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Magnum Air Cartridge (MAC) / Technical



The Inovairtech range of airguns are based around the revolutionary patented Magnum Air Cartridge - the MAC - a self contained power-plant used to propel the chosen bullet or pellet down range. Measuring about the same as a .50 BMG cartridge case (103mm x 20mm) the MAC offers levels of fire-power previously only held by high-power PCP rifles and yet without the constant need to refill the rifle itself


MAC Construction

The MAC's are constructed from a solid piece of high carbon steel bar, drilled out to the specification and threaded M14 at each end. Post machining it is nickel plated to prevent corrosion.

The front and rear connecting pieces are made from 303 grade stainless steel. The front part containing an insert for the chosen bullet or pellet of the correct caliber. The exact dimensions of the aperture depends upon the caliber,

The rear section is machined to accommodate the extraction mechanism and contains the external part of the actuating mechanism, the piston rod assembly which needs to be struck hard in order to initiate the firing sequence. This assembly consists of a front seal arrangement, a rear seal arrangement and a central hollow portion through which the compressed air or dry nitrogen escapes. The unit is made from high tensile CR20 steel and is post production nickel plated.

Unique

The MAC is a fully patented gas cartridge system, differing from earlier types of air cartridge systems such as Brocock / Saxby Palmer in several ways. The most important features being the front filling via a quick release fitting, this provides a simple no dismantling method of both filling with compressed air (or dry nitrogen) up to a pressure 4,500 psi and the simple loading of the cartridge, the same adapter is used across all calibers. Upon firing, the internal hollow piston tube transfers the compressed gas from inside the cartridge to propel the projectile with the proprietary seal arrangement at just under the speed of sound.

The MAC's are hydraulically tested to 20,000 psi to offer a safe regular working pressure of 4,500 psi and a maximum safety pressure of 5000 psi.


Filling

The Magnum Air Cartridge connects rapidly to your SCUBA tank airgun filling valve via a simple adapter quick-release style (Supplied) enabling filling in a matter of a few seconds. You decide the fill pressure that you need in each cartridge and can fill each one at pressures ranging from 2500 psi (170 BAR) to 4500 psi (303 BAR) ready for anything from a back garden practice session to full scale airgun hunting. The chosen bullet (or pellet) is simply inserted by hand (no tools required) into the end of the cartridge post-filling, and the cartridge is ready to load into your Inovairtech airgun and you are ready to fire.



The whole procedure to air-charge and load takes seconds, no dismantling, re-assembly, just plug-in, fill, vent, unplug and pop in the chosen ammunition and you are ready to go. The magnum air cartridge is currently offered in .257 .300 .308 .357 and .40 caliber, with all cartridges sharing the same components and external dimensions. Apart from the opening of the loading end being the same as the chosen caliber cartridge, to allow insertion of the correct caliber of ammunition, cartridges in all calibers appear identical and use the same filling adapters to make the filling of several rifles in any caliber the easiest thing in the world

The table below is an approximate guide to see how many MAC fills you should expect from a variety of cylinder sizes and regulated pressures.





Ammunition Guide / Caliber Selection
The MAC front aperture is sized on each caliber to offer the widest range of soft lead ammunition. For the most effective accuracy and power, the ammunition, whilst sitting snugly in the front aperture, ideally should be fully seated (to avoid air passing) and sized for an exact fit to the barrels grooves. Generally the better the seal, the more effective and consistent the shooting experience.

.257 Caliber
The .257 caliber is designed for long range accuracy and MOA (minute of angle - 1" shot groups at 100 yards) performance. Effective range (under 2" shot groups) is over 150 yards.
The single shot rifle is 47" long (minimum, without buttstock extension) and weighs 10lb. The barrel is precision hammer-forged moly steel and is 26" long. It is rifled (6 grooves) with a 1:14 RH twist with a bore of .250" and grooves of .257"
The frame is constructed of 6061 aluminium, with most parts made from either stainless steel or 4130 steel.
The trigger on the single shot tactical is a single-stage factory set unit that breaks at 1.5lb and has a start to stop travel of under 1/4".
It has been designed for best performance using cast soft lead bullets in the 75 to 90gr range.
Muzzle energy is over 105 ft/lb when filled to 4,500 psi with either compressed air or dry Nitrogen gas.
Best long range accuracy on testing has been found using soft cast bullets (6 BHN) of diameter .257" and 85gr with a round nose flat point (RNFP) configuration, these consistently achieve 1" shot groups at 100 yards.
Certain 0.25 airgun pellets may be used for closer range practice and small to medium game hunting up to 75 yards. Typical shot groups with appropriate pellets (head diameter .251" minimum and skirt diameter of .258") are around 2" at the 50 to 75 yard range and muzzle velocity using 4,500 psi with 43gr pellets is around 1000 fps which equates to around 90 ft/lb.
The use of lighter pellets at maximum fill pressures, will result in the pellets travelling at supersonic speeds (>1100 fps) with inherent loss of accuracy through the trans-sonic region (1000 to 1100 fps), therefore it is recommended to use heavier pellets or lighter fill pressures to avoid these high velocities. For best accuracy it is recommended to select the pellet/bullet weight and fill pressures to achieve 750 to 950 fps.

.308 Caliber (Bullets)
The .308 caliber is designed for long range accuracy and close to MOA (minute of angle - 1" shot groups at 100 yards) performance. Effective range (under 2" shot groups) is over 150 yards.
The single shot rifle is 47" long (minimum, without buttstock extension) and weighs 10lb. The barrel is precision hammer-forged moly steel and is 26" long. It is rifled (6 grooves) with a 1:16 RH twist with a bore of .301" and grooves of .308"
The frame is constructed of 6061 aluminium, with most parts made from either stainless steel or 4130 steel.
The trigger on the single shot tactical is a single-stage factory set unit that breaks at 1.5lb and has a start to stop travel of under 1/4".
Best long range accuracy on testing has been found using soft cast bullets (6 BHN) of diameter .308" with a round nose flat point (RNFP) configuration, these consistently achieve 1" shot groups at 100 yards.


.30 Caliber Benchrest (BR) Pellets
The .30 caliber is designed for long range accuracy and sub MOA (minute of angle - 1" shot groups at 100 yards) performance using match standard .30 pellets.
Effective range (under 2" shot groups) is over 150 yards.
The single shot rifle (MAC30BR) is 57" long (minimum, without butt stock extension) and weighs 10lb. The barrel is precision hammer-forged molychrome steel and is 30" long. It is rifled (6 grooves) with a 1:16 RH twist with a bore of .294" and grooves of .300"
The frame is constructed of 6061 aluminium, with most parts made from either stainless steel or 4130 steel.
The trigger on the single shot tactical is a single-stage factory set unit that breaks at 1 lb and has a start to stop travel of under 1/8".
Caution:- Competition rifles with ultra-light triggers may be prone to accidental discharge if dropped.

Optimum performance is achieved at 3,400 psi with 44 grain pellets and 3,600 psi with 50 grain pellets to maintain a velocity of 845 fps.
Other .30 airgun pellets may also be used.
Typical shot groups with the recommended pellets are around 1/2" at 100 yards range.
The use of lighter pellets at maximum fill pressures, will result in the pellets travelling at supersonic speeds (>1100 fps) with inherent loss of accuracy through the transonic region (1000 to 1100 fps), therefore it is recommended to use heavier pellets or lighter fill pressures to avoid these high velocities. For best accuracy it is recommended to select the pellet/bullet weight and fill pressures to achieve 750 to 850 fps.

.357 Caliber
The .357 caliber is designed for high mid-range (50 yards) accuracy and to deliver high energy on a target at that range. Effective range (under 2" shot groups) is up to 100 yards.
The single shot rifle is 51" long (minimum, without butt stock extension) and weighs 10lb. The barrel is precision match grade molychrome steel and is 28" long. It is button rifled (6 grooves) with a 1:18 RH twist with a bore of .351" and grooves of .356"
The frame is constructed of 6061 aluminium, with most parts made from either stainless steel or 4130 steel.
The trigger on the single shot tactical is a single-stage factory set unit that breaks at 1.5lb and has a start to stop travel of under 1/4".
It has been designed for best performance using soft lead (BHN 6) bullets in the 110 to 130gr range. It is important to note that excellent accuracy results have been achieved with 81 gr JSB .35 match bullets.
Muzzle energy is over 125 ft/lb when filled to 4,500 psi with either compressed air or dry Nitrogen gas.
Best long range accuracy on testing has been found using soft cast bullets (6 BHN) of diameter .357" with truncated cone flat point (TCFP) configuration of 110gr and also 81gr round nose pellets which consistently achieve 1" shot groups at the 50 to 75 yard range.
Other 0.35 airgun pellets may be used for practice and medium shooting at the 50 to 75 yards range. Typical muzzle velocity at 4,500 psi with 82gr soft cast lead bullets is around 800 fps which equates to around 115 ft/lb of muzzle energy. Heavier 125gr soft cast bullets achieve around 700 fps which equates to muzzle energy close to 130 ft/lb.
The higher energies attained with 125-130gr bullets are best reserved for closer range hunting (35 to 50 yards) of up to medium sized game (150lb), where energy delivery is important as the slower bullets tend to demonstrate less accuracy than the lighter alternatives, due to slower transit times from muzzle to target and subsequently a more curved trajectory.

.40 Caliber
The .40 caliber is designed for high mid-range (50 yards) accuracy and to deliver highest energy on a target at that range. Effective range (under 2" shot groups) is up to 75 yards.
The single shot rifle is 47" long (minimum, without buttstock extension) and weighs 10lb. The barrel is precision hammer-forged moly steel and is 26" long. It is rifled (4 grooves for optimum ballistic performance) with a 1:18 RH twist with a bore of .393" and grooves of .401"
The frame is constructed of 6061 aluminium, with most parts made from either stainless steel or 4130 steel.
The trigger on the single shot tactical is a single-stage factory set unit that breaks at 1.5lb and has a start to stop travel of under 1/4".
It has been designed for best performance using soft lead (BHN 6) bullets in the 130 to 165gr range.
Muzzle energy is typically over 150 ft/lb when filled to 4,750 psi with either compressed air or dry Nitrogen gas.
Best long range accuracy on testing has been found using soft cast bullets (6 BHN) of diameter .402" of truncated cone flat point (TCFP) configuration of 140gr which consistently achieve 1" shot groups at 50 yards and 1.5" shot groups at 75 yards.
Typical muzzle velocity at 4,750 psi with 140gr soft cast lead bullets is around 700 fps which equates to around 145 ft/lb of muzzle energy. Heavier 165gr soft cast bullets achieve muzzle velocity approaching 650 fps which equates to muzzle energy close to 150 ft/lb.
The energies attained with 140gr bullets make this a strong recommendation for close range hunting (30 to 50 yards) for up to medium sized game (150lb) where energy on target delivery is important.


Care of the MAC cartridges

Inovairtech recommend the careful handling of the cartridges to avoid damage. Charged cartridges should always be handled with care. Cartridges may be cleaned with detergent and warm water if debris has contaminated the external surfaces. Please ensure all cartridges are fully dried before re-charging. A light coating of PTFE grease on the outside is recommended post washing to maintain the external appearance.




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Pack of 20 MAC
Pack of 20 MAC
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Pack of 20 MINI MAC
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Pack of 10 MAC
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Pack of 10 MAC
Pack of 10 MINI MAC
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Pack of 5 MAC
Pack of 5 MAC
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Pack of 5 MINI MAC
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Pack of 3 MAC
Pack of 3 MAC
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Spare Quick release MAC cylinder fitting (QRF)
Spare Quick release MAC cylinder fitting (QRF)
Our Price: $19.89