Weapon Name- BR-55
Round Type- 8.6mm x 93mm Caseless
Over-all length- 33.5 inches, 26 inches
Barrel length- 27.5 inches, 20 inches
Weight- 13 lb, 11 lb
Rate of Fire- Semiautomatic
Feed Mechanism- Detachable box magazine
Round Capacity- 20
Effective Range- 1100 meters
Range- 2000 meters
Accuracy- 1 MOA
Accessories- Picatinny Sights, Integral Sights
Quick switch firing mechanism- N/A
Scope/Sights- Picatinny Sights, Integral Sights
Muzzle Velocity- 940 m/s (16.2 grams), 7100 joules - 895 m/s (16.2 grams), 6400 joules
Firing System- Long stroke gas piston
Miscellaneous/electronic information- The weapon is based on the TKB-022PM firing system, one of the shortest bullpup firearms in the world. The system was known for it's accuracy and controllability, as well as it's competent reliability, in addition to it's small size.
Basic Information
The weapon is based on the TKB-022PM firing system, one of the shortest bullpup firearms in the world. The system was known for it's accuracy and controllability, as well as it's competent reliability, in addition to it's small size. The BR-55 fires the .338 Lapua magnum rifle round, an extremely powerful rifle round that ordinarily would require too large of a firearm to be realistically carried by an average soldier. Due to the nature of the operating system however, the recoil is extremely light and the weapon is unusually short, thus making it practical for the average soldier. The overall length of the mechanism is a mere 6 inches when the muzzlebreak and shoulder pad is included, dramatically reducing it's overall length. Typically the rifle length is a mere 33.5 inches long, roughly comparable to an M4 carbine, although a carbine variant exists that is only 26 inches long.Typically the rifle is designed to use a 27.5 inch barrel in the marksmen role, however a 20 inch long barrel variant exists for close quarters combat. The weapon also utilizes an
Ak-108 style recoil reducing mechanism, which uses a forwarding reciprocating mass to help stabilize the weapon and reduce the felt recoil of the firearm by counteracting the forward momentum of the bullet. The weapon incorporates many features found on the
Mk-18 and
FR-F2 Sniper rifles, as well as other notable changes designed to increase accuracy and ease of use.
The overall firing system is based on the TKB-022PM, which uses a vertical cyling U-saped bolt and extractor in order to shorten it's overall length. The weapon's distinctive appearance of loading rounds from the rear of the weapon comes from it's mechanism, a feature which would ordinarily be impossible given that most firearms possess a rear cycling mechanism. This gives the weapon the overall length similar to a revolver or break action in length, only requiring a few inches of space in order to operate. The weapon is also significantly lighter, and due to a lack of rearward reciprocating parts during operation has much less recoil, in combination with it's short overall operation. When combined with the muzzle break which reduces the recoil by 30% and the Ak-108 style forward reciprocating mass, the weapon's recoil is significantly reduced, giving much greater accuracy on follow up shots and reducing the fatigue incurred by the user making the weapon controllable under stress and easier to train with. This system uses a recoil-reducing countermass mechanism with two operating rods that move in opposite directions, thereby providing "balance", known as the Balanced Automatics Recoil System (BARS). One operating rod, the upper, has a gas piston facing forward while the lower also has a gas piston. The gas tube at the forward end of the handguard is double-ended to accommodate the two rods. The enlarged gas tube cover of the upper handguard guides both rods in their travel. When the rifle is fired, gas is tapped from the gas port to enter the gas tube, driving the bolt carrier to the rear and the counter-recoil upper rail forward. The critical timing of the reciprocating parts is accomplished by a star-shaped sprocket that links and synchronizes both components, causing both to reach their maximum extension, or null point where forces are exactly equal, at exactly the same instant. The felt recoil is therefore eliminated, enhancing accuracy and assisting control during rapid fire. In combination with a recoil buffer like that used in the HK45 which reduces felt recoil by 30% and a muzzle break, the felt recoil is virtually eliminated, making it very controllable under fire. Due to the use of a caseless round the weapon does not need to eject a cartridge upward in to a forward ejection tube, and thus the overall mechanism is simpler, smaller, more reliable, and has a lower profile.
The weapon possesses a polygonal, cobalt chrome flow-formed barrel, utilizing a 1 in 10 inch (1 in 254mm) right-hand twist, with three groves and progressive rifling, to provide the best accuracy and stability out to long ranges possible. The cobalt-chrome barrel is incredibly heat and wear-resistant, and in military tests an example barrel was shown to fire 24,000 rounds in 30 minutes, at approximately 800 rounds a minute, heating up to 1100 degrees without significant wear, a treatment that would have destroyed most ordinary steel barrels. This barrel longevity and durability aids when using the high pressure and high powered sniper round, and combined with cryogenic treatment and polygonal rifling, allows the barrel to last over 50,000 rounds. The polygonal rifling also reduces friction in the barrel, further reducing it's heat build-up, and in combination with the gain-twist decreases the overall friction of the rifle, and thus it's heat build-up. The gain or progressive twist starts off slower at the first 4 inches of the barrel and gradually increases, and then tightens at the very end of the barrel for the last 4 inches. As most of the stresses on a barrel are in the throat and end of the barrel, the progressive twist not only reduces wear but makes the bullet transition to the rifling more smoothly, thus increasing the accuracy as well as reducing the wear and heat build up. All of these features combined make for a very wear and heat resistant barrel, that maintains it's high accuracy for 10's of thousands of rounds. The barrel is freefloating, and is detachable in a similar manner to the
Tavor rifle, with a locking key system, and can be removed in 2 minutes by an ordinary soldier. In addition, it's muzzle break contours to the rifling of the barrel, thus reducing gyrostopic destabilization of the bullet as it immediately exits the rifle, like on the FR-F2 sniper rifle.
The .338 Lapua caseless cartridge is incredibly powerful and with an incredibly long range, possessing a very high ballistic coefficient of .768, and a muzzle energy of 7100 joules (16.2 grams, 940 m/s) from a 27.5 inch barrel, and a muzzle energy of 6400 joules (16.2 grams, 895 m/s) from a 20 inch barrel. The propellant utilized is more powerful than standard propellants used in the original .338 Lapua Magnum, and burns more quickly, allowing it to achieve greater power from a shorter barrel. This powder comes from the .25-45 Sharp an M855A1 rifle round, which is more powerful per grain, has a more consistent burn, is more thermally stable, burns faster in the barrel, while maintaining the same level of pressure. The round can penetrate level III body armor at a range of 1100 meters, and easily penetrates through light vehicles like the Humvee, or light barriers like concrete walls within this range. At 2000 meters and beyond the weapon maintains an antipersonnel capability, and the
longest confirmed kill with the cartridge was about to 2400 meters, which previously bested the longest confirmed kills from the substantially larger and more powerful .50 BMG cartridge. The cartridge is also very accurate, achieving sub 1 MOA with the standard round, although it can be very expensive, at nearly 2 dollars per round. The cartridge provides not only improved accuracy, but a substantially longer range over most rifle rounds, and improved power, giving it the ability to engage difficult targets behind cover and out to extremely long ranges. The weapon's small size allows the weapon to be used by infantry, along with it's substantially reduced recoil, but nonetheless usually is not used as a main battle rifle.
In addition, the weapon is designed to be used with the XM25 airburst firing scope and platform, enabling the weapon to have an "integrated" thermal scope allowing for automatic aiming or to program air bursting grenades. While the electronic equipment is not integrated in the weapon directly, it can be added with relatively little ease, and be used much in the same way that it was designed to be used on the XM29, largely by replacing the pistol grip. This also allows for grenades to be fired easier, as the firing controls are next to the trigger and pistol grip for ease of reach. The same thermal vision scope can also
double as an automatic aiming device, which in combination with a laser range finder automatically aims the firearm. The weapon uses a
Blackbox round counter that can be linked to various elements of the soldier's gear to display the remaining number of rounds the soldiers have. The magazines are generally color coded, which provides indication of how many rounds are within each magazine, although loading in another magazine that does not meet the criteria can result inaccurate round counting predictions; the round counter mechanism itself, however, will not falter. The weapon uses an extendable stock in a similar manner to sniper stocks. Despite being a bull-pup, several multiple point guiding stocks are used to allow the user to adjust the pull of the stock up to two inches. While extendable, the stock adjustments must be made by loosening and tightening multiple facets, making extending or retracting the stock take a relatively large amount of time, and is similar to a sniper stock in this manner. While picatinny rails are integrated into the weapon, many attachments are expected to be used with the weapon, regardless of the versatility of the system.
