Hk MP5 - Global Defense Initiatives

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SUMMER 2014 /// Volume Twelve, Number One
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SPOTLIGHT >>>
By Cameron Hopkins ///
kiNG of thE
MouNt
B
igger is not always better. A
comparatively small player in
the big world of quick-detach
scope mounts, a company out of Southern California is producing the most
highly engineered optical sight mounts
for 1913 rails I’ve ever examined. Better
known by their acronym, GDI, Global
Defense Initiatives is by far the best
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COMBAT TACTICS /// FALL 2013
maker of mounts you’ve never heard of.
GDI was born on the battlefield
(founded by a former Navy SEAL) and is
now located in Temecula, Calif., not far
from Coronado Island, in San Diego, the
SEAL base where founder Marco Gonzalez once served. The former frogman
designed and built GDI’s first optical
mount for the M1A (M14/EBR) battle
//////
FROM AADLAND TO
ZEISS, WE COUNTED 63
DIFFERENT BRANDS OF
MOUNTS, BUT ONE ROSE
TO THE TOP. IT’S CALLED
GDI, AND LIKE THE NAVY
SEAL WHO STARTED THE
COMPANY, THERE’S NO
COMPROMISE.
rifle, which was adopted and fielded by
Airborne units. GDI’s follow-on mount
design for the Trijicon ACOG was
adopted by perhaps the most discriminating of all when it comes to marksmanship— the U.S. Marines.
GDI mounts are absurdly well made,
machined by CNC machines from solid
bar stock (either aerospace aluminum
or stainless steel). The auto-locking
levers are adjustable for
tension (only requiring
a standard screwdriver,
found on any Leatherman) and feature the
slickest, most positive
“safety lock” of any mount
I’ve ever tested. Known as
the Auto-Locking Quick
Detach (ALQD™) System,
this is the heart of GDI’s
patent-pending design—
the ALQD lever system
self-locks with a reassuring “snick” and stays
locked until you slide the
spring-loaded, serrated
tab to unlock it.
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SPOtLiGHt
SPOTLIGHT >>>
GDI MOUNTS
≈ The P-ROM (for Rifle Optic Mount) is beautifully machined from
billet aluminum and features a pair of beefy quick-detach levers. It
comes in 30, 34, & 35mm main tube diameters and can be adjusted
to fit any 1913 rail, to spec or not.
THE ORIGINAL GDI
MOUNT WAS DEVELOPED TO ADDRESS
'FAILURES ON THE
BATTLEFIELD'
Quality is not cheap. Their most
expensive model is $565 for a duallever, one-piece mount for a tube scope
(30mm, 34mm, and 35mm diameters,
with or without 25-MOA cant), which
compares to a similar LaRue model
priced at $268. Other brands can be
found under the $200 price point.
“Our products are more expensive,”
Gonzalez acknowledges. “Our mounts
are combat-proven, with the best
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COMBAT TACTICS /// SUMMER 2014
return-to-zero in the industry. Our QD
locking levers don’t break off. All of our
A-L-Q-D mounts are machined from
solid stock. No castings. And, of course,
we are fully American made and veteran owned.”
Gonzalez is too much of a gentleman to name names regarding which
brand(s) of levers might be snapping
like twigs, but he says the original GDI
mount was developed to address “failures on the battlefield” of another brand
with exactly that issue.
Gonzalez is the first to admit that
GDI mounts are not for casual use.
“If you’re mounting a Weaver scope
on a 10/22 rifle, you don’t need our
mount. But if you’re going into combat
with your Mil-Spec-tested M4 that you’ll
trust your life to, you want the very best
mount, one that’s not going to break,”
Gonzalez adds.
The first GDI mount to gain U.S.
military acceptance was the G1-OSM
(Optical Sight Mount) for the M1A
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(M14/EBR). It was initially adopted in
2004. From there, more models followed
for Aimpoints and Trijicon ACOGs, but
as every new model was developed over
the intervening years, the emphasis
was always on, for lack of a better term,
“martial mounts.” None were made
to hit some magic $199.99 retail price
point; all were made without compromise, and they cost what they cost.
I first ran across GDI mounts about
six years ago. The model was engineered
and designed for the M240G machinegun that the SEALs, Army, and Marines
issue. Anything that weighs 25+ pounds
(without a 100-round belt of .308) is
going to get banged around, thrown,
drug, kicked, shoved, rattled, and beat
to hell. Show me a Two-Forty Golf with
a lick of finish on it, and I’ll show you an
unissued gun.
Gonzalez was undeterred. His ruggedized mount took anything the Golf
could churn up— or, more to the point,
anything the guys who run the gun
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SPOTLIGHT >>>
GDI MOUNTS
could inflict on his hapless mount.
Two things came to light from
GDI’s machinegun mount. First, even
the most destructive animal on Earth,
a Marine machinegunner, could not
break a GDI mount. Second, not a single
GDI mount was ever replaced in the
field for breakage of any sort.
ZERO DARK THIRTY ::::::::::::::::::
Then there’s the issue of zero. The Holy
Grail of a detachable mount is a true
and repeatable “return to zero” of the
optic after removing and replacing
it on a weapon. Every manufacturer
on the market— from the cheapest of
the cheap to, yes, the expensive big
names— all claim that their mounts
“return to zero.” But what exactly does
that mean? And how do you test it?
Obviously, it means that the optic in
the detachable mount retains the same
point-of-impact even after loosening
the attachment lever, removing the unit,
replacing it, re-tightening the lever, and
then shooting.
But is that what “return to zero”
really means?
Not quite. There’s no such thing as
a removable, replaceable mount with
absolutely no impact shift. What the
manufacturers really mean is there’s no
discernible shift.
In laboratory testing by an independent firm, GDI mounts were removed
and replaced repeatedly with a deviation of 0.01 MOA, which is completely
undetectable on even the most accurate
military rifles. The only rifle that can
tell the difference in one-one-hundredth-of-an-inch deviation is a highly
Ω The R-COM (for Combat Optic Mount)
is made for several models of the ACOG
sight from Trijicon. The ALQD lever
features a self-locking tab to prevent
accidental opening.
≠ Into the "Why Doesn't Everyone Do
That?" category comes GDI's see-through
mount for a mini-Aimpoint. The bored-out
mount allows you a wider field of view,
plus reduces weight.
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COMBAT TACTICS /// SUMMER 2014
customized competition benchrest rifle.
The variance is outside the inherent
accuracy of all but the most esoteric of
“rail guns” (the ungainly behemoths of
the benchrest world that can truly shoot
into the hundredths).
What about the real world? Relying on data supplied by GDI (as I don’t
have any such measuring capability),
the answer is 0.20 MOA. If you remove
and replace an optic in a GDI mount in
the field, you can be assured it will be
within two-tenths of an inch of its previous zero.
If you can hold that well.
If your rifle can shoot that well.
Two-tenths of an inch.
In combat.
Meaningless.
Call it “zero shift,” and no one will
know the difference. But not Gonzalez. What I find both admirable and
fascinating is that Marco Gonzalez,
alone among all mount makers, actually
tells the truth. His mounts do not retain
“perfect” zero. There is a measurable
variance of 0.01 MOA, as determined by
relentless field and lab testing.
The other 62 mount makers are
prevaricating. There’s variation in all
mounts! The difference is that other
makers have either never had their
products tested by an independent lab,
or they’re afraid to publish the results,
or they’re, well, lying. There is no such
thing as absolutely no-zero shift in
any brand or make of “quick detach”
scope mount held on by grip tension.
It’s physically impossible to secure a
tool-less, detachable mount with 0.000”
movement. Besides, a “perfect zero” is a
dubious “benefit” that only invites fallacious claims.
To claim a “perfect” zero retention,
the rifle would have to shoot into the
exact same hole. Even without removing the mount— just leave the optic in
place— who can fire two shots consecutively into the exact same hole, a
“perfect double,” on demand? Not me.
Add to the difficulty the fact that you
need to break your cheek weld and grip
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