RG-037 or 7.62x28mm Cartridge: Soviet Version of the .300 Blackout Concept
RG-037 (a.k.a 7.62x28mm) was an experimental Soviet cartridge developed in 1983. Its parent cartridge is the 5.45x39mm. The RG-037 has similar dimensional relation to 5.45x39mm as the .300 Blackout has to .223 Remington. If you apply the .300 Blackout case forming method to the 5.45x39mm cartridge, then you’ll end up with something similar to the 7.62x28mm. The initial prototypes of this cartridge were probably made by cutting the 5.45x39mm case just below the shoulder (28mm) then necking down the cut case to .311 caliber (with some neck turning).
The history of this cartridge begins in 1983 when the Soviet union started “Vintorez” trials to adopt a new integrally suppressed weapon and subsonic ammunition. The designers first experimented with loading 7.62x25mm Tokarev cases with heavier projectiles to make a subsonic round. They shortly understood that this kind of solution didn’t meet the penetration requirements of the trials. They needed a long enough projectile to house a sufficiently large armor-piercing core and at the same time be heavy enough to travel at subsonic speed. The new cartridge also had to be loaded with more powder to propel the large bullet and generate enough pressure to cycle a semi-auto mechanism. So they had to design a new cartridge with greater case capacity than the 7.62x25mm Tokarev had.
This is when the RG-037 was born. It was designed by a man named N.V. Zabelin. The cartridge seemed to satisfy all the requirements and they even started manufacturing it in the Tula Ammunition Plant. However, the minimum penetration requirements for the new weapon/ammunition system were raised even more in 1984, which RG-037 couldn’t meet anymore. That lead to dropping the further development of this cartridge. The successor of RG-037 in the trials was 9x39mm cartridge, which was eventually adopted along with the Vintorez rifle.
I think if loaded with modern powders, this cartridge will perform better and it can be reintroduced at least in the countries which armies use 5.45x39mm caliber rifles. Just imagine an AKS-74U (a.k.a Krinkov) rifle chambered in this RG-037 caliber and suppressed. Although, I would rather go with simply necking up the 5.45x39mm case or factory forming the neck to .311 or .308 caliber. Here is what I mean:
The left round in the above image is what could a .311-5.45x39mm cartridge look like. I used Hornady cartridge images to make this mockup because of my “outstanding” (almost non-existent) CAD designing skills.
An AK-74 rifle (or one of its derivatives) chambered in such caliber could get all the benefits that .300 Blackout gives to the AR-15 platform: conversion requiring only a barrel change, effectively suppressed yet powerful subsonic round, same magazine capacity etc.
Managing Editor Being a lifelong firearms enthusiast, Hrachya always enjoys studying the history and design of guns and ammunition. Should you need to contact him, feel free to shoot him a message at Hrachya@TheFirearmBlog.com
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"I would rather go with simply necking up the 5.45x39mm case or factory forming the neck to .311 or .308 caliber"
Ummm.....if you are loading these yourself, wouldn't it just make sense, and be easier, to take 7.62x39 cases and use a lighter load with a heavier bullet to get subsonic?
I guess, because I am 76 yo, I sit back and look at all of this wheel reinvention with a certain amount of humor! I am not that old........ like to remember invention of gun powder, but I certainly do remember the endless cycles of gun and caliber reinvention. It seems to me that when ever we get a slack point in weapons evolution, we redesignate, or attempt to redesign an already working particular weapons platform, we try and reinvent it and that usually results in a caliber/cartridge reinvention. Some of it is normal progression, and some of it is just pure gun writers/inventors BS to stay in the lime light, and stay somewhat relevant to the current conversation. Say the '03 Springfield 30-03/30-06, improved o the Springfield 1898 Krag 30-40, and the M1 Garand improved and moved on up the weapons chain.....I get it! But the current phase of the wheel reinvention is really getting both bizarre and humorous.....we seem to now have a small caliber weapon, that is a semi-good military rifle in certain situations, and we now want it to shoot all manner of weights and size configurations of bullet combinations. An all purpose rifle to fit all niches of armed combat....AND ALSO nust become the basis of all hunting, sport shooting, home defense, and "Ya just gotta have one of these" rifles! Now it seems, that we haven't been alone in this endeavor, it turns out, in a parallel universe, we have got the Russians doing it too! ALL of this AR Platform reinvention proves we have nothing left in the imagination tank!