Reliability of Crew-served Machine Guns

[Beer_n_Pretzels]

Greetings,

I'm hoping some of the WWII history Gurus and/or BTS reps could shed some light on this situation.

I'm a die-hard British player and nothing warms my heart more than the continuous chatter of a 1912 Vickers machine Gun. The Vickers is the perfect sustained fire support / suppression machine gun. It doesn't have the muderous rate of fire of a MG42, or the sheer stopping power of a 50 Cal, but it just goes, goes and goes. In fact the Vickers can just about be fired non-stop for an average 30 turn Quick Battle. Sounds Good?

I've also read that the Vickers 1912 MG had an amazing reputation for reliability. For example, at the Somme in 1916, the 100th Machine gun company fired non-stop for twelve hours, with not one stoppage. At the end of the action the guns had comsumed an average of 8,300 rounds, totalling 1,000,000 rounds for the entire company" (see p124, John Weeks, Infantry Weapons, Ballantine, 1971).

Based on this excerpt, I decided to do a little test. I set up a firing range and got 10 Vickers MG's to fire non-stop at 10 buildings for 20 turns. 14 Jams were recorded. I then repeated this experiment with German MG42 and the US 30 Cal. The 30 Cal recorded 16 Jams and the MG42s, 13 Jams.

The results suggest there is little difference between the machine guns in terms of reliability. Of course one test is not statistically valid, but it does beg the following questions:

1. How is the reliability of crew-served machine guns reflected in CM? (disregard vehicle mounted MG's)

2. What does a JAM result actually represent? is is an actual stoppage, or does it also represent barrell changes, refilling coolant etc?

3. Was the Vickers MG historically more reliable than the MG42?

thanks in anticipation

[jasoncawley@ameritech.net]

The big difference, of course, is the Vickers was water cooled, while the others are air cooled. There is no question that water cooled allows longer sustained fire before overheating - in return for much heavier weight and a few extra things that can go wrong. But the rest of your comments seem slightly off to me.

For instance, the figure of 8300 rounds on average from each gun, over 12 hours, hardly amounts to "firing continuously". That is 83 belts, or 7 per hour, while the cyclic rate of fire is more like that many rounds per minute. So it represents the usual use of machineguns, firing in short bursts on and off. Even the water cooled guns had to do that to keep from overheating, and also to avoid wasting ammo.

The weight the Vickers packs in its water cooling jacket is made up for in an MG42 team (partially) by extra barrels and kit. Even in squad LMG use, the assistant gunner was issued two extra barrels and a pair of asbestos gloves to change barrels while hot.

The only MGs in the game that can come even close to firing continuously are the vehicle mounted coaxial MGs on tanks and the like, which had several thousand round ammo supplies. But if the trigger were literally held down continually, they would #1 certainly jam and #2 exhaust even a several thousand round supply in about 5 CM game turns.

The limit on MG fire simply is not how fast they can fire at the enemy. It is the available ammo and the heat of the barrel and the proper feed of the belts through the gun. Every CM MG is firing on and off, not continually, even if given a target to shoot at every turn.

As for what a jam represents, it can mean any of a number of things. A twig in the ammo belt fed into the gun, or a twist in the belt breaking the ammo links, or the links and spent brass of the fired rounds clogging the feed or bolt return, or a "cook off" round in the chamber hammered but not fired, or changing barrels on an air-cooled gun, or leaking or steaming coolant on a water-cooled gun, or the tripod falling over. Sometimes clearing a jam is as simple as flipping the gun over and banging stuff loose. Sometimes it is a round stuck in the barrel or a broken firing pin or a pierced water case, etc, and the gun it out for good.

The most common stoppages are not going to vary from one gun to another, since most of them are related to misfeeds. A crewed HMG on a tripod, especially inside a building or bunker, would realistically face fewer of those than a squad LMG, bipod mounted and fired prone from the dirt,sometimes without the AG-loader being where he is supposed to be. But it will happen, and the more often the gun is fired the more likely it becomes.

I suspect CM just makes it random and equal for crew served MGs. There is definitely some abstraction in that. The US M2 50 cal, for instance, was much more reliable than the lighter types, largely because of its considerably lower rate of fire (more can go wrong in one bolt-return cycle if it happens fast). The MG42 with its highest ROF would generally "jam" more often, but it would also clear more easily since many problems can be fixed with a spare barrel, which they carried and the others generally did not.

The crew quality should also certainly make a difference, especially in clearing jams and getting back to firing instead of breaking the gun or giving up. But also, more experienced crews should jam less to start with, because they learned to use shorter, more frequent and aimed bursts instead of long sprays, which kept the gun cooler and reduced jamming chances from feed problems (there usually isn't a twist in 10 rounds of a belt, but in 50 there can easily be - the AG-loader has more time to do his job with shorter bursts).

For what it is worth...