Interdynamics MKR

[Famaldehide Face]

Hi all!

Just asking, Is the ballistics of the 4.5x26mm MKR as good as the .223NATO?. I like the idea of the small ammo having power, making good magazine capacity and cheap to produce. Below is some information i found about it.

Caliber: 4.5x26 mm Rimfire (special ammunition)
Action: blowback
Overall length: 840 mm
Barrel length: 600 mm
Weight: 3.0 kg less magazine
Rate of fire: no data
Magazine capacity: 50 rounds

The Interdynamics MKR assault rifle was another unsuccessful and unconventional design of the Swedish company Interdynamics AB. Interdynamics MKR assault rifle appeared during 1980s on the top of the "micro-caliber" craze. The idea behind micro-caliber (less than 5 millimeters / .20 inch) ammunition was to achieve high velocity, flat trajectory and good penetration in automatic weapon, and with low recoil. The Interdynamics cartridge was based on .22 Winchester Magnum Rimfire cartridge case, with curved taper and 4.5mm / .177" caliber pointed bullet, made of solid brass. Lightweight bullet (1.58 g / ~24.4 grain) achieved a muzzle velocity of about 1000 m/s (3270 fps). The effectiveness of this bullet was claimed to be on par with 5.56x45mm bullet at the ranges up to 300 meters. Unsurprisingly, the stopping power of such tiny bullet was questionable at its best, and use of rimmed, rimfire ammunition obviously compromised the reliability of the rifle. As a result, Interdynamics MKR assault rifle remained only in prototype stage.

Because of the relatively low power of this ammunition, the MKR gun was made using simple blowback system. Rimmed ammunition was fed from semi-circular magazines, located behind the pistol grip, so the overall layout can be classified as bullpup. Ambidextrous charging handle was located at the top of the plastic receiver. Carbine version of the MKR rifle was similar in design, but had shorter barrel.

Courtesy of: http://world.guns.ru/assault/as63-e.htm

 

[Wes Janson]

From the sounds of it, you'd probably have absolutely horrible energy levels past 100 or 200 yards or so. Penetration would probably be quite limited, shallow wide wounds, perhaps similar to current MagSafe ammo?

Not tremendously different from the P90/5.7x28 concept.

 

[max popenker]

Here's the piece from original 1978 paper on MKR rifle, explaining its ballistic performance.

By the way, the man who invented the MKR and its ammunition later went over the great sea and settled in the USA, and now is a master-mind behind most (if not all) Kel-tec brand products

 

[Anteater1717]

Wasn't he also involved with
Intra-tec

 

[PercyShelley]

Seems like there was at least some quantitative basis for the claims of killing power. Was it well known at that time that fragmentation, and not tumbling, was the primary mechanism of injury for M193 ammo?

 

[CBS220]

I've heard that this cartridge was the inspiration for the .17 HMR.

That's not correct so far as I can tell, and the .17 HMR is based on the .22 WMR case, but there are some similarities.

 

[PercyShelley]

I would love to see how this cartridge performs out of a more typical bolt action rifle. Minus the really huge 19th century cartridges, this sounds like the king of the rimfires.

 

[Nolo]

In the report, they can't even spell "ensuring" right, so I wouldn't really pay much attention to them.
A curious footnote in gun history. I'd go with a P90 over it any day.

 

[45ShooterRFB]

In the report, they can't even spell "ensuring" right, so I wouldn't really pay much attention to them.
A curious footnote in gun history. I'd go with a P90 over it any day.

I can think of only a dozen or so things I'd rather have than a P-90. It's more expensive and heavier than a Carbon 15, bulkier than all pistols and the ammo is twice as expensive as surplus 5.56X45!
What I would really like to buy is one of the MKR prototypes I test fired way back when! Now that was a real fun gun and ten times as effective and nice as a P-90! Lighter too!

 

[max popenker]

wow, that's a real case of a Zombie tread resurrection

as for MKR, why not to ask Kel-tec to resurrect and redesign MKR in .17 HMR
of cause, commercial .17HMR ammo is noticeably less powerful than 4.6 Interdynamic, but at least it is widely available from commercial sources; and as it is less powerful, the "New MKR" possibly could be made using simple blowback action instead of the original gas-operated one (the original text on my website is wrong in this regard; will fix it shortly)

Updated to add: fixed my old text, see http://world.guns.ru/assault/swed/interdynamics-mkr-e.html

 

[gotigers]

17 WSM might be worth it, if the cartridge takes hold in the market.

 

[Gtscotty]

So if the 4.6 was based on the 22 mag case just like the 17HMR, how did it achieve velocities probably 1000 fps higher than the 17 (hard to guess what a 17 could do with a 26gr bullet). They must have been running really high pressures, I'm surprised that the 22 mag case could hold together.

 

[max popenker]

how did it achieve velocities probably 1000 fps higher than the 17

High pressures and rigidly locked chamber

 

[Field Tester]

Max,

Sorry to go a bit off topic but what a cool website. My neighbor and shooting buddy is a former Marine that married a girl from Moscow.
I've had a few discussions about firearms and would love to show her your website.
Thank you for making it.

 

[Gtscotty]

I second that, I've been looking at your website for years to read about unusual and interesting weapons. Thanks for going to all the effort to compile all that data.