Cry Havoc Takedown Kit QRB Quick Detach Barrel

Cry Havoc Takedown Kit QRB Quick Detach Barrel

Cry Havoc 308 AR Upper Receiver Takedown Kit
Cry Havoc QRB 308 AR Upper Receiver Takedown Kit

Cry Havoc Takedown Kit (QRB Barrel Kit)

Cry Havoc Tactical takes their QRB (Quick Release Barrel) Upper Receiver Takedown Kit and scales it up for the big guns!
Designed for your AR 308 or 6.5 Creedmoor the QRB allows you to quickly detach the barrel giving you the ability to store or carry your rifle in a much-reduced profile and then when needed quickly reassemble the rifle while holding within 1 MOA.

Each Cry Havoc Takedown Kit contains complete instructions and all parts to convert your rifle or without drilling or any permanent modifications. Although they recommend installation be done by a Gunsmith, if you can install a barrel on an upper receiver, you can install this kit. Simple hand tools, an Armour’s wrench, and receiver block/vise are all that are needed. Returning your rifle or pistol back to stock is as easy as the installation.

The QRB main body is Hard Anodized Aluminum and the Stainless-Steel hooks, levers, star nut, and gas extension are finished in Black Nitride for maximum durability.

Available from Brownells

Once the QRB Kit is installed, it is amazingly quick to assemble your rifle or pistol without the worry of damaging your gas tube. The operator would simply lock the bolt back, insert the barrel extension into the receiver, rotate the barrel until the alignment pin enters the alignment hole, and then seat the barrel in place. Next, hook the two clips on the receiver plate and engage the levers to the closed position, never taking your hand off the pistol grip. Nothing to depress! Just drop the bolt and you are ready to fire… All in less than 6 seconds!

To remove the barrel assembly for storage, first, remove the magazine, lock the bolt back, check for an empty chamber, pull levers away from the handguard, remove hooks from the receiver plate and pull the barrel away from the receiver. Just that simple. No barrel rattling around in the handguard or gloves needed! Make sure to check out the videos in the Media Tab to see these steps happen in real-time. You will be amazed.

  •  The QRB Kit is only compatible with Free Float Hand Guards 2.2″ wide or less and will add 1.7″ to the length of the Hand Guard.
  • Purchase the correct kit by selecting the proper length gas tube to your barrels gas system length.

Cry Havoc Takedown Kit 308 QRB (308 AR Upper Receiver Takedown Kit)

From Cry Havoc Tactical

Our Cry Havoc Takedown Kit currently in use by the United States Air Force, utilizing the GAU-5A Aircrew Self Defense Weapon is the most compact and effective survival rifle for a downed Pilot. Used in the ACES II Ejection Seat Survival Kit, the GAU-5A has four magazines totaling 120 rounds, allowing a downed pilot enhanced protection. A QRB Kit-equipped AR-15 Carbine or Pistol gives you the smallest possible package with NO drilling or modifications to your existing AR Platforms! Easy ONE HAND operation. You want compact – You got it!

Now you can have The Ultimate Take Down Rifle! Our Patented 308 QRB System is designed to work on YOUR gas impingement DPMS/SR25 style rifle with a Free Float Hand Guard system 2.2″ wide or less and will add 1.7″ to the length of the Hand Guard. Now the Rifle System can break down to just the length of the barrel, meaning a 16″ 308 Carbine becomes two pieces under 17″ total, WITHOUT the worry of a full-size gas tube protruding beyond the barrel end, just waiting to be damaged!

Other possibilities available are the ability to do a 12.5″ pistol with a LAW Tactical folding “stabilizer” and have a 13″ 308 Package Pistol capable of firing 150-grain bullets at 2450 fps. Hard to match that with a 300 Blackout firing a 150 grain out a 16″+ barrel. This IS compact firepower!!! Watch your eyebrows! The United States Patent # 6829855

Now for your 308 or 6.5 Creedmoor. Have your large caliber with you at all times. The “Big Boy” QRB allows you to remove the barrel of your DPMS/SR25 Style rifle or pistol quickly. NO drilling or modifications needed!

  • Able to take along your AR308 style rifle in a small package.
  • Assemble converted rifle in seconds, even in total darkness.
  • Easily convert to multiple calibers – like 308 NATO to 6.5 Creedmoor.
  • Holds within 1 MOA of original rifle.
  • Easy install; Can be done without special tools if on a new install. No permanent modifications.
  • Proudly made in the USA – that means something to us.

Includes Barrel Plate, Receiver Plate, Gas Extension, and Gas Tube.

The 308 QRB Kit can only be used on Barrels with a maximum outside diameter of 1.200″ and Free Float Hand Guards with a maximum width of 2.2″ Also the QRB will add 1.5″ to the length of your free-floating handguard.

BSF BARRELS 6.5 CREEDMOOR RIFLE+2 GAS 1-8 TWIST 22 INCH FLUTED

BSF BARRELS 6.5 CREEDMOOR RIFLE+2 GAS 1-8 TWIST 22 INCH FLUTED

Picture of a BSF BARRELS 6.5 CREEDMOOR RIFLE+2 GAS 1/8 TWIST 22" BLACK/GRAY FLUTED

BSF Barrels 6.5 Creedmoor Rifle +2 Gas 1/8 Twist - 22" Black/Gray Fluted

After turning down the barrel, BSF Barrels jacket a 416R Stainless steel match barrel in a roll-wrapped carbon fiber sleeve and load it under tension.  BSF Barrels use this jacketing method rather than wrapping the barrel in carbon fiber because this method of wrapping has been proven to trap heat and cause delamination.

 The carbon fiber used is specially designed to move at the same expansion rate as 416R stainless steel. BSF Barrels drill holes into the carbon fiber allowing air to move around the barrel and vent heat quicker without any delamination issues.  Using the Carbon Fiber this way keeps the rifling straighter the warmer the barrel gets because it’s under tension. This allows us to maintain superior stiffness and strength while keeping the barrel extremely lightweight.

BSF Barrels 6.5 Creedmoor Rifle Barrel Specifications:

  • 6 Groove Button Rifling
  • Thread: 5/8″ 24
  • .875 OD
  • Chambered in 6.5 Creedmoor
  • 22″ Rifle+2 Gas
  • Weight 34.7 oz
  • Twist Rate 1:8
  • PATENT PENDING

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Lilja 6.5 Creedmoor Drop In AR308 Barrels

Lilja 6.5 Creedmoor Drop In AR308 Barrels

Picture of a Lilja 6.5 Creedmoor Drop In AR308 Barrel

Lilja 6.5 Creedmoor Drop In AR308 Barrels

When it comes to rifle barrels they can often be separated into different classes of performance. The top level performers are what I refer to as “No Excuses Barrels”. Lilja is one of the small handful of custom barrel manufactures producing these no excuses barrels for winning competitive shooters world wide. More importantly Lilja Rifle Barrels was named exclusive supplier for .30 caliber Mk13, Mod 7, and .50 caliber Mk15 barrels for the Navy SEALS. Lilja is now offering benchrest level performance 6.5 Creedmoor drop in barrels for 308 AR/AR308 shooters. They are available in 20″, 24″ fluted and unfluted.

We are offering an AR type barrel chambered for the 6.5 Creedmoor cartridges. These are available in four styles and all are completely finished drop-in type barrels. They are finish-chambered and have a DPMS style barrel extension installed and the gas port hole drilled for a rifle-length gas system. They also are threaded 5/8″ – 24 at the muzzle. These barrels are not compatible with the Armalite or Rock River Arms rifles.

All versions of this stainless steel AR-type barrel are chambered with a PTG semi-auto match reamer. These barrels are rifled with our 8″ twist 3-groove. These barrels are also hand-lapped to our internal finish standards. The section forward of the gas block section is engraved: “Lilja AR 6.5 Creedmoor” The barrel extensions are a DPMS type and these barrels will headspace properly with DPMS type bolts. The gas block and gas port holes are positioned for standard rifle length gas tubes.

Lilja Barrels 6.5 Creedmoor AR308 Drop In Barrel Specifications

Lilja 6.5 Creedmoor AR1024 Specifications:

The overall length is 24″. Gas block size is .936″. The diameter in front of the barrel extension is 1.200, then .975″ diameter to the gas block and then .875″ diameter from the gas block to the muzzle. The unfluted barrel is 4.25 pounds and the fluted version is 3.90 pounds. Muzzle threads are 5/8″ – 24.

Lilja 6.5 Creedmoor AR10740 Specifications:

The shorter barrel in the image is our AR10740 contour, very similar to our .223 AR740 contour in our .223 barrels. Gas block size is .750″. The diameter in front of the barrel extension is 1.200″ and then the profile drops down to .750″ and then up to a shoulder for the .750″ diameter gas block section and then down to .740″ to the muzzle. Muzzle threads are 5/8 – 24.

Weight is 2.5 pounds, and the unfluted is 2.7 pounds.

6.5 Creedmoor AR Barrels | Drop-In AR308 Barrels

6.5 Creedmoor AR Barrels | Drop-In AR308 Barrels

6.5 Creedmoor AR Barrels

Converting your large frame AR to shoot 6.5 Creedmoor is a simple barrel change. Whether replacing a .308 barrel or building a 6.5 Creedmoor AR from parts it is advisable to use a new bolt and of course verify proper headspace. Never use a bolt on different barrels. Many barrel manufacturers can provide a matching bolt.

It’s important to note that 6.5 Creedmoor is a relative new comer on the AR scene. A good knowledge of firearm function is imperative. Some builds and upgrades might require tweaking of the gun to function consistently and accurately. We recommend using and adjustable gas block when possible.

Picture of a Criterion Barrels 6.5 Creedmoor Hybrid Contour Barrel

Criterion Barrels 6.5 Creedmoor Hybrid Contour Barrels

Criterion Hybrid contour match grade 6.5 Creedmoor AR barrels offer an ideal configuration for those seeking extreme accuracy without the added weight of a heavy barrel contour.

Featuring a flatter trajectory and higher ballistic coefficient than the traditional .308 Winchester alternative, the 6.5 Creedmoor has grown in popularity with many long range shooters.

Designed to be compatible with DPMS, Midwest Industries, Remington, and Fulton Armory pattern rifles, these 6.5 Creedmoor barrels can be directly swapped with factory .308 barrels. Button rifled and hand lapped to ensure consistent bore uniformity, Criterion 6.5 Creedmoor AR barrels incorporate a 5/8 x 24 muzzle thread and finished chamber.

Headspace should be checked prior to installation by a qualified gunsmith. NOTE: The 18″ barrel utilizes a .750″ gas block while the 22″  utilizes a .875″ gas block (NOT included for either).

Picture of a Fulton Armory 6.5 Creedmoor AR Barrel

Fulton Armory 6.5 Creedmoor AR Barrel, 24"

Fulton Armory 6.5 Creedmoor AR Barrel, 24″, Bull, 1×8, Stainless, by Criterion Barrels. For use on DPMS/Remington/FA pattern .308 AR rifles with a rifle-length gas system, includes barrel extension.

Uniformity of the bore dimension, groove dimension, and twist, along with the finish produced by hand lapping are essential for the ultimate accuracy of the barrel which achieves “Match Quality”. Chambered in 6.5 Creedmoor (NOT .308 Win)
Specifications
  • 24″
  • Bull contour, 4.79 lbs
  • 1-8 twist 6 Groove
  • .936 Gas Block
  • 5/8×24 Threaded or Plain muzzle (.875)
  • 6.5 Creedmoor finished chamber
  • Rifle-length gas system
  • Gun barrel quality 410 stainless steel
  • Stainless steel, in the white (Target Gray matte finish available)
  • Button rifling, double stress relieved
picture of a JP Rifles 6.5 Creedmoor AR Barrel 22"

JP Rifles 6.5 Creedmoor AR Barrel 22"

Manufactured to our exacting specifications and used in all of our rifles, JP Supermatch™ barrels are turned from 416R stainless steel, lead lapped, air-gauged and cryogenically treated for cold bore shot predictability, minimum thermal drift, outstanding accuracy and extended barrel life. This barrel also includes a JP High Pressure Enhanced Bolt individually head-spaced to the barrel for flawless fit and function.

JP Rifles 6.5 Creedmoor AR Barrel 22″ JPSM6.5C-22M8XL Specifications

Chamber: 6.5 Creedmoor, Length: 22″, Gas System: Extra long, Twist: 1:8 button rifled, Contour: .750 under hand guard/.875 in front of gas, Diameter at Gas Block: .936, Muzzle Threads: 5/8-24 TPI, Material: 416R Stainless.

JP Rifles parts are designed to be used as a system and not stand alone to be mixed with other manufacturers parts. if you make the decision to go with the JP 6.5 Creedmoor barrel also use their recoil and gas system parts. You will be pleasantly rewarded with great accuracy and reliability.

Picture of a Ballistic Advantage 6.5 Creedmoor AR Barrel

Ballistic Advantage 6.5 Creedmoor AR Barrels

This 6.5 Creedmoor chambered (DPMS style) Ballistic Advantage barrels are machined from 416R Stainless Steel with a bead blasted finish. Our Premium Series 6.5 Creedmoor Barrels are proof fired and MPI tested, ensuring the best in quality and accuracy.

6.5 Creedmoor is the perfect option if you’re looking to maximize the accuracy of your .308 platform. Apart from a simple barrel swap, all parts, including the bolt and mag, remain the same as a normal .308 build. The inherently accurate 6.5mm projectile, the increasing amount of off-the-shelf match grade factory 6.5 Creedmoor ammunition, and the extremely soft recoil pulse all combine to create one of the best black rifle options available.

Picture of a Christensen Arms 6.5 Creedmoor Carbon Fiber 308 AR Barrel

Christensen Arms 6.5 Creedmoor Carbon Fiber 308 AR Barrels

Christensen Arms 6.5 Creedmoor Carbon Fiber 308 AR Barrels are well regarded for making excellent carbon fiber wrapped barrels. In the 6.5 Creedmoor chambering the AR .308 barrels are available in 16″ and 20″ lengths with mid-length gas systems.

Designed using precision engineering adopted from the aerospace industry, Christensen Arms 6.5 Creedmoor Carbon Fiber 308 AR Barrels are crafted using a proprietary layered design that offers any marksman superior accuracy and performance. The barrel lining is made from match-grade 416R stainless steel and is measured to a tolerance of +/- .0001. When it comes to accuracy, Christensen Arms carbon-fiber barrels have performance you can trust. Includes gas block and gas tube.

Specs: Christensen Arms 416R Stainless Steel Aero grade Carbon Fiber Wrapped, Match Chamber, Button Rifled, ⅝ × 24 Threaded Muzzle

Picture of a PROOF RESEARCH 308 AR PR-10 BARREL 6.5 CREEDMOOR CAMGAS GAS SYSTEM

PROOF RESEARCH 308 AR PR-10 BARREL 6.5 CREEDMOOR CAMGAS GAS SYSTEM

Add Proof Research to the list of 308AR barrel and rifle manufacturers to implement a non standard gas length on their 6.5 creedmoor barrels. Some companies refer to this new length as +2 (plus 2 inches). Proof Research designates their new gas length as “CAMGAS”. Moving the gas ports 2 inches closer to the muzzle adds a bit of dwell to the pressure curve. Basically it tames the action resulting smoother cycling and function. Check availability.

Proof research recommends the JP high pressure bolt. JP uses the high pressure bolt in their +2 rifles. Obviously a +2 gas tube is also required.

PROOF RESEARCH 308 AR PR-10 BARREL 6.5 CREEDMOOR CAMGAS GAS SYSTEM SS

The PROOF Research AR 308 PR-10 barrel provides owners of AR-10-pattern rifles with a 6.5 Creedmoor-chambered rifle that includes a number of enhanced features over traditional barrel styles. These long range specific barrels provide the ultimate in accuracy and will maintain their performance in the harshest of conditions.

The PROOF Research AR 308 PR-10 barrel uses the company’s innovative CamGas system, which works to reduce the speed of the bolt carrier and improve overall function and reliability of 6.5 Creedmoor semi-auto rifles.

Provide shooters with enhanced accuracy on par with match-grade guns
Better cooling properties provide improved barrel life
POI shift does not occur during extended fire strings
The proprietary gas tube is included, but requires use of a JP enhanced high pressure bolt for best function. (452-000-113)

The PROOF Research AR 308 PR-10 barrel is cut rifled from double stressed relived 416R stainless steel and features a threaded muzzle with a 5/8×24 TPI thread pitch for the addition of muzzle accessories.

PROOF RESEARCH CAMGAS GAS SYSTEM

With the release of its new patent-pending Caliber Matched Gas System (CAMGAS) barrels, PROOF Research has eliminated the issues traditionally associated with building 6.5mm and .260 rifles on 308 AR AR-10 platforms. Until now, AR-variant shooters looking for ballistic advantages from either of these calibers were faced with excessive bore pressures that necessitated makeshift solutions such as clipping buffer springs, adjusting buffer weights, and/or relying on adjustable gas blocks, to keep their rifles functioning properly.

PROOF’s R&D team has solved the overpressure issue with gas systems tuned specifically to the cartridge/barrel-length combination. “By moving the gas port, the pressure in the bore is given time to reduce to that comparable of a .308 Winchester with a rifle-length gas system, which is what the 308 AR AR-10 system was designed around,” said Greg Hamilton, PROOF’s research-and-development weapons specialist who’s also a 3-Gun and PRS competitive shooter. “The recoil impulse is noticeably smoother, which helps keep you on target while taking advantage of a more efficient projectile. Case extraction is also easier, with less case-head smearing, so the brass is in much better condition for reloading.”

In recent years, 6.5mm Creedmoor and .260 Remington have become increasingly popular in long-range shooting competitions. The .260 in particular represents an outstanding caliber for a military counter-sniper role—out to roughly 1,000 meters—in smaller- to mid-sized weapon systems. It offers exceptional accuracy and superior ballistics over the ubiquitous .308 while dishing out substantially less recoil and enough energy to make it a legitimate contender for military and law enforcement applications.

“I’ve been using prototype CAMGAS barrels, in both .260 and 6.5 Creedmoor, in competition for almost a year with excellent results,” Hamilton explained. “Both rifles ran flawlessly through high-round, fast-cadence stages, firing hundreds of rounds with 100 percent reliability and zero maintenance or cleaning. From recoil to reliability, every aspect of performance was improved compared to the typical un-tuned barrel.”

PROOF Research currently offers Caliber Matched Gas System barrels chambered for 6.5mm Creedmoor and .260 Remington in three separate lengths: 20, 22, and 24 inches. Every CAMGAS barrel comes standard with an easy to install custom-length gas tube.

Visit Proof Research

Picture of a Lilja 6.5 Creedmoor Drop In AR308 Barrel

Lilja 6.5 Creedmoor Drop In AR308 Barrels

We are offering an AR type barrel chambered for the 6.5 Creedmoor cartridges. These are available in four styles and all are completely finished drop-in type barrels. They are finish-chambered and have a DPMS-style barrel extension installed and the gas port hole drilled for a rifle-length gas system. They also are threaded 5/8″ – 24 at the muzzle. These barrels are not compatible with the Armalite or Rock River Arms rifles.

All versions of this stainless steel AR-type barrel are chambered with a PTG semi-auto match reamer. These barrels are rifled with our 8″ twist 3-groove. These barrels are also hand-lapped to our internal finish standards. The section forward of the gas block section is engraved: “Lilja AR 6.5 Creedmoor” The barrel extensions are a DPMS type and these barrels will headspace properly with DPMS type bolts. The gas block and gas port holes are positioned for standard rifle length gas tubes.

 

Lilja Barrels 6.5 Creedmoor AR308 Drop In Barrel Specifications

Lilja 6.5 Creedmoor AR1024 Specifications:

The overall length is 24″. Gas block size is .936″. The diameter in front of the barrel extension is 1.200, then .975″ diameter to the gas block and then .875″ diameter from the gas block to the muzzle. The unfluted barrel is 4.25 pounds and the fluted version is 3.90 pounds. Muzzle threads are 5/8″ – 24.

Lilja 6.5 Creedmoor AR10740 Specifications:

The shorter barrel in the image is our AR10740 contour, very similar to our .223 AR740 contour in our .223 barrels. Gas block size is .750″. The diameter in front of the barrel extension is 1.200″ and then the profile drops down to .750″ and then up to a shoulder for the .750″ diameter gas block section and then down to .740″ to the muzzle. Muzzle threads are 5/8 – 24.

Weight is 2.5 pounds, and the unfluted is 2.7 pounds.

308AR AR-10 Bolt Carrier Group Link
308AR AR-10 Scope Link
308AR AR-10 Trigger Link
308AR AR-10 Technical Link

PROOF RESEARCH 308 AR PR-10 BARREL 6.5 CREEDMOOR CAMGAS GAS SYSTEM SS

PROOF RESEARCH 308 AR PR-10 BARREL 6.5 CREEDMOOR CAMGAS GAS SYSTEM SS

PROOF RESEARCH 308 AR PR-10 BARREL 6.5 CREEDMOOR CAMGAS GAS SYSTEM
PROOF RESEARCH 308 AR PR-10 BARREL 6.5 CREEDMOOR CAMGAS GAS SYSTEM 2

PROOF RESEARCH CAMGAS GAS SYSTEM

Add Proof Research to the list of 308AR barrel and rifle manufacturers to implement a non standard gas length on their 6.5 creedmoor barrels. Some companies refer to this new length as +2 (plus 2 inches). Proof Research designates their new gas length as “CAMGAS”. Moving the gas ports 2 inches closer to the muzzle adds a bit of dwell to the pressure curve. Basically it tames the action resulting smoother cycling and function. Check availability.

Proof research recommends the JP high pressure bolt. JP uses the high pressure bolt in their +2 rifles. Obviously a +2 gas tube is also required.

PROOF RESEARCH 308 AR PR-10 BARREL 6.5 CREEDMOOR CAMGAS GAS SYSTEM SS

The PROOF Research AR 308 PR-10 barrel provides owners of AR-10-pattern rifles with a 6.5 Creedmoor-chambered rifle that includes a number of enhanced features over traditional barrel styles. These long range specific barrels provide the ultimate in accuracy and will maintain their performance in the harshest of conditions.

The PROOF Research AR 308 PR-10 barrel  uses the company’s innovative CamGas system, which works to reduce the speed of the bolt carrier and improve overall function and reliability of 6.5 Creedmoor semi-auto rifles.

  • Provide shooters with enhanced accuracy on par with match-grade guns
  • Better cooling properties provide improved barrel life
  • POI shift does not occur during extended fire strings
  • The proprietary gas tube is included, but requires use of a JP enhanced high pressure bolt for best function. (452-000-113)

The PROOF Research AR 308 PR-10 barrel is cut rifled from double stressed relived 416R stainless steel and features a threaded muzzle with a 5/8×24 TPI thread pitch for the addition of muzzle accessories.

PROOF RESEARCH CAMGAS GAS SYSTEM

With the release of its new patent-pending Caliber Matched Gas System (CAMGAS) barrels, PROOF Research has eliminated the issues traditionally associated with building 6.5mm and .260 rifles on 308 AR AR-10 platforms. Until now, AR-variant shooters looking for ballistic advantages from either of these calibers were faced with excessive bore pressures that necessitated makeshift solutions such as clipping buffer springs, adjusting buffer weights, and/or relying on adjustable gas blocks, to keep their rifles functioning properly.

PROOF’s R&D team has solved the overpressure issue with gas systems tuned specifically to the cartridge/barrel-length combination. “By moving the gas port, the pressure in the bore is given time to reduce to that comparable of a .308 Winchester with a rifle-length gas system, which is what the 308 AR AR-10 system was designed around,” said Greg Hamilton, PROOF’s research-and-development weapons specialist who’s also a 3-Gun and PRS competitive shooter. “The recoil impulse is noticeably smoother, which helps keep you on target while taking advantage of a more efficient projectile. Case extraction is also easier, with less case-head smearing, so the brass is in much better condition for reloading.”

In recent years, 6.5mm Creedmoor and .260 Remington have become increasingly popular in long-range shooting competitions. The .260 in particular represents an outstanding caliber for a military counter-sniper role—out to roughly 1,000 meters—in smaller- to mid-sized weapon systems. It offers exceptional accuracy and superior ballistics over the ubiquitous .308 while dishing out substantially less recoil and enough energy to make it a legitimate contender for military and law enforcement applications.

“I’ve been using prototype CAMGAS barrels, in both .260 and 6.5 Creedmoor, in competition for almost a year with excellent results,” Hamilton explained. “Both rifles ran flawlessly through high-round, fast-cadence stages, firing hundreds of rounds with 100 percent reliability and zero maintenance or cleaning. From recoil to reliability, every aspect of performance was improved compared to the typical un-tuned barrel.”

PROOF Research currently offers Caliber Matched Gas System barrels chambered for 6.5mm Creedmoor and .260 Remington in three separate lengths: 20, 22, and 24 inches. Every CAMGAS barrel comes standard with an easy to install custom-length gas tube.

Visit Proof Research