If you follow this bow tuning guide you will be able to shoot almost any broadhead and have them hit with your fieldpoints out to 80 yards or more. That includes almost all fixed blade heads which I feel are more superior and definitely subject to less failures than a mechanical head. I say almost all fixed blade heads because there are a few out there that just don't fly well for me no matter what I do.
I've been shooting bows since I was a kid and got serious about 30 years ago when my state went to a draw for deer tags. After two years of not drawing a rifle tag I'd had enough and have been bowhunting ever since. But it wasn't until 2009 that I figured this all out and now I can take a bare shafted arrow with a fieldtip and hit a pie plate at 80 yards with my compounds. Before that it was hit and miss as far as bow tuning. Sure I could get good flight and yes I killed deer and elk but things were not as good as they could be. I'm kind of a perfectionist and do believe good arrow flight and a sharp broadhead is everything when it comes to a clean kill.
I know that 80 yards with a bare shaft sounds unbelievable so hopefully down the road I can get a video up to prove it. Any way, the bow tuning guide below explains exactly how I do it. It is best to read all the way through this first so you understand the process.
Bow Tuning Directions
I prefer arrows that weight over 400 grs total with about 7 to 7.5 grains a pound of bow weight to be about ideal. I have tried arrows that weigh less and they are faster but if things go wrong, they will sooner or later, and shot placement is not perfect, penetration sucks! I also have found that an foc of 13% or higher is more accurate than the standard 8 to 12% recommendation. I personally shoot arrows with an foc of 15% but anything from 13 to 18% will fly superb if the arrow is spined right. 15 to 16% foc and over 400 gr arrows is easily achieved with 125 gr heads in most cases.
I have generally found that the spine charts are on the weak side for most arrow manufacturers. You can verify this by buying two arrows that the spine chart recommends for your bow, most pro shops will sell you one arrow at a time. Generally you need the same arrow length as your draw. At least that's what I prefer so I can keep that broadhead out in front of my hand when at full draw. Or maybe a half inch short like my present set up. Install the inserts and the fieldtip of the head weight you want to shoot, do not install any fletching on one shaft but fletch the other. If you have any old fletched shafts laying around you could use that as the fletched arrow providing that the spine is the same.
TIP: On the bare shaft do not glue in the insert but use a piece of cellophane, I like a plastic bag, as a shim to hold the insert in tight. That way you can easily pull it out later. You can also run your set up through On Target 2 or Archers Advantage to find the initial arrow spine. I use the both setting for arrows and like to end up on the weak side of green to start.
I usually eyeball my center shot to start by lining up the string with the cam groves with an arrow on the rest. The string should center on the shaft as you do this. If the arrow is off to the right, move the rest to the left until everything lines up. Do the opposite if the shaft is to the left of what looks like center. You can usually just eyeball rest height by nocking an arrow and laying it across the rest. I like it to look like its straight with the shelf, not up or down. I know this is not very technical but it is close enough for now.
Now take the fletched arrow and sight the bow in at 20 yards. Then take the bare shaft and back up to 20 yards and shoot. If the nock end of that arrow swings to the left and hits the target to the right the arrow is to stiff. You will have to either use more head weight or a longer arrow to weaken the spine.
If the nock swings to the right and hits the target to the left it is to weak and you will need to add more head weight or shorten the shaft length.
If head weight or removing/adding head weight doesn't get the bare shaft to fly straight, you can move the rest in the direction the arrow is hitting the target. If hitting left of where you're aiming, move the rest left; if hitting right, move the rest right. Move it a little at a time, 1/32" is enough. If you end up going more than an 1/8", you are going to have to change arrow spine.
If the nock end swings down lower the nock point. If it swings up, raise the nock point.
Ok, hopefully at this point you have a bare shaft that flies straight at 20 yards, if you do back up to 30 yards and verify. If it flies perfectly or really close to straight, and you are hitting really close to what you are shooting at, then you should be able to shoot just about any broadhead with your fieldpoints.
However, you might have to make an adjustment if your broadheads are hitting to low or too high. Shoot three arrows with fieldtips at 30 yards, then shoot one with a broadhead. If the broadhead is low, raise the rest, if the broadhead hits high, lower the rest. Once they are together back out to 40 and repeat and so on as far out as you want to go.
For you guys that want to achieve perfect arrow flight with bow tuning out beyond 50 yards this is what you do.
Take that bare shaft and back out to 40 yards and shoot, then 50 and so on or as far as you are ever going to shoot. You will want to have your bow sighted in with the fletched shafts before you attempt this. One thing, it is pretty easy to achieve good arrow flight out to 50 yards but once you move beyond that things tend to get really touchy.
It is a really a matter of making fine adjustments out past 50 yards with head weight or shaft length. If it shows weak, lower head weight or cut shaft length. Stiff, increase head weight or use a longer shaft.
Once you get your bow tuning right, you will be able to shoot a bare shaft arrow at 80 yards and hit that plate. Your fieldpoints and broadheads will be right in there as well.
Bow Tuning Resources:
I've found this software program to be indispensable for my initial bow tuning. For instance, recently I sold my Diamond Fugitive to a friend of mine and set him up with an elk arrow prior to delivering the bow to him, he lives 240 miles away so I had to get it right. I used this software to find an arrow and bought them. Made them up and they flew beautifully with fixed blade broadheads hitting with fieldtips out to 60 yards, his last pin. I did have to cut 3/4" off his arrow length so its not perfect but it is damn close.
You'll need an arrow saw for fine tuning, especially out past 50 yards. If you end up with a weak bare shaft and don't want to decrease head weight the only way to stiffen the spine is to cut length. I usually cut a 1/4" at a time when long range bow tuning. Besides, if you have an arrow saw you can build your own arrows, which in the long run will save you a ton of money. I've had mine for over 20 years.
You don't have to have a jig but I would if you pick up an arrow saw. I prefer the Blitzenburger but any jig that will allow you to lay the fletch down with a helical is the way to go.
I've shot Blazer vanes for years but this year I tried these with some big 3 blade heads. 175 grains, 2 1/4" long by 1 1/8, non vented VPA Terminators. They're dead on at 80 yards. They're on with the Blazers too but I do like the added surface area of these vanes for long range shooting with big heads.