cut it to the length  i needed. Put the finish nail into one insert then slide the other insert on to the opposite end of the nail so that the ends of both inserts face each other. Then I put one punch in one end and the other punch in the opposite end and hit with a hammer to bend the nail locking the 2 inserts together.  Simple, quick, and effective.

This gives me a total insert weight of 185 grains.

My arrows im testing are my goldtip 3555 and some 5575 and so beman 340 ics. all arrows are cut to 27 inches. my longbow is a 63# at 26″ longbow and I pull about 25.5 inches. So far my bare shaft testing has me leaning really heavy on the goldtip 3555 flying the best. The 340s are way too stiff. the 5575 are just a hair to stiff. Still need to fine tune the testing. I want to stay with a 27″ arrow as I have a ton of them in a bunch of sizes. (don’t want to cut to tune).

So my 3555 set up (if i go that route) makes a 695 grain arrow with 30% E.F.O.C set up as follows 27″ GT 3555 shaft, 100 grain brass insert, extra 100 grain insert, 100 grain steel adapter, 140 grain head, and the knock.

Added bonus is the extra insert will work like a poor mans internal footer and help strengthen the shaft as the total insert length is about 3 inches with both inserts together.

I’m pretty excited to do more testing with this set up.


  1. I like lead wire for weighting things, much heavier than nails and pretty cheap. 1/8″ wire weighs 37 gr/inch. Let me know if you want some to play with.

    • Thanks Rick. The nail is just to hold the inserts together. I mash the nail with the punches so they cant come apart. I will also epoxy both inserts when i install them for good after testing.

  2. Jason,

    Amazing what a touch shorter draw/arrow length does to up spine. I draw 28 3/4 and have to get to 29.5″ arrow for a comfortable over hang.

    when I got my Bigfoot, I had to jump up in spine even though my new bow draw weight was lower. Kirk does harness his innate power better than some!

    I got some GT7595 given to me that tuned out well…I had to leave them a touch longer… but no biggie…spined them right in.

    Troy B told me after testing hundreds of dozens of every mfg building competitive arrows for stick and wheel shooters, GT’s have some high variance in a given dozen of shafts on spine. I tuned each and every arrow…cutting till I got each one right. I had 3 that were screwy… but with 1/8″ off one, 1/16″ off another and 1/4″ off a 3rd, they all dialed in. Had to # them and keep a table shooting to be sure, but it was worth it.

    Too bad brass inserts aren’t 8-32 threaded thru…piece of 8-32 all thread and some epoxy and you’d be all set screwing them together.

    I’m surprised you’re not using JB Weld or something to affix them together. I’d think sooner or later they’d rattle apart!

    Nice to see some new ideas from you! You’re always thinking and experimenting!


    • Davie,
      It shocks me that a 3555 with that much weight up front was the one that is tuning the best. But i figure it has alot to do with the length of the 2 inserts stiffening the spine.
      I didnt JB weld them together as i figured the nail gets mashed with the punches and i can pull them apart with pliers, then (after testing is done) I will also glue both inserts in the shaft. hopefully the nail and the gluing both inserts will hold them still and quite.

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