SX27A2 Caseless Sniper Riflepicture
Round: 8x63mm CFC
Barrel length: 800mm
Rifle twist: 1/10inchs
Overall length: 1360mm
Weight (gun empty, without scope): 6.1kg
Magazine capacity: 10 rounds
Fire modes: bolt action
Features: Adjustable stock with rear support, S-RIS, high efficiency muzzle break.
The upgrading of the SX27 sniper rifle to an A2 model is driven by the unveiling of one of the Crookfur munitions production community's dirty little secrets: That the 8x67mm CFC designation actually applied to two similar but utterly incompatible rounds. Both rounds were of the same dimensions and general performance the only significant difference being the priming method. Initial lots of the 8x67mm CFC ammunition used in the SX27A1 and some early SX26 machine gun models were percussion primed whilst later on production had moved onto an electrically primed version used by all vehicle mounted versions of the SX26 MG and other 8mm weapons systems. After a review it was decided that small batches of percussion primed ammunition would continue to be produced under the designation 8x67mm CFP to allow a limited number of already issued SX27 rifles to remain in service whilst going forward the electrically primed ammunition would be the only standard issue 8mm round. It was apparent that some significant changes would need to be made to the SX27 in order to allow it to use the newer ammunition and so a new variant type was issued for the a modified version.
The SX27A2 now uses a pulsed power system to ignite the primer in its ammunition. When the twin stage trigger is pulled to its first stop the power supply is charged and when pulled to the firing point the circuit is completed sending pulse of electricity through the primer which ignites the booster charge, launching the projectile and igniting the main propellant charge. The electrical priming system does bring an advantage in that it greatly decreases the “lock” time or time between the pulling of the trigger and the firing of the round. The electrical firing mechanism on the SX27A2 can achieve lock times of 20 microseconds or less. Power for the firing system comes from a standard S-RIS battery stored inside the pistol grip.
As the firing mechanism was being upgraded it was decided to fit a new barrel design. The new barrel is of bull profile as compared to the original fluted design. But as it uses improved materials and construction techniques is both lighter and better performing. The inner barrel is still made of steel in now flow formed as opposed to being hammer forged. The flow forming technique greatly improves the mechanical and thermal properties of the barrel and produces more consistent and thus accurate rifling. The inner barrel is surrounded by a carbon overwrap. Made up of PAN carbon fibres wrapped around the barrel combined with pitch fibres and an epoxy resin the over wrap greatly stiffens the barrel and provides thermal performance at least as good if not better then far heavier or fluted steel barrels thus ensuring maximum shot to shot consistency. The overwrap also provides the barrel with an exceptionally robust external finish that can be provided in a range of colours the default being a matt dark (almost black) brown. The barrel also features a revised muzzle brake arrangement utilising a twin chamber pepper pot design.
In terms of other parts of the rifle nothing is changed from the A1 model: the action is firmly bedded to an aluminium “spine” or chassis onto which the stock is attached, a fully adjustable stock with folding mono pod is fitted along with a self levelling bi pod and an S-RIS compatible top rail for the mounting of optical sighting devices.
The result of this is a rifle that is capable of better than 0.5 MOA groupings and is capable of providing lethal effect out to ranges approaching 1500m.
Cost: $16000 (includes: rifle, cleaning kit, carry case and 5 magazines)Ammo data:
Form: telescoped caseless
Standard Loading (13g/200grain and 14.3g/220grain loads are also available):
Bullet weight: 16.2gram (250grain)
Muzzle velocity: 877m/s (2877fps)
Muzzle energy: 6251joules (4611ft pounds)
Super sonic range: 1500metres
Overall round dimensions:
Over all length: 63mm
Overall width: 14mm
Overall weight: 24grams