Click pictures for a larger version.
ACE skeleton buttstock on Jeff's DPMS lower.
Tactical Solutions Karma-7 sound suppressor.
Timney Trigger makes long-range accuracy easier to achieve.
Since being standardized as the 300
Blackout by SAAMI, the 300 Whisper cartridge has really
taken off in popularity. The Whisper series of cartridges
developed by J.D. Jones of SSK Industries has been around for
many years, but only enjoyed a relatively small but loyal
following. However, Mr. Jones’ work in developing the 300
Whisper and the others in the Whisper family is what started the
search for a multi-purpose cartridge for both hunting and social
work, that could be used with subsonic and supersonic loads in a
variety of weapons. The ability of the 300 Whisper and Blackout
to perform admirably in the standard AR-15/M-16/M-4 series of
weapons has led to its popularity. The cartridge uses standard
AR magazines, standard 5.56mm AR bolts, and standard AR gas
system. Also, unlike the attempts to chamber the 7.62x39mm
cartridge in the AR, the Whisper/Blackout works extremely well
in the AR. While there are slight differences in the final
specifications of the Blackout as compared to the Whisper, for
the purposes of this review, they are interchangeable. That does
not mean that every 300 Whisper rifle ever built will work well
with the Blackout ammunition, nor the Blackout with every 300
Whisper cartridge, but it is generally understood that one can
use both 300 Whisper and 300 Blackout in a 300 Blackout rifle,
but only 300 Whisper ammo in a 300 Whisper rifle. Smith &
Wesson marks their weapon to work with both, and that is what we
are reviewing here. Also, I want the reader to be aware that
there is a family of Whisper cartridges, from 300 up through 50
caliber (510 inch bullet diameter), but in this review, “Whisper’
will be referring to the 300.
I reviewed the 300
Blackout rifle from Advanced Armament Corporation a couple
of months ago, but in this review, we will be looking at the 300
Whisper/300 Blackout upper for the AR-15 that is available from
Smith & Wesson, along with some very specialized premium
ammunition from Lehigh Defense that was not available to me in
my previous review. The S&W upper assembly comes complete
with a sixteen-inch M-4 profile barrel, quad rail, bolt carrier,
bolt, and everything else need to quickly attach to any standard
AR-15/M-16/M-4 lower receiver. I attached the upper to a DPMS
lower that normally has my Alexander
Arms 50 Beowulf upper attached.
Since my earlier review of the 300 Blackout,
I have discovered Lehigh Defense ammunition. Lehigh makes both
subsonic and supersonic ammunition for the 300 Blackout/Whisper,
and the ammo is loaded with specialized bullets built for
specific applications. The Lehigh ammo is loaded with Controlled
Fracturing bullets that are designed to come apart after impact,
with the pieces radiating into the target. Other Lehigh bullets
are designed for maximum diameter expansion, with pedals folding
out from the bullet shank for maximum tissue damage. Lehigh
subsonic ammunition is built to expand at low impact velocities.
These heavy bullets are machined to expand rapidly, producing
pedals and/or fracturing like the supersonic loads, for maximum
effect on target.
I fired the Lehigh ammunition on targets from
twenty-five out to over 600 yards. As expected, the trajectory
of the subsonic loads made hitting at distances greater than
about 200 yards a challenge, as they are intended for
close-range use from a suppressed weapon. However, even at
greater distances, once I had figured out the trajectory,
hitting the target was not too difficult, but was probably a
waste of good ammunition in that effort. The supersonic Lehigh
ammunition performed admirably out to the farthest shots
attempted. Hitting steel rams at 547 yards was no challenge at
all, shooting from a Target Shooting,
Inc. Model 500 rifle rest. I ran the S&W upper with a
Tactical Solutions suppressor attached at all times. All Lehigh
subsonic Whisper ammunition is loaded to a nominal velocity of
1040 Feet-per-second (fps), in 300, 338, and 510 Whisper
cartridges, but higher velocities were recorded from this
sixteen inch barrel.
All accuracy and velocity testing was done at
an elevation of 541 feet above sea level, with temperatures in
the 105 degree Fahrenheit range, with a light breeze and a
relative humidity of twenty-seven percent. All accuracy testing
was done firing from a solid bench using a Target Shooting, Inc.
Model 500 rifle rest. For accuracy testing, I used a Leupold
Mark 4 4.5 to 14 power scope set to the highest magnification.
The scope was attached using an Accushot one-piece base.
Subsonic ammunition testing was done at fifty yards, and
supersonic ammunition was tested for accuracy at one hundred
yards. Velocities are listed in the charts below. Velocities are
listed in feet-per-second (fps). Bullet weights are listed in
|Lehigh Defense Maximum
|Atlanta Arms Pink Tip
As can be seen in the charts above, most of
the subsonic ammunition was not subsonic from this sixteen inch
barrel. The 300 Whisper/Blackout cartridge was developed for use
in short-barreled rifles (SBR) and submachine guns. Ideally, a
barrel length in the nine inch range offers optimum performance
with subsonic ammo, and it is for those shorter barrels that the
ammunition is loaded. In the shorter barrels, the Lehigh
ammunition runs at approximately 1040 feet-per-second (fps), and
is much quieter at that speed. Having no SBR handy, my testing
was limited to this sixteen-inch carbine. The supersonic really
interests me, as I see this as a very good choice for a
relatively quiet, low-recoil hunting cartridge. The supersonic
300 Whisper/Blackout is pretty much equal in power to the
7.62x39 and 30 WCF (30-30 Winchester)
cartridges, and has plenty of power to harvest Southern
Accuracy from the S&W upper was very
good, especially with the supersonic ammunition. In fact,
accuracy was excellent with all of the supersonic loads tested.
The heavier subsonic loads showed signs of instability at 50
yards, but still, accuracy was acceptable at that distance. I am
really anxious to try that Lehigh specialty ammo on whitetail
deer this coming Fall. If it expands like the fired bullets
which I have seen, it should be very effective.
In addition to my accuracy testing here in
Tennessee, I carried the Whisper to the NRA
Whittington Center near Raton, New Mexico last month for
some long range shooting. The NRAWC is a great place for
shooting at distance, as the arid ground makes spotting misses
easy, for windage and elevation correction out to as far as one
wants to shoot. For the 300, I limited my shots to a maximum of
600 yards with the supersonic ammo, and 300 yards with the
subsonic. For the slow stuff, hits on random targets like small
rocks and such were pretty easy to make out to around 200 yards,
but after that, the trajectory is such that it would take a much
better shooter than I to guarantee a hit. This is not a
derogatory remark regarding the cartridge, the rifle, nor the
ammunition. The combo performed very well. The subsonic ammo is
designed for use from short to moderate range. Again, think
short-barreled rifle or submachine gun. However, I was
pleasantly surprised by the long range performance of the
supersonic 300 ammunition. Hitting the steel rams on the
metallic silhouette range was extremely easy from the Target
Shooting, Inc. Model 500 rifle rest atop a solid bench. These
rams sit out at 547 yards (500 meters for you tactical types),
and the 4.5 to 14 power Leupold Mark 4 took all the guesswork
out of holdover at that distance. Shooting standing offhand at
targets of unknown distances out to 600 yards was again plenty
easy, when I did my job well pulling the trigger.
The sound signature was greatly reduced,
using both the subsonic and supersonic ammunition, by the
Tactical Solutions Karma-7 suppressor. The S&W upper is
already threaded 5/8x24 TPI, so installation was as easy as
screwing the brake off of and the can onto the muzzle. As noted
above, most of the subsonic loads were supersonic from the
sixteen inch S&W barrel, but still noise was
well-suppressed. While the Lehigh Defense subsonic ammunition is
obviously built to be fired from a SBR or sub gun, it is still a
good choice for longer barreled rifles and carbines. I know of
no such plans from Lehigh, but with more sixteen inch carbines
hitting the market, they maybe should consider a subsonic load
for these longer barrels, in addition to the ones which they now
The 220 grain Remington ammo was subsonic
from the S&W barrel, and the sound signature greatly
reduced. Of course, a handloader could tailor his loads to
whatever powder charge was needed to achieve the desired
velocity. The 300 Whisper/Blackout seems to be taking hold, but
time will tell if it achieves the popularity that it deserves.
The cartridge is a very versatile one, having applications in
the hunting field, as well as its usefulness as a military
cartridge for submachine guns.
Check out the extensive line of Smith &
Wesson firearms and accessories online at www.smith-wesson.com.
For the location of a Smith & Wesson
dealer near you, click on the DEALER FINDER at www.lipseys.com.
To order a Smith & Wesson firearm online,
go to www.galleryofguns.com.
For high performance subsonic and supersonic
300 Blackout ammunition, go to www.lehighdefense.com,
For quality optics, and a specialty premium
riflescope set up for the 300 Whisper/Blackout cartridge, go to www.leupold.com.
For more information on the 300 Blackout and
300 Whisper cartridges, go to www.300aacblackout.com
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Click pictures for a larger version.
Leupold Mark 4 scope with illuminated reticle.
Factory ammo tested.
Subsonic ammunition (L to R): Lehigh Defense 170, 186, and 200 grain, Remington 220 match.
Supersonic ammo (L to R): Lehigh Defense 140 Controlled Fracturing, Atlanta Arms 125 Pink Tip, Remington 125 match.
Lehigh Controlled Fracturing (top) and Maximum Expansion bullets
(bottom) have longitudinal machined slits to promote rapid expansion at low velocity.