Gemtech PSR Installation guide

TM-PSR
OPERATION AND MAINTENANCE
OF SOUND SUPPRESSOR
MODEL PSR
Before using this suppressor,
be certain you have read and
understand this manual.
Manufactured by
GEMTECH
Div. of Gemini Technologies, Inc.
P.O. Box 140618
Boise, Idaho 83714
ISSUED:August 20, 2011

WARNING 
Because sound suppressed weapons make less
noise than non-suppressed weapons, it is easy to for-
get that they are still firearms. It is of vital importance
to remember that a sound suppressed firearm is just
as dangerous as a non-suppressed one, and the same
safe handling requirements apply.
TM-PSR
FIRSTEDITION August2011
Publishedby:
ATI Star Press
Antares Technologies, Inc.
P.O.Box 140618
Boise,Idaho83714
Phone:[phone]
COPYRIGHTNOTICE:
©2011 Gemini Technologies, Inc.
All rights reserved. The contents of this publication may not be reproduced in any
form or by any means in whole or in part without the prior written permission of the
copyright owner.

TM-xxx
OPERATIONALMANUALFOR
SOUNDSUPPRESSOR MODEL
PSR™(.338 Lapua)
Manufacturedby
GEMTECH
Division of Gemini Technologies, Inc.
P.O. Box 140618
Boise,Idaho83714-0618
Phone: [phone]
FAX: [phone]
GEMTECHPROPRIETARY
Thisdocument contains proprietary information of Gemtech and issub-
mitted to the receiver in confidence. Any reproduction, use and/or dis-
closure of this and/or any portion thereof is expressly prohibited with-
out the express written permission of Gemtech
CONTENTS:
GeneralDescription ........................................................................ P. 2
Ablatives......................................................................................... P. 2
Effectiveness .................................................................................. P. 2
SafetyNotes .................................................................................. P. 3
Physical Specifications................................................................... P. 4
AmmunitionRecommendations ...................................................... P. 4
InstallationofMuzzle Brake............................................................ P. 5
SuppressorMounting/Dismounting .................................................. P 7
Maintenanceand Cleaning.............................................................. P. 7
LimitedWarranty and Repair Policy................................................ P. 8

SOUNDSUPPRESSORMODELPSR P.
 WARNING 
Failure to follow installation and maintenance instructions
detailed in this manual can result in potential for serious
injury to the user and damage to the weapon. Firearm sound
suppressors are user attached firearm muzzle devices, and as
sucharesubjecttoimproperattachmentunlesstheproperproce-
duresoutlinedinthismanual are followed.
MANUFACTURER’S DISCLAIMER
The manufacturer is not responsible for improper usage of this
product. This product is potentially dangerous, and as such it is the
user’s responsibility to understand and implement its proper use. If
you do not understand the instructions in this manual, please con-
tact the manufacturer for further clarification.
GENERAL DESCRIPTION
Pleasetakeafewminutestoreadthis instruction manual and keep it in
a safe and convenient place. The model PSR sound suppressor was de-
signed specifically for use with rifles chambered for the popular .338 Lapua
cartridge. It is a rugged suppressor and mounts on Gemtech’s proprietary
muzzle brake supplied with the suppressor. This suppressor contains no
expendable parts. We recommend against cleaning the interior of the sup-
pressor.Thisinstructionmanual gives the necessaryinstructionsforinstalla-
tion and maintenance of this unit. The mount is supplied with a custom
threadprotector.
On special order, the PSR suppressor can be supplied in 100% tita-
nium at a weight savings of 38%.
USE OF ABLATIVE AGENTS (ARTIFICIAL ENVIRONMENT)
Donotfire this suppressor with anyforeignmaterialinside.Designedto
operatecompletelydry, introduction of liquids, greases, or other foreign ma-
terialscan cause abnormalpressuresandmust never beused.Any resultant
damageisnot covered under warranty.
OVERALL EFFECTIVENESS
The real limiting factor on the effectiveness of centerfire rifle suppres-
sors is related to the sound of the bullet in free flight. The free flight bullet
noiseisrelated to the generalbulletshapeandis also directly proportional to
2

SOUNDSUPPRESSORMODELPSR P.
thebullet velocity.The non-suppressedsoundpressurelevel of thiscartridge
isone of thehighestofthe small armsriflesotherthanthe .50 Browning.This
suppressor is effective in markedly reducing the sound of the muzzle blast,
making it difficult for an observer to determine the origin of the shot and
reducingthe needforshooterhearing protection.Thereisno wayofeliminat-
ing the ballistic crack (or sonic boom) of the projectile traveling downrange.
Byreducingthe muzzle blast, the target is unable toappreciate the origin of
theshotandusuallyperceivestheshotoriginatingfromdownrange.
Besidessoundsuppression,therearetwoadditionaladdedbenefitsof
a sound suppressor, which are seldom mentioned.The first is that a sound
suppressor is also an exceptionally effective recoil reducer, often reducing
recoil to less than one fourth of its original magnitude. The second is that a
sound suppressor is an effective flash suppressor, and when using a night
vision device as a sight, the use of an efficient sound suppressor is almost
mandatorytokeep the flash from causing excessive“blooming”ontheview-
ingscreenofnightvisiondevices.
Allmuzzleattachments, including suppressors, will change barrel har-
monics and standing waves due to the increased weight of the accessory.
Thisresultsin a slight change in point of impactwith the device in place and
usuallyimproves grouping.ThePSR suppressorandmount combinationhas
been carefully engineered to provide a consistent, repeatable, and predict-
able shift in point of impact. The degree of change in the point of impact will
varywiththespecificweaponandtherigidityofthebarrel. Extensive testing
hasshown no deleterious effecton the groupsize.
SAFETY NOTES
1. Always handle weapons in a safe manner and assume they are loaded
untiltheyhavebeencleared.
2. User installation or removal of the sound suppressor must be accom-
plished in accordance with the instructions contained in this book.
3. Any installation, or removal of the Muzzle Brake mounting system must
be accomplished by a qualified armorer in accordance with the instruc-
tions contained in this book.
4. Serious injury to the user may result from an improperly installed Muzzle
Brakeand/orsuppressor.
5.OperatingTemperatures: Duringuse, the PSR suppressor absorbslarge
quantities of heat from the burning propellant gases. This heat is dissi-
pated by radiation, convection, and conduction. The heat buildup is par-
ticularly noticeable during rapid fire, where the temperature of the sup-
3

SOUNDSUPPRESSORMODELPSR P.
pressor can cause minor burns after only a few dozen rounds. The el-
evated temperatures can pose a hazard to personnel and materials that
may contact the suppressor when hot, and the suppressor must be al-
lowedtocooltoambienttemperaturebeforehandling.
6. Only use the suppressor completely dry.
7. Before performing any installation or maintenance operation, always re-
movethemagazinefromthefirearm,opentheaction,andvisuallyascer-
tainthatthe chamber is empty andtheweaponunloaded.Failuretodo so
can result in potential for serious injury to the user and others in the
vicinity.
SPECIFICATIONS
Caliber: .338Lapua
Length: 10 inches
Diameter: 1.75 in.
Weight: 32ounces
Materials: Stainless steel alloys
Finish: Cerrocote(DesertTan)
Minimumbarrellength: 24inches
MountO-ring Viton, 1-3/16(OD)x 1(ID) x 3/32
AMMUNITION
Forall of our centerfireriflesuppressorsitis recommended that onlyfull
metaljacketed,factoryloadedhuntingammunition,orspecificmatch-grade
bulletsbeused. Some of the highly frangible jacketed bulletsusedinreload-
ingammunitionhaveatendencytohavejacketseparation,whichiswhywe
recommendtheuse of full metal jacketed bulletswiththe suppressor. Jacket
separationwill cause the bullet totumble while inthe suppressor whichcan
seriously damage the internal baffles and lead to suppressor failure. Be-
cause of this, damage caused by use of any bullet other than the above will
notbecovered under warranty if there is jacket separation.
ThePSRsuppressorisdesigned to use any commercially loaded .338
Lapuaammunition.Remanufactured,subsonic,orhandloadedammunition
is used at the user’s risk, and damage caused by use of this ammunition is
not covered under warranty. The .338 cartridge is designed for long-range
shooting,andusing subsonic ammunition will only reducerange,generatea
significantPOI shift, and maynot stabilize correctly. Itsuse is tobe discour-
aged.
4

SOUNDSUPPRESSORMODELPSR P.
INSTALLATION OF MUZZLE BRAKE MOUNT
This suppressor is attached to the rifle with ease on a supplied propri-
etary muzzle brake. Proper alignment and mounting of the suppressor is
dependent on the care and precision used during installation. The mount
telescoped back over the barrel 3.6 inches for increased stability.
1. The PSR muzzle brake mount attaches to threads on the muzzle of the
rifle.Unless specially orderedotherwise,themount is suppliedforabarrel
with3/4-24NEFClass 2 threads. Our experience has shown thatthreads
smaller than 5/8 inch are more likely to stress relieve the muzzle of the
weapon,introducinginaccuracy.
2.Contourand thread the muzzle of the rifle asspecifiedinFig1(nextpage)
forthemountwith 3/4-24 threads (Class 2A fit). For proper alignment, itis
essential that the threads be absolutely concentric with the bore of the
weapon and that there is a sharp shoulder at the rear of the threads 90
degrees to the bore axis. Barrel threading must be performed on a lathe
withthebarrelturned between centers. The barrel threading procedure is
critical, and errors will result in misalignment. Gemtech can thread the
barrelandgaugetheinstallation for a nominal fee.
3. For barrels of a diameter less than 7/8 inch diameter at the muzzle, con-
tact Gemtech for special instructions and/or mount.
4.Somehandfitting will be necessary in orderfor the muzzle brake tofunc-
tionproperly without the suppressor inplace.
a)The simplest is to trim the90 degree shoulder area onthe barrel while
in the lathe so that when torqued on, the mount will be oriented as
desired (see Fig 2, next page).
b)The second method istousedifferentthickness washers fromtheshim
set enclosed with the mount.
c) When utilizing either of the above methods for brake orientation, we
havefound that the processof finaltightening will rotatethe mount an
additional10-15 degrees.
5. Thread adhesives are not essential if the mount is tightened into position
with at least 30 ft-lbs torque. Blue Loctite (242) may be used.
6.Degrease all surfaces with acetone.Apply the spacing shim (if used)and
theappropriate threadadhesive.Screw onthemuzzlebrakeandtorqueto
25-30ft-lbs.
5

SOUNDSUPPRESSORMODELPSR P. 6
Fig. 1
Fig. 2

SOUNDSUPPRESSORMODELPSR P. 7
WARNING: Be certain the weapon is unloaded and the bolt
open before mounting or dismounting the suppressor.
SUPPRESSOR MOUNTING/DISMOUNTING
Mounting:
1. The mount supports thesuppressor at two points: thethreads at the rear
and the diameter approximately 1/2 inch back from the front.
2. The suppressor is screwed hand-tight ontothemuzzle-brake.Thereisno
need to use tools, and the friction of the O-ring in the mount will prevent
unscrewing.
Dismounting:
1. Dismounting is the reverse of mounting.
2. Gloves are recommended ifthe suppressor is hot.
CLEANING
The PSR suppressor is constructed of corrosion resistant materials,
and the high flame temperature reduces interior carbon buildup. We have
found no need for (and discourage) frequent or compulsive cleaning. The
majority of users never clean the inside of their suppressor. We strongly
suggestagainstanyattempt to clean the suppressor other than cleaningthe
threadsintherear ofthesuppressorandthemuzzle-brakemount.The mount
threadsandO-ringshouldbecleanedwithahydrocarbon-basedcleaner.In
addition, the outside of the brake portion of the mount must be cleaned of
accumulatedcarbon with a hydrocarbonbased cleaningagent. Ultrasonic
cleaners are not effective with hydrocarbon-based solutions. Water based
cleaners should not be used. Firing with liquid in the suppressor can result
inabnormal anderraticinternal pressures.Anydamageresultingisthe user’s
responsibilityandnotcovered under warranty.
HUNTING NOTICE
If hunting with a suppressor is desired, consult your local state Fish &
Game Department, as not all states permit hunting with a suppressor.

SOUNDSUPPRESSORMODELPSR P. 8
WARRANTY STATEMENT
Our "warranty" has been practiced since our personnel started in the
suppressor business in 1976, in a time before legalese and when a hand-
shakeandthissimplestatementsufficed:"Ifa Gemtech product breaks and
it'syourfault,we'llfix it for a fair price in a timely manner.If it's our fault, we'll
fix it quickly at no charge." This policy born of pride in craftsmanship and
honor has served us and our clients well for over two decades and will con-
tinueinGemtech'sfuture.
Thesmallprintfollows:
The Magnuson-Moss Act (Public Law 93-637) does not require any seller or manufac-
turer of a consumer product to give a written warranty. It does provide that if a written
warranty is given, it must be designated at “full” or as “limited” and sets minimum standards
for a “full” warranty.
As do most major firearms manufacturers, Gemtech has elected not to provide any
written warranty, either “limited” or “full,” rather than to attempt to comply with the provisions
of the Magnuson-Moss Act and the regulations issued thereunder.
There are certain implied warranties under state law with respect to sales of consumer
goods. As the extent and interpretation of these implied warranties varies from state to
state, you should refer to your state statutes.
Gemtech certifies that all sound suppressors manufactured by them are free of defects
in materials or workmanship, and that they meet manufacturing specifications at the time of
manufacture.
It is our intent that the customer be completely satisfied with the product. Certain Gemtech
products may be classified as ordnance and/or implements of war and are sold by us with
the specific understanding that Gemtech has taken every reasonable precaution in provid-
ing our customers with inherently safe merchandise, and that we assume no liability what-
soever for unsafe handling or operation by the purchaser or his agents. Gemtech assumes
no responsibility whatsoever and we will honor no claims for damages, regardless of
nature, for physical injury or property damage resulting from careless and/or irresponsible
handling, adjustments to equipment, improper operation, neglect, or abuse.
Gemtech reserves the right to make changes at any time and without notice, in prices, to
change specification or design, to add or remove accessory materials, and to add or delete
items without incurring any obligation.
Use of ammunition that does not meet SAAMI specifications will void all warranties.
REPAIRPOLICY
Gemtech maintains complete repair facilities for all suppressors manufac-
tured by them or their antecedent companies. Return authorization and shipping
instructions must be obtained prior to return. Contact Gemtech for this informa-
tion.
ATF no longer requires transfer on a Form 5 to the manufacturer for repair.
However, they do require a letter accompanying the weapon detailing the repairs
or modifications required. ATF requires proof of ownership, satisfied by a photo-
copy of the front of the owner’s Form 3, 4, or 5.
NOTE: ATF prohibits transferring the serial number to a new outer tube in the
case of damage to the tube. Tube damage will require a new suppressor.

SOUNDSUPPRESSORMODELPSR P. 9
Products, accessories, and copies of this
manual are available at our web store:
www.gem-tech.com

All Gemtech products are
100% manufactured in the
United States of America.