Lyras
17-01-2009, 05:35
Machine Gun, Joint Project 21(MGJ-21) 'Mary-Jane' or 'Marie-Jeanne'
http://i71.photobucket.com/albums/i156/UNDComrade/Yanitaria/Guns/MGJ-21.png
Weight: 8-7.7kg with bipod, 19-18.7 kg with tripod mounting (Depending on barrel length)
Length: 1000mm (standard) or 910mm (Paratrooper)
Barrel Lengths: 450mm (17.72 inch)(standard), 360mm (14.17 inch) (Paratrooper)
Cartridges: 6.5mm JMC, 7.92mm TPF, 7.62R Russian, 6.8mm ASG, 6.8mm SPC, 5.5x 45mm Yanitarian, 7.5x45mm Yanitarian, 7.62x39mm Russian, 5.45mm Russian, 7.62mm NATO, 5.56mm NATO, 6mm Remington, and 6.5mm Grendel.
Rate of fire: 800 or 600rpm, adjustable.
Action: Closed-bolt, short-recoil operated, balanced automatic action
Muzzle Velocity: ~840 m/s, dependent on cartridge
Range: up to 2000 meters with tripod and C2 sight, bipod; 800 meters.
Feed: Disintegrating-link belt- or magazine-fed
Sights: T-section iron sight, dorsal picatinny rail allows alternates. C2 sight available when tripod mounted.
Background:
With the Lyran shift from 6.8 x 43 to the Fedalan standard 6.5 x 45, and arrival of the LY20 and AY144, chambered in that cartridge, the LY19 LMG found itself rapidly falling from favour. While a highly effective piece of equipment in its own right, it quickly became apparent that the need to carry and supply differing ammunition types would negatively affect the logistics and distribution chains. Given a co-existing Yanitarian requirement for an LMG chambered in 6.5 x 45, and given the two state's co-membership of the Accords and geographical proximity, co-operation on development of such a weapon was a logical development.
Yanitaria, having not long switched to the AY144, still possessed very large stocks of the AY20M, a conventionally laid out assault rifle chambered in the appropriate calibre. Initial examinations as to the practicality of re-establishing production of a modified version, as well as refurbishing existing stockpiles, was a great success, and along these lines development proceeded. Early emphasis was placed on accuracy and controllability of the weapon during sustained fire but the national requirements also specified that there be no diminuation in rate of fire or lethality.
Construction
Given the primacy given to the weapon's role as a squad-level light support weapon, and following on nicely from similar initiatives in its AY20M predecessor, every attempt was made to push down the system's carried weight. This lead to the extremely widespread use of synthetic materials. Most parts not involved in the firing cycle are therefore constructed of fibreglass reinforced polyamide. The weapon's barrel, as is becoming the international norm, is cold hammer forged, as are the firing mechanisms and gas system. Anything that can be made out of synthetic materials, without adversely influencing the weapon's reliability and performance, is.
Ammunition
From the outset of the design process, the Lyro-Yanitarian design team sought to make the MGJ21 compatible with as many calibres as possible, so as to facilitate ease of export and distribution, especially to non-JMC-using Fedalan states. This was achieved simply by provision of a number of different barrel, chamber and bolt sizes, while the rest of the weapon remains unaffected. Significantly, the weapons various working parts are unchanged, regardless of the calibre the weapon is firing.
When in Fedalan service, the Mary-Jane is generally chambered in 6.5 x 45mm Yanitarian/JMC. Rounds available in this calibre include, but are not limited to, FMJ, APFJ, JHP and DS. The Mary-Jane can be readily rechambered for a whole host of differing calibres, including, but not limited to; 7.92mm TPF, 7.62R, 6.8mm ASG, 6.8mm SPC, 5.5x 45mm Yanitarian, 7.5x45mm Yanitarian, 7.62x39mm Russian, 5.45mm Russian, 7.62mm NATO, 5.56mm NATO, 6mm Remington, and 6.5mm Grendel.
Operation
The MGJ21 is an air-cooled, closed-bolt, recoil operated, belt- or magazine-fed weapon. Due to this operating mechanism, and given its nature as an closed-bolt weapon, the Mary-Jane tends to accumulate heat faster, but as the weapon features a quick change barrel assembly, new barrels can be quickly be fitted to the weapon, ensuring continued fire despite the lighter-than-standard barrel's rapid heat accumulation.The weapon is loaded from below, by means of insertion of 100 or 200-round disintegrating belts, held in collapsible box magazines. Conventional magazines from an AY20M or AY144 can also be fitted, but an adaptor must first be fitted to the base of the weapon. This adaptor was originally fitted to the right-hand side of the weapon, and rotated into place to receive magazines, however it was awkward and added unnecessary weight, as opposed to simply carrying an adapter.
As the MGJ21 is designed as an accurate, high RoF weapon system, specifically engineered for use as a squad/section-level light support weapon, a factor with a number of ramifications, amongst them the provision for a variety of different barrel lengths to be fitted to the weapon for different combat uses. Also available, as with a number of similar squad-level systems, is a variable, operator-selected cyclic rate. This allows for the user to select which cyclic fire rate is preferred for engagement of whatever target is presented, depending on circumstances. Of the two available settings, the first and highest is 800 rounds per minute. At this cyclic rate, the weapon is usually employed as a burst-fire system, while at the same time allowing for the Mary-Jane to quickly put down heavy suppressive firepower if required. The second setting is also the lowest rate of fire, at 600 rounds per minute. This is the setting normally selected when the weapon is used in close-quarters battle, and presents a more mobile, controllable option. This setting is also used when the operator is low on ammunition. With the magazine adaptor fitted, and a conventional magazine loaded, the Mary-Jane, using this RoF setting, essentially operates as an assault rifle, with very similar performance features to its AY20M ancestor.The VOSCR is achieved by tightening the rollers in the bolt. This is done via a screw system controlled from a wheel just behind the charging handle. In order to control it, the user must press a button on top of the weapon, and turn the wheel forward, to slow the rate down to 600rpm. Afterwards, doing the same thing in the opposite direction will raise the rate back up to 800rpm. Two simple ball detents ensure that the two settings do not require any guess work.
The Mary-Jane uses a balanced automatic recoil system, of the same general type as that employed on a variety of weapons previously designed Yanitarian and Lyran weapons. The system is based on utilisation of a pulley to drive a secondary piston and counterweight in the opposite direction as the motion of the recoiling bolt. The mechanics are such that as the bolt reaches the furthest rearward part of its action (thus impacting the rubber pads of the interior of the butt plate), the counterforce also reaches the end point of its forward movement. This 'balanced recoil' action noticeably decreases felt recoil and thus improves controllability and accuracy in automatic fire. Given that the Mary-Jane is designed to be employed primarily in the automatic firing role, this feature was deemed especially appropriate. As was implemented in the LY20, rubber shock-padding at the rear of the bolt, interior of the butt and contact points for the forward-moving counterweight, further reduce felt recoil, although their absence will not hinder the weapon's operation in a purely mechanical sense. Recoil springs housed in the butt also lower felt recoil, giving the Mary-Jane a very low degree of felt-recoil, a feature which is becoming commonplace in both Lyran and Yanitarian-produced weapon systems.
Barrel and mounting options
The primary barrel is a 45cm (17.72 inch) chrome-lined barrel. 36cm (14.17 inch) barrels exist for CQB combat and high-mobility duties. In defensive positions, the weapon is normally mounted on one of any number of tripods. This allows for better stability and easier use. The Mary-Jane, however, is also meant to be squad portable, and thus a folding bipod is equipped for squad and platoon level uses. The stock of the weapons makes use of a rubber butt, so lesser strain is placed on the user's shoulder. Off the assembly lines, the Mary-Jane uses a three-post, T-section Yanitarian-style iron sight system, which includes both orange and green tritium inserts for night use. A flip-up anti-aircraft sight can also be fitted. Finally a picatinny rail is fitted onto the top of the weapon, allowing for an ACOG, Aim Point, TGTM-4, or other sighting system to be fitted. Other system options include a heat shield, friction buffer, and an advanced muzzle brake, the latter being threaded for the employment of blank-firing attachments, and also functioning as a flash suppressor. Rails can be fitted to the right and left sides of the barrel, as well as below (although the bipod tends to get in the way if one is fitted), to allow a number of first, second, and third party attachments.
Safety
The safety is a simple push-through trigger-lock and bolt-inhibitor, which both prevents the trigger from being pulled and also prevents the firing pin from being released. As a closed-bolt weapon, it does not need to be cocked before the safety can be engaged.
Export
Available from both Lyran Arms (http://forums.jolt.co.uk/showthread.php?t=541320) and Yanitarian Arms (http://forums.jolt.co.uk/showthread.php?t=543091)
Price: $2,000
http://i71.photobucket.com/albums/i156/UNDComrade/Yanitaria/Guns/MGJ-21.png
Weight: 8-7.7kg with bipod, 19-18.7 kg with tripod mounting (Depending on barrel length)
Length: 1000mm (standard) or 910mm (Paratrooper)
Barrel Lengths: 450mm (17.72 inch)(standard), 360mm (14.17 inch) (Paratrooper)
Cartridges: 6.5mm JMC, 7.92mm TPF, 7.62R Russian, 6.8mm ASG, 6.8mm SPC, 5.5x 45mm Yanitarian, 7.5x45mm Yanitarian, 7.62x39mm Russian, 5.45mm Russian, 7.62mm NATO, 5.56mm NATO, 6mm Remington, and 6.5mm Grendel.
Rate of fire: 800 or 600rpm, adjustable.
Action: Closed-bolt, short-recoil operated, balanced automatic action
Muzzle Velocity: ~840 m/s, dependent on cartridge
Range: up to 2000 meters with tripod and C2 sight, bipod; 800 meters.
Feed: Disintegrating-link belt- or magazine-fed
Sights: T-section iron sight, dorsal picatinny rail allows alternates. C2 sight available when tripod mounted.
Background:
With the Lyran shift from 6.8 x 43 to the Fedalan standard 6.5 x 45, and arrival of the LY20 and AY144, chambered in that cartridge, the LY19 LMG found itself rapidly falling from favour. While a highly effective piece of equipment in its own right, it quickly became apparent that the need to carry and supply differing ammunition types would negatively affect the logistics and distribution chains. Given a co-existing Yanitarian requirement for an LMG chambered in 6.5 x 45, and given the two state's co-membership of the Accords and geographical proximity, co-operation on development of such a weapon was a logical development.
Yanitaria, having not long switched to the AY144, still possessed very large stocks of the AY20M, a conventionally laid out assault rifle chambered in the appropriate calibre. Initial examinations as to the practicality of re-establishing production of a modified version, as well as refurbishing existing stockpiles, was a great success, and along these lines development proceeded. Early emphasis was placed on accuracy and controllability of the weapon during sustained fire but the national requirements also specified that there be no diminuation in rate of fire or lethality.
Construction
Given the primacy given to the weapon's role as a squad-level light support weapon, and following on nicely from similar initiatives in its AY20M predecessor, every attempt was made to push down the system's carried weight. This lead to the extremely widespread use of synthetic materials. Most parts not involved in the firing cycle are therefore constructed of fibreglass reinforced polyamide. The weapon's barrel, as is becoming the international norm, is cold hammer forged, as are the firing mechanisms and gas system. Anything that can be made out of synthetic materials, without adversely influencing the weapon's reliability and performance, is.
Ammunition
From the outset of the design process, the Lyro-Yanitarian design team sought to make the MGJ21 compatible with as many calibres as possible, so as to facilitate ease of export and distribution, especially to non-JMC-using Fedalan states. This was achieved simply by provision of a number of different barrel, chamber and bolt sizes, while the rest of the weapon remains unaffected. Significantly, the weapons various working parts are unchanged, regardless of the calibre the weapon is firing.
When in Fedalan service, the Mary-Jane is generally chambered in 6.5 x 45mm Yanitarian/JMC. Rounds available in this calibre include, but are not limited to, FMJ, APFJ, JHP and DS. The Mary-Jane can be readily rechambered for a whole host of differing calibres, including, but not limited to; 7.92mm TPF, 7.62R, 6.8mm ASG, 6.8mm SPC, 5.5x 45mm Yanitarian, 7.5x45mm Yanitarian, 7.62x39mm Russian, 5.45mm Russian, 7.62mm NATO, 5.56mm NATO, 6mm Remington, and 6.5mm Grendel.
Operation
The MGJ21 is an air-cooled, closed-bolt, recoil operated, belt- or magazine-fed weapon. Due to this operating mechanism, and given its nature as an closed-bolt weapon, the Mary-Jane tends to accumulate heat faster, but as the weapon features a quick change barrel assembly, new barrels can be quickly be fitted to the weapon, ensuring continued fire despite the lighter-than-standard barrel's rapid heat accumulation.The weapon is loaded from below, by means of insertion of 100 or 200-round disintegrating belts, held in collapsible box magazines. Conventional magazines from an AY20M or AY144 can also be fitted, but an adaptor must first be fitted to the base of the weapon. This adaptor was originally fitted to the right-hand side of the weapon, and rotated into place to receive magazines, however it was awkward and added unnecessary weight, as opposed to simply carrying an adapter.
As the MGJ21 is designed as an accurate, high RoF weapon system, specifically engineered for use as a squad/section-level light support weapon, a factor with a number of ramifications, amongst them the provision for a variety of different barrel lengths to be fitted to the weapon for different combat uses. Also available, as with a number of similar squad-level systems, is a variable, operator-selected cyclic rate. This allows for the user to select which cyclic fire rate is preferred for engagement of whatever target is presented, depending on circumstances. Of the two available settings, the first and highest is 800 rounds per minute. At this cyclic rate, the weapon is usually employed as a burst-fire system, while at the same time allowing for the Mary-Jane to quickly put down heavy suppressive firepower if required. The second setting is also the lowest rate of fire, at 600 rounds per minute. This is the setting normally selected when the weapon is used in close-quarters battle, and presents a more mobile, controllable option. This setting is also used when the operator is low on ammunition. With the magazine adaptor fitted, and a conventional magazine loaded, the Mary-Jane, using this RoF setting, essentially operates as an assault rifle, with very similar performance features to its AY20M ancestor.The VOSCR is achieved by tightening the rollers in the bolt. This is done via a screw system controlled from a wheel just behind the charging handle. In order to control it, the user must press a button on top of the weapon, and turn the wheel forward, to slow the rate down to 600rpm. Afterwards, doing the same thing in the opposite direction will raise the rate back up to 800rpm. Two simple ball detents ensure that the two settings do not require any guess work.
The Mary-Jane uses a balanced automatic recoil system, of the same general type as that employed on a variety of weapons previously designed Yanitarian and Lyran weapons. The system is based on utilisation of a pulley to drive a secondary piston and counterweight in the opposite direction as the motion of the recoiling bolt. The mechanics are such that as the bolt reaches the furthest rearward part of its action (thus impacting the rubber pads of the interior of the butt plate), the counterforce also reaches the end point of its forward movement. This 'balanced recoil' action noticeably decreases felt recoil and thus improves controllability and accuracy in automatic fire. Given that the Mary-Jane is designed to be employed primarily in the automatic firing role, this feature was deemed especially appropriate. As was implemented in the LY20, rubber shock-padding at the rear of the bolt, interior of the butt and contact points for the forward-moving counterweight, further reduce felt recoil, although their absence will not hinder the weapon's operation in a purely mechanical sense. Recoil springs housed in the butt also lower felt recoil, giving the Mary-Jane a very low degree of felt-recoil, a feature which is becoming commonplace in both Lyran and Yanitarian-produced weapon systems.
Barrel and mounting options
The primary barrel is a 45cm (17.72 inch) chrome-lined barrel. 36cm (14.17 inch) barrels exist for CQB combat and high-mobility duties. In defensive positions, the weapon is normally mounted on one of any number of tripods. This allows for better stability and easier use. The Mary-Jane, however, is also meant to be squad portable, and thus a folding bipod is equipped for squad and platoon level uses. The stock of the weapons makes use of a rubber butt, so lesser strain is placed on the user's shoulder. Off the assembly lines, the Mary-Jane uses a three-post, T-section Yanitarian-style iron sight system, which includes both orange and green tritium inserts for night use. A flip-up anti-aircraft sight can also be fitted. Finally a picatinny rail is fitted onto the top of the weapon, allowing for an ACOG, Aim Point, TGTM-4, or other sighting system to be fitted. Other system options include a heat shield, friction buffer, and an advanced muzzle brake, the latter being threaded for the employment of blank-firing attachments, and also functioning as a flash suppressor. Rails can be fitted to the right and left sides of the barrel, as well as below (although the bipod tends to get in the way if one is fitted), to allow a number of first, second, and third party attachments.
Safety
The safety is a simple push-through trigger-lock and bolt-inhibitor, which both prevents the trigger from being pulled and also prevents the firing pin from being released. As a closed-bolt weapon, it does not need to be cocked before the safety can be engaged.
Export
Available from both Lyran Arms (http://forums.jolt.co.uk/showthread.php?t=541320) and Yanitarian Arms (http://forums.jolt.co.uk/showthread.php?t=543091)
Price: $2,000