Pennsylvania Game News - August 2020 - 56

Measured in grains, arrow weight is
influenced by arrow diameter, wall thickness and shaft material. An arrow weighing 5 or 6 grains per inch of length (GPI)
is considered lightweight. A midweight
arrow typically weighs 7 to 9 GPI; a heavy
arrow, 10 or more GPI.
Different arrow weights and other
setup variations achieve different results.
My 29½-inch, 400 spine FMJ hunting arrows weigh 10.2 GPI, and when
fitted with inserts, vanes, lighted nocks
and 100-grain broadheads, each arrow
carries about 455 grains of total arrow
weight. I've found this combination
has produced more pass-throughs and a
somewhat quieter shot when compared to
a lighter arrow.
Meanwhile, my 29½-inch Carbon
Express 250 spine Maxima Red SD
arrows weigh 8.1 GPI and when fitted
with half-out inserts, vanes, lighted nocks
and 100-grain hunting heads, each weighs
about 415 grains. With this combination, I
gain a little more velocity without sacrificing significant momentum.
These examples help to explain the
relationship between arrow weight and
velocity. The lighter the arrow, the faster
it is.
That said, each arrow slows continually
on its path to the target, but lighter arrows
decelerate more. That means heavier
arrows retain more of their energy and
usually penetrate deeper.
Quieter-shooting heavy arrows can
provide an advantage in the field. Staying
undetected is important when hunting;
there's no such thing as being too quiet
when a whitetail is standing 15 yards
away. And in my experience, a heavier
total arrow weight and a quieter shot
seem to minimize string-jumping by deer,
which can lead to bad hits.
On the downside, heavy arrows are
56

slower and result in a higher trajectory
than lighter ones at distances. That might
require additional sight pins or make
pinpointing distance to the target more
important, because misjudging by a few
yards can result in a clean miss or worse,
a wounded animal. A more-arching trajectory also might expose a flying arrow
to more brush - on the ground and in
the forest canopy - that could send it off
target.
While the give and take with arrow
weight is obvious, also consider a lighter
arrow doesn't absorb as much of the
bow's energy, so that residual energy
dissipates into the bow and shooter
as unwanted vibration, which causes
additional noise. Most manufacturers
offset this with technology - including
installing high-performance fibers at
critical locations - to dampen vibration
and reduce noise.
Manufacturers also have begun offering the best of both regarding arrow
weights.
Micro-diameter arrow shafts, which
have about half the surface area of a largerdiameter shaft, have become popular
because they're less likely to be affected
by crosswinds. Smaller-diameter shafts
also have less drag on the arrow, increasing the likelihood of pass-through shots
on big game.
Keep in mind, though, these arrows
still weigh about the same as largerdiameter shafts.
Take all of this into consideration when
deciding which hunting arrows to use.
It's not all about speed. In most hunting
situations, arrow mass, and the weight
that comes with it, is essential to lethality.
And with any setup, getting arrows to
fly perfectly and penetrate deeply helps
ensure the outcome we all want and makes
us more proficient along the way.

Pennsylvania Game News - August 2020

Table of Contents for the Digital Edition of Pennsylvania Game News - August 2020