I found this on Muzzy'sHow To Tune For Broadheads
Broadhead tuning requires a bow that is properly tuned in order to achieve accurate and
consistent arrow flight. Shooting form, proper center shot and proper nocking point must be
achieved before any broadhead shooting takes place. Helical fletching is vital for consistent and
accurate fixed blade broadhead flight. We highly recommend shooting helical fletching with any
broadhead. You want to spin the arrow in flight to stabilize the arrow/head, similar to rifling in a
gun barrel.
Fletching clearance with the bow and rest is vital as well and often overlooked by many shooters
in the tuning process. Fletching contact (even with feathers) can present as incorrect center shot
or nock point adjustment and cause mass confusion during the tuning process. Incorrect arrow
spine can also show center shot problems for finger shooters and nocking point or rest height
problems for release shooters. Finger shooters put a horizontal torque on arrows and release
shooters exert a vertical torque upon arrow release. Drop away rests can be very beneficial to
eliminating or reducing these problems, but proper rest adjustments, spring tension and
nock/fletch orientation can significantly reduce these as well.
Broadheads must be perfectly straight and aligned on the arrow. Broadheads should be
assembled on the arrow, tightened and spun to check for straightness. Occasionally, inserts or
outserts need to be turned in order for the broadhead to spin properly. 2-part epoxy is good for
this purpose as its slow cure time allows the archer to check the arrow/head as the epoxy begins
to harden.
Broadheads should be turned on the arrow as the epoxy thickens until the arrow/head spins true.
Then stand the arrow up straight for the glue to cure. Hot melt adhesive is also useful (especially
for aluminum arrows), but working time is very short and occasionally must be reheated to
achieve a true spin. All of these problems must be addressed prior to an archer tuning
broadheads. If all of these problems are corrected, broadhead tuning can be a snap.
Typically compound bows are tuned to shoot a bullet hole through paper and recurves/longbows
are best tuned to shoot a bare shaft perfectly straight. Bareshaft tuning will work very well with
compounds and give you the best fine tune if the shooter has good form and is using a drop away
style rest. Normally these methods are done at 6 feet for paper tuning and 10 yards for bareshaft
tuning. Generally, perfect broadhead flight can be achieved through these methods. If good
broadhead flight is found, then arrows are shot at 20, 30, 40 yards, etc. and checked for
broadhead grouping.
When broadheads group well, then consistent arrow flight is achieved. Occasionally, some minor
rest and nocking point adjustments may be necessary to achieve good grouping. Broadhead
groups that deviate high and low can benefit from minor nock or elevation adjustments.
Conversely, groups that show a horizontal deviation can benefit from minor center shot
adjustments.
In both situations, adjustments should be made minutely in 1/16in. increments or less, in either
direction, until groups close and become more consistent. One important point to remember,
adding a broadhead to the end of the arrow is like adding small fletchings, any angle that the
arrow leaves the bow is generally the direction the arrow will want to follow until the fletching is
able to control and direct the flight of the arrow. If everything is in a straight line, straight and
consistent arrow flight is easier to achieve.
Many bowhunters still believe that consistent grouping of field points and broadheads into the
same sight point is possible and expected, this sometimes happens, but with today’s faster and
harder shooting equipment, this can be difficult. I, personally have had only a few bows that
would group field points and broadheads together and all of those were slower energy cam type
bows generally shooting under 260 f.p.s. and all of my recurves and longbows. However, with
the advent of drop away rests, this has become much easier and more expected and normally
these high performance bows will group both points right on or very close.
If a bowhunter wishes to attempt this, adjustments can be made to rest height and center shot to
move the groups closer together. Broadheads react to the direction in which they are launched
much more than target tipped arrows. If broadheads group in a different spot than the target
points, adjust the rest in very small amounts in the direction the target points are hitting at. In
other words, move the broadhead group to the target point group. If your broadhead hit to the left
of the field points, move the rest to the right, if the broadheads are low, move the rest up. Just
remember to make small adjustments when moving and pay attention to broadhead grouping and
stop when they start to deteriorate. In that situation, just adjust for the best broadhead group and
readjust your sights.
Broadhead tuning can be an arduous affair or can be very simple. A lot of time and patience is
necessary to achieve this task, but as bowhunters, we owe this to the animals we hunt and our
reputations as hunters and sportsmen to ensure that the most efficient and humane harvest is
achieved and one that provides us with adequate sign to trail the animal and a short and humane
harvest.
Best wishes and good luck in your tuning!
Yours in responsible bowhunting,
Mark Land
Muzzy Technical Support Specialist site