Was it a mistake to replace the RPD-44? The old, WW2 inspired machine gun is still praised by a big community around the world today. In this article we will try to look at the question from different angles. But the proper assessment will be done in our upcoming book - Soviet small arms of the Atomic Age. Let's discuss the RPD vs RPK issue.
RPD vs RPK
The determination to substitute the RPD for the RPK or any other firearm is a matter of opinion contingent upon the particular circumstances, demands, and objectives of the governing body or military institution.
Although both the RPD and RPK were light machine rifles designed in the Soviet Union, they differ in appearance and function. Designed for sustained automatic fire, the RPD is a belt-fed light machine gun. In contrast, the RPK is a magazine-fed light machine gun that shares its chambering of 7.62x39mm but features a design reminiscent of the AK-47 assault rifle.
A number of variables may impact the determination to substitute one firearm for another, including but not limited to weight, maneuverability, rate of fire, ammunition capacity, and intended purpose. A desire to standardize weapons within a military or the logistical benefits of sharing ammunition types with other firearms in service may also motivate this development. Let's analyze both machine guns separately and then summarize and see if we can find an answer.
RPD-44 - advantages and disadvantages
The advantages of RPD are rather straightforward. The biggest one is the belt-feeding system, which is always a preferable option for the machine gun. And this is hard to take away from it - the belt-fed mechanism allows for a very aggressive and continuous fire to be delivered at the enemy. As ammunition was supplied in 100 round ammo belts, it was certainly an efficient weapon at the battlefield. And would be better than any sort of magazine fed gun.
Second advantage would be its weight. At just 7.4kg it was a very light weapon for its time and is still light even for today. Maneuvering the battlefield or doing long marches would not be a problem for any military man.
The reliability of RPD is a very questionable topic and not as straightforward as textbook characteristics. While the system of the gun is basically the same as on any other machine guns designed by Dyagterev, the belt itself is a poor copycat from the MG-34/42 belt. Being of a very thin metal, and small enough to hold the 7.62x39mm cartridge, it was prone to damage and bending. This, in turn, would lead to constant stoppages, which are not that easy to deal with. A big number of open gaps in the machine gun did not help either - without being properly sealed, all sort of rubbish could get into the system. In many cases the gun had to be them stripped and cleaned in domestic conditions.
RPK - advantages and disadvantages
The disadvantages of the RPK are usually mentioned as advantages of RPD - the feeding system. The 40 round magazine was not a substitute for the 100 round belt. The 75 round drum was so bulky, heavy, unreliable and complex that it is impossible to find any photos from the Soviet Army where the drum is used on the RPK. So, the 40 round magazines was the main means of the ammo supply for the machine gun. But, there were a lot of them - 8 magazines instead of regular 4 issued to riflemen. And they could be used between both AKM and RPK no problem, as they were well unified.
The rest of the features of the regular 7.62 RPK are actually positive. It is ultra light - 4.5kg, the same weight as any old AK which were still plenty at the time. It has a good bipod and stock for comfortable shooting. It is well unified with the AKM, so there is no need to spend time on any extra training. And of course, it shared same reliability, which is still one level above the RPD.
While both machine guns were good enough weapons, neither of them was perfect. The RPK was just well fitted into the doctrine of the "economically efficient army". However, what is interesting is how popular RPD became outside the Soviet Army - US Rangers and Rhodesian Scouts used it very efficiently. So, to actually make sense of the weapon, the soldier had to be more professional, than a regular Soviet conscript. But this issue will be explored more in the Soviet small arms of the Atomic Age.