SHOOTING
Trust but verify. Always validate your MPBR calculations at the range.
size of the pipe being equiv-
alent to the size of the target
animal’s vital zone. The flight
path of the bullet grazes the
top of the pipe and drops to
the bottom of the pipe at the
max point plank range.
As I mentioned earlier, an
added benefit to MBPR us-
age is the simplicity and the
reduction of potential error
in the heat of the moment.
Bullet Drop Compensator
(BDC) reticles, rangefinders,
ballistic calculators, and drop
charts are all great tools to
have, and definitely serve a
purpose at the right time, but
often, in the heat of the mo-
ment, knowing you can aim
quickly and simply pull the
trigger is peace of mind. It’s
also invaluable for young or
inexperienced hunters who
can easily get overcome by
the excitement of the situa-
tion, or should you not want
to incur the added expense
that comes with BDC scopes,
high end rangefinders, and
ballistic calculators. What
could be more simple than
placing the crosshairs in the
middle of the vital area and
pulling the trigger?
In a perfect world, we
48
WESTERN HUNTING JOURNAL
would all shoot with per-
fect precision but we should
acknowledge that both our
equipment and ourselves are
inherently limited to some
degree. We can get some es-
timation of that at that range
by finding out what kind of
groups our rifles will shoot at
100, 200, or 300 yards. Inevi-
tably, though, you will want
to build in a margin of error
to the size of those vital areas
listed below when calculating
the MPBR for an upcoming
hunt. If you are pursuing elk,
for example, you can see that
they have around a 15-inch
vital area, but if at 300 yards,
I am shooting a three-inch
group, I will likely be conser-
vative and use 80 percent (or
12 inches) of that as my target
size in the calculation. Refer
to the sidebar and photo il-
lustrations for a clearer refer-
ence.
So how does one calculate
their own specific MPBR? The
first step is to gather the nec-
essary information you will
need to make the calculation.
That includes the ballistic co-
efficient of the bullet you’re
shooting (it will either be on
the box or on the manufac-
turers website if you’re shoot-
ing factory ammunition), the
velocity at the muzzle of your
load (this will also be on the
box if shooting factory am-
munition but it’s best to veri-
fy with a chronograph if at all
possible in order to maximize
the accuracy of the calcula-
tion), and bullet weight. Once
you have all that information,
use an online calculator. A
quick search online will point
you in the right direction. One
that I’ve used is found at www.
shooterscalculator.com. Hor-
nady has a nice ballistic calcu-
lator on their website (www.
hornady.com) as well.
For most common car-
tridges that are popular today,
the zero range is going to be
in the 200- to 300-yard range
so you can start by setting the
zero range somewhere in that
range. Then, look at the result-
ing drop table to see if you are
getting a trajectory over the
line of sight of half the size of
your assumed target size.
To help illustrate this, let’s
look at a popular 6.5 Creed-
moor load for mule deer. Al-
though muleys have a 10- to
12-inch vital zone, I would
base my target size on some-
thing smaller than that taking
into account some inevitable
human error during the shot
process. Figuring on that 80
percent we discussed earli-
er gives me an 8-inch target
zone. If I start by placing my
zero range at 250 yards, my
bullet’s trajectory only rises
3 inches above the line of site
before falling to that range
so I know I can still move my
zero range out. At 275 yards,
the drop table shows me my
bullet’s trajectory will be 4
inches above line of site at
150 yards, dropping back to
zero at 275, and then I can see
I drop 4 inches below line of
site (the bottom of my target
size) at 325 yards, which is,
then my MBPR. Anything in-
side of 325 yards, I hold dead
center of the deer’s vital zone,
execute a solid trigger pull,
and I’m packing meat back to
the truck.
If we look at a similar sit-
uation, this time chasing elk
in the Rockies at 8,000 feet in
elevation with the time-test-
ed .300 Win Mag and a 200g
Accubond bullet, I would
start my calculations with
an 11-inch vital zone target
size (80 percent of the elk’s