Umarex Defender CO2 BB Air Pistol: A Comprehensive Review

Introduction

The Umarex Defender CO2 BB Air Pistol is a high-quality, reliable air pistol that is perfect for target practice, plinking, and even small game hunting. This air pistol is powered by a 12-gram CO2 cartridge and can shoot BBs at a velocity of up to 410 feet per second. The Umarex Defender has an estimated price range of $60 to $80 and was launched in 2021.

Detailed Specifications

The Umarex Defender CO2 BB Air Pistol has several key features that make it a great choice for airgun enthusiasts. Here are some of its detailed specifications:

• Caliber: 0.177 inches (4.5 mm) 
• Velocity: Up to 410 feet per second 
• Action: Semi-automatic 
• Power source: 12-gram CO2 cartridge
• Capacity: 18 rounds 
• Barrel length: 4.5 inches 
• Overall length: 8.25 inches 
• Weight: 2.2 pounds 
• Sights: Fixed front and rear sights 
• Safety: Manual safety lever.

SAFETY INSTRUCTIONS

WARNING: THIS AIRGUN CAN CAUSE SERIOUS INJURY OR DEATH. READ AND FOLLOW THE INSTRUCTIONS CAREFULLY. DO NOT LOAD A PROJECTILE INTO THE AIRGUN UNTIL YOU ARE READY TO SHOOT. IF YOU DO LOAD A PRO-JECTILE AND THEN DECIDE NOT TO SHOOT, REMOVE IT EITHER MANUALLY OR BY SHOOTING THE AIRGUN AT A SAFE TARGET. AN UNLOADED AIRGUN WHICH IS “ON SAFE” IS SAFEST. ACCIDENTS HAPPEN FAST, PLEASE HANDLE THE AIRGUN SAFELY.

CAUTION: FAILURE TO FOLLOW THE INSTRUCTIONS AND RECOMMENDATIONS IN THIS OWNER'S MANUAL MAY RESULT IN BODILY INJURY INCLUDING FACE, EYE, AND EAR INJURY, BLINDNESS, OR DEAFNESS.

DESCRIPTION for Defender CO2 BB Air Pistol 

Learning the Parts of Your Air Pistol

OPERATION

WARNING: BE SURE THE AIRGUN IS ALWAYS POINTED IN A SAFE DIRECTION. NEVER POINT THE AIRGUN AT ANY PET OR PERSON EVEN IF IT IS UNLOADED. ALWAYS ASSUME AND HANDLE THE AIRGUN AS IF IT WERE LOADED AND READY TO FIRE.

CAUTION

• ONLY HANDLE THE AIRGUN WHEN IT IS ON SAFE.
• ALWAYS MAKE SURE THAT THE MUZZLE POINTS INTO A SAFE DIRECTION.

Operating the Safety

To Put the Defender “ON SAFE”

• Locate the safety on the right side of the air-gun above the trigger.
• Push in and forward (toward “S”)  (illustration 2A).

To Take the Defender “OFF SAFE”

• Locate the safety on the right side of the air-gun above the trigger.
• Push in and rearward (toward “F”) (illustration 2B).

CAUTION

• LIKE ALL MECHANICAL DEVICES, AN AIRGUN SAFETY CAN FAIL. EVEN WHEN THE SAFETY IS "ON SAFE", YOU SHOULD CONTINUE TO HANDLE THE AIRGUN SAFELY. NEVER POINT THE AIRGUN AT ANYTHING YOU DO NOT INTEND TO SHOOT.
• NEVER LOAD THE MAGAZINE UNTIL YOU HAVE VERIFIED THE AIRGUN WILL DISCHARGE CO2 PROPERLY.

Removing and Installing CO2 Capsule 

Installing a New CO2 Capsule

• Put the air-gun “ON SAFE”  (see Step 2).
• Check to make sure the built-in magazine is empty.
• Make sure a projectile is not loaded (see Step 4).
• If it contains CO2 (see Step 3B).
• Press the grip release button exposing the CO2 housing (illustration 3a).

• Before installing a 12g CO2 capsule, place one drop of RWS Chamber lube on the top of the small end of the 12g CO2 capsule.

  

• Insert the 12g CO2 capsule, with the small neck of the capsule pointing upward into the grip, and turn the piercing knob clockwise until it pierces the CO2 capsule.(illustration 3b)
• Push the pistol grip forward to close (illustration 3c).
• Make sure the capsule has been punctured. With the air-gun unloaded, pointed in a SAFE DIRECTION, take “OFF SAFE” (see Step 2B) and pull the trigger to fire. If it does not fire, tighten the piercing knob some more and repeat this step. 

NOTE: 

• A slight seepage of CO2 may occur until piercing screw is tight.
• Never try to force any CO2 capsule into or out of place. Do not store your air-gun with a CO2 capsule in it. If you know you will not be using your air-gun for an extended period of time, empty the CO2 capsule and remove it from the air-gun. (See Step 3B). This is very important to remember, as it will prolong the longevity of your air-gun seals.

WARNING: 

• USE ONLY 12g CO2 CAPSULES. ANY ATTEMPT TO USE OTHER TYPES OF GAS CAPSULES COULD BE EXTREMELY DANGEROUS AND COULD RESULT IN SERIOUS INJURY OR DEATH. GASES OTHER THAN CO2 COULD RESULT IN AN EXPLOSION OR RUPTURE OF THE AIRGUN.
• KEEP HANDS AND FACE AWAY FROM ESCAPING CO2 GAS.  IT CAN CAUSE FROSTBITE IF ALLOWED TO COME IN CONTACT WITH SKIN. ALWAYS MAKE SURE THE CO2 CAPSULE IS EMPTY BEFORE ATTEMPTING TO REMOVE IT FROM THE AIRGUN BY SLOWLY TURNING THE GAS CAPSULE PUNCTURE SCREW COUNTER-CLOCKWISE ALL THE WAY UNTIL YOU NO LONGER HEAR THE ESCAPE  OF CO2 GAS.

Removing a CO2 Capsule

• Put the air pistol “ON SAFE” (see Step 2).
• Check to make sure the built-in magazine is empty.
• Make sure the air-gun is unloaded (see Step 4).
• Point the air-gun in a SAFE DIRECTION.
• Put the air-gun “OFF SAFE” (see Step 2).
• Fire the air-gun until it will not fire, indicating the CO2 capsule is empty.
• Put the air-gun “ON SAFE”.
• Press the grip release button exposing the CO2 capsule.
• Use one hand to hold the air-gun at the top of the slide. Be sure to keep the muzzle pointed in a safe direction.
• Slowly turn the piercing knob counterclockwise (down) until it stops turning; allowing any remaining CO2 gas to escape.
• Remove the empty CO2 capsule and discard.
   

Loading and Unloading Projectiles

Loading Projectiles

• Put the air-gun “ON SAFE” (see Step 2).
• Always point the air-gun in a SAFE DIRECTION.
• Press the grip release button exposing the built-in magazine.
• Press the follower down and lock it to the left (illustration 4).
• Load up to 16 (.177 caliber) steel BBs through the loading port (illustration 4). 
  We recommend RWS Match-Grade BBs.
• Gently release the follower.
• Close the grip.

CAUTION: USE ONLY .177 CALIBER (4,5 MM) STEEL BBS. DO NOT ATTEMPT TO REUSE BBS THAT HAVE BEEN FIRED OR ARE DEFORMED. DO NOT USE BUCK SHOT, DARTS, BALL BEARINGS, OR OTHER FOREIGN OBJECTS BECAUSE THEY CAN CAUSE INJURY TO YOU OR SOMEONE ELSE OR MAY DAMAGE AND/OR JAM THE AIRGUN. 

WARNING: NEVER ASSUME THAT BECAUSE THE AIRGUN NO LONGER FIRES A PROJECTILE AND/OR THE MAGAZINE IS REMOVED FROM THE GRIP FRAME THAT A PROJECTILE IS NOT LODGED IN THE BARREL. ALWAYS TREAT THE AIRGUN AS THOUGH IT IS LOADED AND WITH THE SAME RESPECT YOU WOULD A FIREARM.

Unloading BBs

• Point the air-gun in a SAFE DIRECTION.
• Put the air-gun “ON SAFE” (see Step 2).
• Check to make sure the built-in magazine is empty.
• Point the air-gun in a SAFE DIRECTION.
• Put the air pistol “OFF SAFE” (see Step 2).
• Pull the trigger to fire until the air pistol no longer shoots projectiles.
• Put the air-gun “ON SAFE”.

NOTE: The air-gun must be charged with CO2 when following these steps but remember, do not store your air-gun with a CO2 capsule in it (See Step 3).
IMPORTANT: Firing the air-gun with too little gas pressure left may cause a BB to get stuck in the barrel.
NOTE: Many factors affect air-gun performance and velocity, including brand of projectile, lubrication, barrel condition and temperature.

Aiming and Firing Safely

• You and others with you should always wear shooting glasses to protect your eyes.
• Always aim your air pistol in a SAFE DIRECTION. When you are sure of your target and backstop, and the area around the target is clear, take “OFF SAFE” (See Step 2B) and squeeze the trigger to fire.
• Do not shoot at hard surfaces or the surface of water. Projectiles may bounce off or ricochet and hit someone or something you had not intended to hit.
• Do not shoot at fragile surfaces such as glass or mirrors.
• Always choose your target carefully. Only targets which cannot be completely penetrated or which will not cause ricochets should be used.
• Your backstop should be checked for wear before and after each use. Replace your backstop if the surface is worn or damaged, or if a ricochet occurs.
• The air pistol is correctly aimed when the front sight blade is positioned exactly in the notch and even with the rear sight. The top of the front sight blade should be even with the top of the notch in the rear sight. The bullseye should appear to rest on the top of the front sight (See illustration 5).

CAUTION: YOUR BACKSTOP SHOULD BE INSPECTED FOR WEAR BEFORE AND AFTER EACH USE. DISCONTINUE USE IF THE BACKSTOP SURFACE SHOWS SIGNS OF FAILURE. ALWAYS PLACE THE BACKSTOP IN A LOCATION THAT WILL BE SAFE SHOULD THE BACKSTOP FAIL. DISCONTINUE THE USE OF A BACKSTOP IF THE PROJECTILE REBOUNDS OR RICOCHETS. 

Use and Handling of CO2 Capsules

It is possible that certain conditions may affect a CO2 capsule, which can impact its proper performance. These conditions include the usage, maintenance and storage at temperatures that are higher or lower than normal outdoors temperatures (60º-80º F/16º-27º C). Another condition may be when the gun is fired rapidly.

1. High temperatures can increase pressure in the CO2 capsule and also within the gun, leading to higher than standard operating pressure. This excess pressure could cause the gun to malfunction or be permanently damaged. Maximum storage or operation temperature should never exceed 122°F (50°C). This temperature can be reached if you leave the gun under direct sunlight on a bright day. Thus, to ensure proper gun operation, do not expose it to high temperatures or direct sunlight for long periods of time. Otherwise, the CO2 capsule could overheat and explode, which could damage the airgun and cause injuries or death to people around it.
2. Fast consecutive shooting may produce a decrease of temperature in the gun, as well as the CO2 capsule. This could result in lower projectile velocities and may even lower gas pressure enough so that the pistol will not fire. This condition can be especially apparent when shooting in cold weather and can be avoided by allowing more time between shots. This permits the gas to increase in temperature and pressure and produce normal velocities.
3. During rapid fire, the muzzle velocity of each shot will diminish. This can affect shooting accuracy and you will get fewer shots per CO2 capsule.
4. Care should be exercised to insure that the gun is not shot with a CO2 capsule that is low in pressure. Here are some indicators of insufficient pressure:
   • The sound of the shot is not as loud as when the capsule is full.
   • The projectile hits the target, but in a lower position than it would with a full CO2 capsule (that is, the shooting speed has dropped).

CAUTION

• NEVER ATTEMPT TO REUSE A CO2 CAPSULE FOR ANY PURPOSE.
• ALWAYS CHECK TO MAKE SURE THE AIRGUN IS UNLOADED WHEN GETTING FROM STORAGE OR FROM ANOTHER PERSON.
• CO2 CAPSULES MAY EXPLODE AT TEMPERATURES ABOVE  122° F. DO NOT MUTILATE OR INCINERATE THEM. DO NOT EXPOSE THEM TO HEAT OR STORE CO2 CAPSULES AT TEMPERATURES ABOVE 122°F.

Maintaining Your Air-gun

With care and routine inspections your airgun will provide many sessions of shooting enjoyment. Abuse, neglect and continued exposure to the elements will impair the performance of any airgun. To ensure continued proper function, apply 1 to 2 drops of RWS Spring Cylinder oil onto all moving parts such as the BB follower, gas capsule piercing knob and the trigger hinge (1000 shots).

CAUTION  

• BEFORE ANY CARE, CLEANING OR MAINTENANCE, ALWAYS BE SURE YOUR AIRGUN IS UNLOADED. KEEP POINTED IN A SAFE DIRECTION. IT IS IMPORTANT TO PERFORM ROUTINE INSPECTIONS AND MAINTAIN YOUR AIRGUN PROPERLY.
• OILS THAT CONTAIN ACID OR RESIN CAN DAMAGE SEALS AND POSSIBLY THE FINISH OF THE AIRGUN.
• AN AIRGUN THAT IS NOT OPERATING PROPERLY MAY  BE DANGEROUS. IT SHOULD BE KEPT SAFELY FROM USE BY ANYONE UNTIL REPAIRED OR DESTROYED. DO NOT TRY TO TAKE THE AIRGUN APART. IT IS DIFFICULT TO REASSEMBLE AND IMPROPER DISASSEMBLY OR REASSEMBLY CAN CAUSE SERIOUS INJURY OR DEATH.

Trouble Shooting

Here are some common problems and solutions for the Umarex Defender CO2 BB Air Pistol: 

• Problem: The pistol is not firing. 
  Solution: Make sure that the CO2 cartridge is properly inserted and that the magazine is loaded with BBs. Also, ensure that the safety is off. 
• Problem: The pistol is leaking CO2. 
  Solution: Make sure that the CO2 cartridge is properly inserted and that the grip plug is securely tightened. If the leak persists, the cartridge may be faulty and should be replaced. 
• Problem: The pistol is not cycling properly. 
  Solution: Make sure that the magazine is properly inserted and that it is not overloaded with BBs. Also, ensure that the slide is fully cocked before firing.

Reviewing Safety

• Always aim in a SAFE DIRECTION. Always keep the muzzle of the air-gun pointed in a SAFE DIRECTION.
• Always keep your finger off the trigger and out of the trigger guard until ready to shoot.
• Never point the air-gun at anything you do not intend to shoot.
• Always treat the air-gun as though it is loaded and with the same respect you would a firearm.
• Never look down the barrel of an air-gun.
• Always keep the air-gun “ON SAFE” until you are ready to shoot.
• Always check to see if the air-gun is “ON SAFE” and unloaded when getting it from another person or from storage.
• Use only the proper size and type of projectile as it is marked on the air-gun.
• Never reuse ammunition.
• Do not shoot at hard surfaces or at the surface of water. The BB may bounce off or ricochet and hit someone or something you had not intended to hit.
• Do not shoot at fragile objects such as windows.
• Place the backstop in a location that will be safe should the backstop fail.
• Your backstop should be checked for wear before and after each use. All backstops are subject to wear and will eventually fail. Replace your backstop if the surface is worn or damaged or if a ricochet occurs.
• Do not attempt to disassemble or tamper with your air-gun. Unauthorized repairs or modifying the function of your air-gun in any way may be unsafe and will void your warranty.
• Before you store your air-gun, make sure it is unloaded, the CO2 capsule is removed, and is “ON SAFE.”
• Always store your air-gun in a secure location away from unauthorized users and separate from ammunition.

Warranty

Do not return defective or damaged product to the dealer. If your air-gun needs repair, call Umarex USA (479) 646-4210  and ask for the Service Department or visit www.umarexusa.com. DO NOT ATTEMPT TO DISASSEMBLE IT! Your air-gun requires special tools and fixtures to repair it. Any disassembly or modification not performed by Umarex USA will void the warranty.
WARNING: DO NOT BRANDISH OR DISPLAY THIS AIRGUN IN PUBLIC – IT MAY CONFUSE PEOPLE AND MAY BE A CRIME. POLICE AND OTHERS MAY THINK IT IS A FIREARM. DO NOT CHANGE THE COLORATION AND MARKINGS TO MAKE IT LOOK MORE LIKE A FIREARM. THAT IS DANGEROUS AND MAY BE A CRIME.

Setup Guide

Setting up the Umarex Defender CO2 BB Air Pistol is easy and straightforward. Here are the steps to follow: 1. Remove the magazine from the pistol and ensure that it is unloaded. 2. Insert a 12-gram CO2 cartridge into the pistol's grip by removing the grip plug and screwing the cartridge into place. 3. Load the magazine with BBs and insert it back into the pistol. 4. Cock the pistol by pulling back the slide. 5. Aim the pistol and squeeze the trigger to fire.

Pros & Cons

Pros

• Affordable price range 
• High velocity 
• Reliable and easy to use 
• Manual safety lever 
• Fixed sights for easy aiming

Cons

• May be too loud for some users 
• Not suitable for long-range shooting 
• May require frequent CO2 cartridge replacements