The CQB 5.56 SBR, and its pistol and rifle variants, the CQB 5.56 Pistol and Patrol 5.56, respectively, utilize only premium parts and accessories from the most reputable manufacturers, such as JP Enterprises, V Seven, and Geissele, to name a few. Proudly, the CQB 5.56 SBR boasts consistent sub-MOA groupings with factory loaded ammunition, sub–½ MOA with custom loads, even after the barrels reached over 725℉ from a full-auto torture test, and did not begin to fail until ~70,000 rounds were fired through the barrel.

 
 

Each firearm comes with the choice of not only M-LOK, Picatinny, or KeyMod handguards, but also the option of any of the below receivers. The face of our upper receivers are “squared” and barrels are bedded to ensure precise mating of barrel and receiver for added accuracy.

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  • Standard. Our upper and lower billet receivers are machined from 7075-T6 aircraft grade aluminum. The upper receiver contains M4 feed ramps and has a machined pocket to accommodate the Magpul BAD Lever. The lower receiver has a precision broached magazine well with beveled feed lips and engraved to be compatible with 45- and 60-degree short throw fire control selectors. A tension screw behind the grip screw is able to remove any “slop” between upper and lower. The trigger guard has an integrated large opening for gloved operations.

  • Forged Upper/Lower. Both upper and lower forged receivers are machined from 7075-T6 aircraft grade aluminum forgings. The upper receiver contains M4 feed ramps.

  • Slick Side. Both upper and lower receivers are the same as the Standard receivers but without the forward assist and ejector port cover.

  • Side-Charging. Lower is same as Standard. Upper is machined from 6061 billet aluminum and is the ONLY Non-Reciprocating Side Charger on the market to accept ANY standard MIL-SPEC BCG. Adjustable tension slide lock on charging handle. Rear dust cover trap door that seals shut when mated with lower.

  • Side-Folding Lower Receiver. The side folding lower receiver features all the great benefits of our traditional 7075-T6 billet lower receiver with the benefit of a folding stock. This option does require a proprietary recoil spring that will result in the elimination of the JP Enterprises Silent Captured Spring if this option is selected. Upper can either be Standard, Slick Side, or Side-Charging.

6061-T6 and 7075-T6 are two of the most common aluminum alloys around in AR-15 lower receiver use. While 6061 aluminum is a very useful and serviceable alloy, it is not as rugged as 7075-grade aluminum, especially when tempered to the “-T6” designation.

 

 

Detailed specifications

BARREL

If not the most important feature in a rifle, the barrel is one of the most important features. Our barrels are CHF 416 RS ordnance steel, LiFe QPQ nitrided, cryogenically treated, MPI inspected, and chambered in .223 Wylde with a 1:8 twist. The barrels also feature M4 barrel extensions to ensure the rounds are fed into the barrel more reliably, 1/2 x 28" muzzle thread, and 11-degree target crown.

The CHF (cold hammer forged) process uses repeated blows by a series of hammers to align the grain within the metal, causing more strength and rigidity and an overall more durable barrel. A 223 Wylde chamber has the same chamber angling as the standard 5.56 but with a .2240 freebore diameter, which results in a chamber that is sufficient to handle the hotter 5.56 load without concerns about pressure, and adds gilt-edge accuracy that is common in match-grade .223 barrels.

Traditional stainless steel barrels are highly accurate, but tend to wear out much faster than chromoly steels. Chromoly barrels last longer than stainless barrels, but do not have the accuracy. We do not feel there needs to be a compromise. By cold hammer forging 416 RS ordnance steel, applying ultra tough QPQ nitriding, and cryogenically treating the finished barrels, the life expectancy of these barrels far exceed the typical stainless barrels while still maintaining the accuracy found in match-grade .223 barrels.

To see how these barrels performed, a handful of random 10.3" (“Short”) and 16" (“Long”) barrels were sent away for independent testing. The results of the tests are below.

Teaser: The barrels consistently demonstrated sub-MOA groupings with factory loaded ammunition, sub-½ MOA in the 10.3" barrel with custom loads (even after the barrels reached over 725℉ from the full-auto torture test), and did not begin to fail until ~70,000 rounds were fired through the barrel.

Baseline Accuracy. Baseline accuracy was established on Lake City M193 NATO, Tula, Remington, and Winchester ammunition in 55-grain. Lake City M855 62-grain was also baselined. The results of these baselines are below:

 
 

Baseline accuracy with a variety of factory loaded ammunition.

 
 

Hot Barrel Accuracy. The NATO M193 55-grain ammunition was used for this test. After the baseline accuracy was established, each barrel was torture tested with seven 30-round mags in a full-auto configuration. Then the accuracy test was conducted again. During testing, the barrels were torture tested with seven 30-round mags in a full-auto configuration. The data from this test is below:

 
 

Average MOA after seven (7) 30-round mag dumps using NATO M193 55 grain.

 
 

Long-Term Throat and Barrel Erosion Testing. The 10.3" barrel underwent a baseline throat measurement of .224". This measurement was taken at the chamber end of the barrel, approximately .25" in from the beginning of the rifling. This article was then fired until projectiles began to keyhole. Keyholing is the phenomenon that occurs when the projectile is no longer being stabilized correctly and hits the target in an orientation other than point first. This occurred at ~70k rounds. The second throat measurement was taken in the same location as the baseline, and the measurement is .229", resulting in a delta of .005".

Accuracy Analysis. A 16" and a 10.3" barrel was each assembled into an upper receiver and mounted in a fixture that actuates the trigger through a solenoid, removing the human element from the equation. The accuracy baseline test was accomplished using MOA Custom loads (identified as “Long MOA” and “Short MOA” in the chart below). Each barrel then fired five (5) four-shot strings of each type of ammunition. These shots were fired into a target 215 feet (~72 yards, ~66 Meters) from the muzzle. This range was also indoors, removing environmental variables from skewing test data.

The test revealed the 10.3" barrel was more accurate while the 16" barrel provided superior velocity. All factory ammunition exhibited similar performance in the two barrel sizes—all factory ammunition resulted in sub-MOA accuracy. The data collected from the hot barrel test was quite interesting—both barrels held sub-MOA accuracy after heating to over 725℉ from the full-auto Hot Barrel Accuracy test. The 10.3" barrel opened up from 0.683 MOA to 0.784 while losing 35.15 feet per second of average velocity. The 16" barrel dissipated heat better and opened up from 0.699 MOA to 0.828 while losing 28.5 feet per second of average velocity.

Another surprising observation made during testing is how well these barrels shot the 62-grain M855 NATO round. The 1:8 twist of the barrels seem to stabilize the heavier projectile better than the 55-grain rounds tested. The average MOA chart is below:

 
 

Average MOA of 10.3" and 16" barrel with custom loads, factory loads, and with a hot barrel after seven (7) full-auto mag dumps of NATO M193 55 grain.

 
 

SOF Arms Velocity Testing. Using Federal XM193 5.56 55-grain NATO ammunition, the 10.3" barrel showed muzzle velocities averaging 2,828 ft/s. At 50 yards, the velocities averaged 2,621 ft/s. The 14.5" barrel showed muzzle velocities averaging 3,039 ft/s. At 50 yards, the velocities averaged 2,842 ft/s.

Headspace Check. Every barrel installed is headspace checked according to SAAMI’s specifications for maximum chamber dimensions using a JP Enterprises EnhancedBolt. At SOF Arms, we first utilize the “GO” gauge. If a rifle closes on a GO gauge, the chamber will accept ammunition that is made to SAAMI’s maximum specifications. Next, the “NO-GO” gauge is used to check the maximum headspace Forster recommends. This is NOT a SAAMI-maximum measurement. If a rifle closes on a NO-GO gauge, it may still be within SAAMI specifications or it may have excessive headspace. To determine if there is excessive headspace, the chamber is then checked with a FIELD gauge. The NO-GO gauge is a valuable tool to ensure a tight and accurate chamber. The “FIELD” gauge corresponds to the longest safe headspace. If a rifle closes on a FIELD gauge, its chamber is dangerously close to, or longer than, SAAMI’s specified maximum chamber size. Our FIELD gauges are slightly shorter than the SAAMI maximum in order to give a small safety margin.

UPPER PARTS

Muzzle Device. How can this rifle be “suppressor-optimized” if it does not come with a suppressor quick connect muzzle device? If all the suppressor manufacturers could get together and design a universal quick connect system with the ability to attach muzzle devices for unsuppressed operation, we would use it. The reality is the only universal attachment system is the 1/2" x 28" muzzle thread, which we do have. However, upon adding our firearms to your shopping cart, you can request specific muzzle devices be added at no additional charge.

For our 10.3" barrel, we utilize the JP Enterprises FH flash hider so you don’t piss off others while shooting a SBR. The FH beat out ALL other flash hiders in two different independent tests, turning in a lux result barely above ambient lighting.

 
 

Image shows the JP FH beating 28 other flash hiders during independent testing.

Image shows the JP FH beating 22 other flash hiders during independent testing.

 
 

For our 14.5" and 16" barrels, we include the Strike Industries J Comp Gen2 for both flash reduction and recoil compensation. A clone of the compensator found on the Type 89 assault rifle used by the Japanese military, the Strike Industries J Comp uses six ported side vents in a double chamber system to help redirect the gases released by a fired rifle. The front two ports of the J Comp minimize flash to help protect your night vision, ensuring you can land accurate follow-up shots in low light environments. We did test other compensators, such as the Precision Armament Hypertap, but the conclusiveness was too great to make shooting anything close to enjoyable.

Charging Handle. The Geissele Super Charging Handle (SCH) is 3D machined from a solid block of aircraft grade 7075-T6 aluminum. Its ambidextrous design allows for seamless operation from either side of the weapon. The levers are dual contoured similar to that of the charging handle of an M14, where not only the x-axis but also the y-axis receive radius cuts. The handling surface of the lever is also checkered, adding a textured grip aiding to the use when operating with gloves. The heightened rear lip of the SCH aids in mitigating gas blowback to the shooter when shooting with short barreled and suppressed weapon systems.

Handguard. All variants have the option of a M-LOK, Picatinny, or KeyMod free-float handguard. The M-LOK handguards have seven (7) sides M-LOK technology at the 3, 6, and 9 o’clock positions, as well as the upper and lower 45 quadrants, and a M1913 Picatinny rail at the top. The KeyMod handguards have seven (7) sides KeyMod technology at the 3, 6, and 9 o’clock positions, as well as the upper and lower 45 quadrants, and a M1913 Picatinny rail at the top. The Picatinny handguards have M1913 Picatinny rails at the top and 3, 6, and 9 o’clock positions, and diamond shaped heat vents. All handguards are made from 6061-T6 aluminum animate black hardcoat anodized to MIL-SPEC or better.

Unsure what to get? Go with M-LOK! After tests conducted by NSWC-Crane against other rail systems, the U.S. Special Operations Command went with M-LOK due to its superior performance. Repeated installation of the same rail in the same location experienced a point of aim shift of 1.3 MOA, which was less than other systems tested. Drop tests and load tests found M-LOK eventually failed but only at much higher loads than comparative rails.

We also include the Magpul AFG Angled Foregrip to assist with quick sight acquisition and reduce muzzle rise. The AFG’s ergonomic shape is designed to allow the shooter to have a firm hold of their weapon while firing and have an even distribution of weight pushing against the wrist and arm to allow better control of recoil and faster follow up shots. The AFG has horizontal grips to avoid sweat buildup and a low profile to keep it out of your hand’s way as much as possible. Best yet, you do not need retraining with this foregrip—can still rely on muscle memory and grip is as you would the handguard.

Dust Cover. The Strike Industries Ultimate Dust Cover was incorporated in this rifle due to its high-density polymer construction, making it more durable and functional than the traditional dust covers. The Ultimate Dust Cover features an adjustable detent set screw to allows operators to determine the how secure they want their dust cover to be. The dust cover is completely removable without having to remove the barrel nut or handguard.

LOWER PARTS

Lower Parts. The lower receiver incorporates MIL-SPEC precision machined lower parts but with an emphasis in four critical areas. First, stainless steel anti-walk pins for the hammer and trigger are included. Second, an ambidextrous safety selector that can be changed switched between a short throw 45-degree or a traditional 90-degree setting. Third, the Magpul B.A.D. Lever (Battery Assist Device) allows for quick reloading and malfunction clearance by extending a paddle to the right side of the weapon, allowing manipulation of the bolt stop from the fire control/ready position with the right-hand trigger finger (B.A.D. lever not available with side-charging receiver). Functional for also the “wrong-handed” shooter, the B.A.D. Lever also provides an oversized traditional bolt catch to assist in the fastest possible reloads with either thumb or palm engagement. Fourth, the trigger . . .

Trigger. The Elftmann ELF Tactical Service Trigger has been built for law enforcement and military duty. It is the only AR-15 trigger using aerospace grade sealed bearings, making for an incredibly smooth and fast trigger pull. Elftmann’s exclusive .043 double double wound polished piano wire hammer spring ensures full ignition of any ammo including .308 and 7.62x39. The entire travel distance was measured at 1.75 mm. The trigger pull ranges from 4 to 7 lbs. and is adjustable from the top just by opening the upper receiver and using a hex key. The amazingly short takeup, glass-rod crisp break and next to zero over-travel can be compared to the finest custom 1911 triggers. Below is a video showing the trigger pull, travel distance, and trigger reset.

Grip. The Magpul MIAD (MIssion ADaptable) GEN 1.1 Grip features removable and replaceable front and rear straps for a custom fit over multiple hand sizes and a removable inner core that holds an included 1/2 oz. reusable lubrication bottle. The inner grip can also hold a Gerber Short Stack weapons maintenance multi-tool and extra cores can be purchased to hold an extra bolt and firing pin, CR123A battery storage, or AA/AAA batteries.

STOCK ASSEMBLY

Stock. With the B5 Systems Enhanced SopMod Stock, which was the official pick of the U.S. military, you don’t have to worry about wobble, slippage, and improper cheek weld. Features a fixed sling mount and an overmolded steel anti-rotational QD mount. The B5 SopMod has two water-tight storage compartments for your front sight adjustment tool, extra batteries, carbon scraper, etc. In order to eliminate rattle of any items within these compartments, we suggest including earplugs in there as well.

For our pistol variants, we utilize the SB Tactical SBA4 pistol stabilizing brace, which features an integral, ambidextrous QD sling socket. No more pistol buffer tubes—this stock accepts MIL-SPEC carbine receiver extensions.

Click to enlarge

Buffer Tube. The 6-position AR-15 buffer tube is machined from 7075 T6 aluminum to MIL-SPEC dimensions with a Type III, Class II hard coat anodized finish. It also has over-the-breach drainage holes to allow water to be evacuated in submerged environments. The castle nut and QD end plate are machined from high carbon steel, heat treated for extra strength, and given a nitride finish for durability and corrosion resistance.

Buffer Spring. The JP Enterprises GEN 2 Silent Captured Spring (“SCS”) eliminates the ‘ting’ sound you hear in the buffer tube when firing suppressed. The SCS just doesn’t cure the annoying chintzy clang and springy sproing and rebarbative rattle that can be heard and felt both when manually cycling the charging handle and when firing—it smooths out the actual operation of the rifle as well. Gone is the vibration and spring binding that can be felt through the cheek, jaw, shoulder, hands, etc. The SCS minimizes bolt bounce, and can be tuned to suit a rifle’s specific operating system through different buffer weights (available for purchase separately at JP Enterprises) to allow for changes to the mass of the buffer and also offers five different spring weights (included) for selecting the perfect recoil spring power.

GAS SYSTEM

Adjustable Gas Block. We suspect if you are using this firearm for anything other than target practice, you need it to be accurate and reliable. We tested both piston systems and gas impingement systems. With our setup, we found the piston system to be unreliable for this build. The gas impingement (“GI”) system, however, exceeded our expectations.

Gas enters the chamber from two areas—the gas tube and the barrel when the bolt unlocks. The gas port size on a gas impingement system determines how much gas shoots down the gas tube and actuates the bolt carrier. When an AR is over gassed the bolt speed increases and this can cause rounds to not be picked up or the bolt not locking back on an empty magazine because the bolt is moving faster than the magazine can function to load an extra round or actuate the bolt catch. Both of these problems are problems with reliability.

Over gassed guns run much dirtier because of the extra pressures still in the barrel at the time the bolt unlocks. In a properly timed system, the bolt will unlock after the bullet exits the barrel and the barrel is relieved of all excess pressure. But when a suppressor is added to the equation, the path of least resistance for excess gas to escape to is the chamber when the bolt unlocks. Also, the additional gas being forced down the gas tube only adds to the large amount of crud in the upper receiver. All this extra crud causes reliability issues. This is why everyone says to run an AR wet—it is not because an AR needs the extra lubrication but because it helps suspend the crud and this helps the cruddy gun run. However, with an adjustable gas block set to the minimum gas impulse to run reliably, a properly gassed gun will shoot thousands of rounds between cleanings—and it will do so with a minimal amount of lubrication as well.

Having a properly gassed gun also reduces felt recoil. When a gun is over gassed the bolt unlocks earlier than is should when the pressures and gas volume are still higher than they should be. The additional pressures and volume exert more force upon the bolt and buffer. When this happens, it increases their speed as they travel rearward, and those fast-moving buffers and bolts come to an abrupt stop as they impact the rear of the buffer tube. This impact is felt as a strong jolt that most confuse with recoil. An AR should have the same or less felt recoil as a bolt action that weighs the same because the impulse is lengthened with the semi-automatic action.

Not all ammo is created equally. Some ammo has very low pressure and others are very hot (high pressure). Too low of pressure may cause failures to feed because of insufficient pressure to actuate the bolt carrier. Too much pressure may cause failures to feed because the bolt carrier is moving too fast. Thus, in order for the bolt carrier to actuate reliably across all pressures of ammo, the gas port needs to be large enough to accommodate the lowest pressure ammo and an adjustable gas block is required to restrict the amount of gas entering the gas tube when ammo is too hot. Below is a video on how to properly setup an adjustable gas block. Additionally, the adjustable gas block is useful in obtaining optimum port pressure on otherwise difficult-to-run setups such as suppressed weapons, short-barreled weapons or nonstandard cartridges.

Gas block is accessible through the side of the handguard for quick on-the-fly adjustments.

Gas blocks are generally made from carbon steel, stainless steel, or titanium. Carbon steel gas blocks are prone to rust and sensitive to some chemicals, which may erode the gas block over time. Titanium has as a thermal conductivity lower than most high performance steels and a thermal expansion coefficient nearly half that of steel. BUT, titanium also begins to loose strength at high temperatures faster than most high performance steels and is not recommended for use in applications at or above 660℉. At high temperatures the "super strong" nature of titanium quickly goes away making it equal or even inferior to much cheaper metals. Stainless steel has a small thermal expansion coefficient, is naturally corrosion and chemical resistant, and it is extremely hard, even compared with carbon steel. As a result of these considerations, we selected the JP Enterprises click-adjustable detent gas block, which is made from 416 stainless steel and consists of an easy-to-access side gas adjustment.

Enhanced Bolt Carrier. We selected the LANTAC Enhanced Bolt Carrier because of its unique shrouded and resized forward facing gas ports vent gas away from the operator’s face. This results in a system that runs flatter with a smoother energy pulse with a softer start to carrier movement. In addition the system also runs cooler and cleaner, there is also less pressurization of the upper receiver when running a suppressed barrel. The flared boss at the tail of the carrier enhances the BCG’s lock position within the upper and makes it more consistent, resulting in an accuracy improvement.

 
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Lantac_E-BCG1.png
 

Bolt. The original AR-15 designed by Jim Sullivan (not Eugene Stoner) was designed to work with ammunition having a chamber pressure of 50,000 pounds per square inch (psi), a 20-inch barrel and a rifle-length gas system. When the military resurrected the carbine program in 1985, they told Colt they wanted a 14½-inch barrel for use on the new carbine. However, this new carbine exceeded the design of the AR-15. The rifle Sullivan designed had 14,500 psi in the gas tube while the carbine-length system had 19,000 psi. Pressure inside the bolt carrier went from 1,500 to 2,500 psi. The significant boost in gas system pressure means that the bolt has to unlock with much more binding force on the lugs. Binding force is the friction between the bolt’s lugs and the lug abutments in the barrel extension. Too much binding force will cause bolt lugs to shear off. When an AR-15 experiences a catastrophic failure, it is almost always the bolt that breaks—it’s either a lug on either side of the extractor or the bolt body where the cam pin passes through it.

The MIL-SPEC alloy for a bolt is Carpenter 158 steel. To address the issues of increased pressure, our selected bolt, Sharps Xtreme Performance Bolt (Relia-Bolt) coated in DLC (Diamond Like Carbon), is machined from S7 tool steel and heat tempered, which results in a significantly increased strength when compared to Carpenter 158. S7 provides a 75% increase in tensile strength, and nearly 60% improvement in yield strength.

 
 

In extreme use conditions, a MIL-SPEC bolt may not fully lock due to fouling in the chamber or bolt/extension lugs. The Relia-Bolt answer to this problem is a self-lubricating and, for the most part, self-cleaning design. The DLC coating is self-lubricating and it’s essentially self-cleaning—it can literally be cleaned by wiping with a soft cloth. The tapered leading edges of the bolt lugs, in theory, also help to plow through buildup around the barrel extension lugs which could occur during extreme neglectful maintenance or situations where a high amount of debris may have found their way into the chamber area.

In a normal working state, the bolt is held in an unlocked position for the length of the cycle by the upper receiver capturing the cam pin so the bolt cannot accidentally lock mid-cycle or as it picks up another round. There is a notch in the upper receiver which is “timed” to allow the cam pin to rotate to a locked position after the bolt lugs have passed and entered the barrel extension lugs. However, a severely worn upper or cam pin can create a situation where the bolt can partially start its counter-clockwise locking cycle just from the pressure of picking up a round or a sticky round in the magazine. When this happens, the clocking/timing is off on the bolt, and the lugs on the bolt and barrel extension collide versus interlocking, thus preventing lockup. The Sharps solution is to round/taper both the front leading edges and the left counter-clockwise facing edges of the lugs. This directional wedge effect drives through chamber buildup and will drive the bolt face back, clockwise, slightly back to an unlocked position to engage the barrel extensions without jamming. Once into battery, the rear edges of the lugs fully engage the barrel extension for absolute strength and security.

Click on image to enlarge

We did simulate the jam the Relia-Bolt was designed to prevent. We pulled the cam pin out of a carrier and simulated the overclocking issue and the Relia-Bolt clocked back into position where the standard bolt jammed. In short, things would have to be going horribly wrong with a severe amount of wear on the receiver cam pin channel and/or the cam pin itself for the lug tapers Sharps Relia-Bolt to be used. In an extreme environment or a long-term fielded carbine, fouling could create a bolt jam in traditional MIL-SPEC bolt designs. But bolt breakage is far more likely to occur in MIL-SPEC bolts. Sharps’ Relia-Bolt addresses both issues with the stronger S7 tool steel and proprietary rounded/tapered lugs that push past carbon and debris when the square edges of traditional bolts would typically jam.

We took it a step further and made the Relia-Bolt more reliable by replacing the MIL-SPEC ejector springs with a heavy coil design that increases the extractor tension. Our extractor spring is made of chrome silicon and is heat treated, stress relieved, and shot peened for added durability.

Gas Tube. The “weak link” in gas impingement guns is the gas tube—it is usually the first to fail because it’s unable to withstand the hot gases transferred through it (see video below). Some call this a fail-safe measure, arguing the gas blocks are designed to fail before any other part of the rifle fails. We consider it a liability. Our gas tubes are constructed with heat-treated Inconel to withstand the high temperatures encountered during rapid firing. This gas tube eliminates the weak link in impingement systems.

MAGAZINES

Some things should never be plastic. For this reason, we selected C Products Defense’s DURAMAG Speed magazines to be included with our firearms. DURAMAG Speed bodies are constructed of 6061-T6 aluminum and are Type III, Class 2 hard-coat anodized, unlike other magazines that use inferior coatings to color their aluminum USGI-style magazines. This battle-proven magazine is lightweight, durable and feeds every time. DURAMAG Speed mags have been the magazine of choice for OEM, Law Enforcement and Military Units throughout the world and are safe for extended storage while loaded. DURAMAG provides further protection by using a proprietary coating (T-360), which bonds at the molecular level and will never wear off. The T-360 coating process also decreases friction and increases lubricity inside and out. The result is that even when using the dirtiest ammunition, DURAMAG magazines will effectively resist dirt or dust accumulation, allowing flawless operation and reliability.

The weakest link in polymer magazines is one invisible to the naked eye. Polymer magazines have a strong affinity to attract moisture and will absorb it into their molecular structure when exposed to ambient air. This moisture within the polymer reacts constantly with surrounding environmental factors. The vapor pressure within the polymer increases to equal the vapor pressure of the surrounding environment until equilibrium occurs. This is referred to as polymer moisture equilibrium or PME.

When an environment of hot and dry air surrounds a wet hygroscopic polymer element, the vapor within polymer exits to the atmosphere, drying out the polymer. In other words, the polymer becomes dry and will deform from its original design and lose its flexibility. The opposite is also true, when the moisture within the polymer is cooled near or below the freezing point, the moisture within the polymer will freeze and the polymer will crack. There have been countless reports of polymer magazines shattering when dropped on a hard surface. Aluminum and stainless steel, however, do not have an affinity for moisture. Any moisture gained through condensation or immersion remains on the surface and is easily removed via evaporation or simply wiping it off. No moisture is absorbed into the metal.

All SOF Arms firearms comes with two (2) magazines.

LUBRICATION

Know of any other manufacturer that discusses the lubrication they use on their firearms? MIL-COMM is the only brand that supplies extreme performance weaponry lubricants to all branches of the U.S. Military, including U.S. Special Forces, or to more than 20 U.S. allies militaries worldwide, or to nearly all leading Federal, State, and local law enforcement agencies. MIL-COMM’s world renowned TW25B offers all of the below features and benefits:

  • Optimizes performance by providing long-lasting lubrication and corrosion protection.

  • Performs dependably in all climates, under all weather conditions.

  • Greatly reduces friction and wear; extends the life of parts.

  • Proven superior in sand, salt water, and humidity.

  • Repels sand, dust, grit, dirt and debris.

  • Resists wash-off, wear off, burn-off and evaporation.

  • Reduces time and frequency of maintenance events.

  • No known shelf-life.

Will all of these powerful characteristics, it would be wrong for us to not use TW25B.

Due to part availability, specifications are subject to change without notice. In the event a part becomes unavailable, SOF Arms maintains the right to determine which replacement part of equal or greater value will be used.