What weapon would you wield?

-First, note that my initial reply to Gaines was in regards to individuals within their own organization and using intrinsic, not captured weapons.
-Second, Gaines did not ask about the use of captured weapons in his original question. Terry D. expanded the scope to include captured weapons. In my initial reply to him I noted; "when it did occur was temporary and was not to the exclusion of the issued TOE weapon (they would not discard it)"

The following is to more fully explain my statements and the reasoning behind them:

Look at the unit of fire figures for US MGs 2000 and 3000 rounds, now the MG34 with a higher ROF would probably require more to keep fully engaged, but lets split the difference, 2500 (makes the math easier also). Now a unit of fire doesn't directly equate to days of supply because the entirety of a unit is not normally engaged in sustained combat on a daily basis. For instance, probing attacks or raids may be made for several days prior to a general assault (where an entire unit of fire or more would be expended). These attacks would fall on individual squads or platoons, or in the case of a battalion individual companies. The company-battalion would then cross level the ammo supply to resupply the effected platoon/squad-company. Each man/crew served had what is now called a basic load, (not sure the WWII term) that every man/weapon is authorized to be supplied/carried prior to engagement. Then the overall unit has a reserve ammo stock which is distributed to the component units on an as needed basis. For an M1 rifleman the "basic load" was 80rds in the cartridge belt and another 96 rds in two bandoliers (bandolier, 6 pockets by 8rd enblock clip, x 2), and I think two hand grenades. To illustrate, first squad gets probed, 2d and 3d squads are not engaged. After the attack the 1st squad leader gets a head and ammo count and his men have expended 50rds per man (roughly 6 clips per man; 6 x 8rds=48). He sends this report up to the platoon Sgt/platoon leader and they order each rifleman in the two unengaged squads to give up two enblock clips, which are then used to replace the ammo expended by the first squad. This is called cross-leveling. You can't do this when non standard weapons are used to permanently replace TO weapons, and one of the reasons behind standardization.
Now that I've diverged from my explaination and confused the issue, back to my original point. So, if your Vickers teams replaced their guns with MG34's, between serious engagements you'd need to acquire ten boxes of MG 34 belted per gun to meet your requirements (German Machine gun ammo came in 50rd belts, 5 belts per ammo box, or 250 rds. Individual belts could be linked). When applied to the specific example of Tobruk, the Germans were poorly supplied and didn't have big ammo dumps to raid, so supply for the guns would be problematic. This number is just to meet the base needs, a unit of fire was not usually adequate for heavy combat and was based upon average ammunition expediture, and modified by theater. Planners/logisticians would actually plan for a given unit to be supplied or built up to, 2-3 units of fire for the initial, heaviest combat or an expected assault. This doesn't directly correlate to planned days of supply because the majority of the time a unit is not engaged in sustained combat daily. For Terry D's, "Tobruk the infantrymen of the 9th Australian Division" example, both sides did supplement their units with captured weapons, equipment, artillery, motor vehicles, etc. this does not mean replaced which is more inline with the question posed initially. No, an Australian unit at Tobruk would not discard their Vicker's guns in favor of the MG34. Yes, the Australian's would supplement their supply of Vicker's guns with captured MG34's. If the truck breaks down, or the gun runs out of ammo, if the item were supplementary you're no worse off than before you captured it. In fact you're probably in better shape for having used up the captured materials while decreasing use of your own. If you replaced your own intrinsic vehicles or guns, what do you do for spare parts when the vehicle breaks, breaks a track, has a flat tire or you use up the captured ammo supply, or a bolt or firing pin breaks, or the feed pawl becomes too worn the feed the belt? The navy wasn't running enemy parts and ammunition into the port.
Logistical constrains were one of the primary reasons for the Germans, they were inadequately supplied, at the end of a long overland supply route from a port with inadequate thruput capacity. For the Australians it was for logistical, and tactical reasons. The garrison was cut off from overland resupply, but did receive adequate resupply by the navy through the port. Getting ammunition up to the forward positions was limited to the times of day during which said movement made enemy observation and attack less likely (during the hours of mirage and at night). For instance, one of the problems that hampered the German's ability to successfully breach the defensive perimeter was actually identifying Australian defensive/fighting positions. If you have a truck drive up during daylight and start unloading, guess what, you just identified a position and a carefull observer could make a reasonable guess from the type of crates/material unloaded as to the numbers and weapons occupying said position. Tactically, if you have two of your Vickers guns set up to cover a minefield with crossfire, and you have a captured MG34 and 400 rounds why not set it up in another location to take an attempted breach in flank? Or emplace it forward in an LP/OP to engage the initial breaching attempts while your Vickers wait, undetected until the attack more fully develops? One of the first things enemy units try and do is locate and silence your crew served weapons. Open fire too early and you expose yourself to neutralization before your fire can be fully effective, too late and you have insufficient time to break up the enemy attack before they're in your lines. Open up peicemeal and the enemy has the opportunity to concentrate their fire against each weapon/position in turn. That's why training and discipline are so crucial.
Another logistical constraint, particularly with regards to machine guns is supply of spare parts, and trained armorers for correcting problems beyond the ability of the gun crew to repair, and the availability of specialized tools, guages and specifications to keep the weapons operable. Most guns required that headspace and timing be set regularly and always after replacing parts like a bolt or barrel. On weapons with a quick change barrel, extra bolts were carried by the gun crews, and had been pre-mated to the barrels by an armorer. Failure to follow these proceedures more often than not resulted in catastrophic failure of the gun. Feed pawls are another part that may require adjustment if the gun runs badly or experiences frequent stoppages or with heavy use are prone to failure,
Another good example of logistics controlling weapons employment is the 1st Marine Division at Guadalcanal. They deployed with the 1903 Springfield instead of the M1. It wasn't because the Marine Corps lacked sufficient M1's to arm the division, because they could have. Or as has been alleged in some historical works, that they resisted the switch to what they perceived as a less accurate semi-auto rifle (though there were individuals that held that view, but individuals unless they hold a position of sufficient authority don't make those type of decisions). The real reason is that they lacked sufficient numbers of trained armorers, and their logistics chain had not accumulated enough spare parts or sufficient .30-06 ammunition in enblock clips to support the proposed operation. Better to deploy with a less capable rifle, that could be kept serviceable and supplied with sufficient quantities of ammunition, than a more capable weapon that might be rendered ineffective due to lack of spare parts and ammunition.

Now for my buddy CAC, here's a good military study on the 9th Australian Divison at Tobruk. I download and keep a lot of these military study pdf's, they're great reference material, and because they're created in a military/educational environment and peer reviewed, heavily sourced, and have a lot of inaccuracies and fallacies that creep into popular histories published for the general public eliminated. They are good background material to provide context to ones reading of popular histories. I think you'll enjoy the explaination of the tactical factors.

http://usacac.army.mil/cac2/CGSC/CARL/download/csipubs/9AustralianDivVsAfricaCorps_Miller.pdf

 

Was just a side point...but learned some new stuff. thanks USMCPrice...and you can call me Luke : )

 

To clear up some confusion in what can be a very confusing topic (gotta hold your tongue just right to keep it straight), it's time to present some period documents. With pretty fuzzy copies, I'll have to do it in more than one post, so stay tuned. Hope it's legible.

This is from the ETO General Board's early postwar 'lessons learned' report. It officially defines 'unit of fire' and 'basic load.' 'Day of Supply' is a bit different - it was used as a high level procurement planning and supply concept. It was the expected overall theater average consumption of ammo per day. A DofS was approved for each type of weapon (and it was updated based on recent expenditure data). If you were the theater ordnance officer responsible for supplying ammo, you didn't care who used it or when - but you needed to know the daily expenditure average (and keep an eye out for developing trends) so you could requisition the right mix of types from U.S. depots. I was somewhat surprised to see ETO .30-06 in 8-rd clips being expended at only 3 rounds/per weapon/per day. What that demonstrates, of course, is that most rifles were only used occasionally - and some hardly at all. When we were all 10 years old with a foxhole in the back yard and a helmet liner on the bedpost, there were no non-combat days - and certainly no non-combatants with rifles. Hard to totally expunge that mindset when looking at theater averages, but dems the actual numbers.

 

Here's the other report - from Third Army's campaign AAR. This states the procedure for using units to replenish their basic loads of ammo. Note that it authorized ammo issuance to replace expenditures based on a written request originated by the using unit.

From everything I've read, this policy is consistent with ETO practice.

 

As I stated earlier, the Unit of Fire was modified by theater. It doesn't really surprise me when you look at Day of Supply though, you've got to figure out of all the rifles in a division (or better yet Corps), only a small percentage are actually up front with the line units. Then subtract even further for the doctrinal employment of two forward one back when employing units. To explain for some of the others, in a triangular organization with three regiments of three battalions with three line companies, it was doctrinal to employ two of the elements forward with the third held back as a reserve. Then you have days with little or no contact, then when there is contact it's not usually the entire unit but an outpost, combat patrol or probe. The fighting in most cases is not protracted. So when you start dealing with averages the number isn't really that surprising.
One thing that did surprise me about PTO numbers I've seen is that a Unit of Fire, as per definition one day of heavy combat the rate for M1 .30-06 is 1 unit of fire but 5 days of supply. However, for the BAR .30-06 was Unit of Fire 750 rounds but 45 days of supply. This would tend to indicate that BAR's were heavily engaged during heavy fighting, but hardly used during times of light contact. The light and heavy machine guns were even worse, they might expend 1 or more units of fire per day during heavy fighting, which as I wrote earlier was 2000rds for a light and 3000rds for a heavy, but when figuring Days of Supply, one Unit of Fire was 150 DofS!

 

In normal army battle order, one Platoon of each Rifle Company was off the line in reserve. One Rifle Company of the three per Battalion was held in reserve. One Battalion of the three per Regiment was in reserve, and of the three Regiments per Division, one of those was held in reserve. I'm feeling too stupid to do the math today, but as you see (in a static situation), those men in contact and in a position to shoot at the enemy were only a minority of the actual riflemen in a Division.

This situation above assumes a static situation, not under attack or attacking. Yet, even in an attack a Division commander would try to keep a Regiment in reserve, and the Regiments attacking (or being attacked) would try to hold a Battalion in reserve.

I'm just throwing that out to keep in context the "three rounds per weapon per day." Those men in actual contact would be shooting far more than three rounds per day.

 

I agree, you just re-explained what I said previously. Only in a clearer manner!

This did apply to attack or defense, and usually went down to the platoon level. In the attack the platoon commander needed a reserve to react to enemy counters such as flanking movements or if the two attacking squads seized the position or broke through, you need someone to exploit the breakthrough or reinforce and add weight to success.

 

I warned you it was confusing.

It appears you may have conflated 'days' with 'days of supply.' DofS is expressed in terms of rounds/weapon/day - it has nothing to do with days directly. 5 is the average number of rounds expended per day for each rifle (rounds, not days). And so on for BAR and MG.

Though unit of fire is a prediction of what might happen tactically and day of supply is a long term average of what actually happened, if you insist on comparing the two, then divide a weapon's unit of fire by its day of supply - that gives a hypothetical number of days of average use (as opposed to the unit of fire's day of heavy combat). So, for the rifle that's 30 days; for the BAR it's about 16 days; and for the MG it's 13-20. Not much difference for such a broad gauge with so many built-in assumptions.

Unit of fire was pretty much abandoned by the ETO while it remained more popular in the Pacific. That may make some sense as a huge ground campaign over an 11 month period allows for expenditure ups and downs to average out while an assault landing by a much smaller force is teetering on the edge of a supply crisis for much of its shorter campaign.

Until proven otherwise, I'll remain dubious that U/F applies to anything but combat units (DofS applies to all weapons).

 

Ah, I see. That makes much more sense. Thank you.
I've seen the charts, but a full explaination did not accompany them. I saw it discussed on Axis History Forum and I went with the explaination for how the two numbers correlated that their debate settled on. It really isn't applicable (as you've said) to anyone but a higher level logistician because the operational unit, be it Co/Bn/Rgt/Div, is only worried about maintaining its supply levels. A particular unit may receive multiple units of fire in one day, or it may receive an initial unit of fire and not need another for weeks or months.

Please elaborate.

Within both the Japanese and German armies a concept similar to the Unit of Fire existed, though not called the same thing, obviously. I've seen some of the Japanese "Kaisenbun" charts and they're quite similar numbers wise to the American ones.

 

PPsh with many rounds

 

I don't believe it. There are no mall ninjas here!

 

American :flag_USAcryingeagle :
Rifleman: M1 Garand
Sniper: M1903A4
Assault Rifle: M2 carbine
Assault: M1A1 Thompson
Support: Browning Automatic Rifle (B.A.R)
Pistol: M1911

British :flag_uk: :
Rifleman: Lee Enfield no.4
Sniper: Lee Enfield no.4 mk 1 (t)
Assault: Sten Gun
Support: Bren Gun
Pistol: Webley mk.VI

USSR :
Rifleman: SVT-40
Sniper: Mosin Nagant m91/31
Assault Rifle: AVT 40
Assault: PPSH- 41
Support: DP-28
Pistol: TT 33

Germany :aa_germany: :
Rifleman: Kar98k
Sniper Kar98k (scoped)
Assault Rifle: STG44
Assault: MP40
Support: MG 42
Pistol: P38

Japan :aa_japan: :
Rifleman: Type 99 Rifle
Sniper: Type 99 (scoped)
Assault: Type 100
Support: Type 11
Pistol: Type 26 Revolver

French Resistance :flag_france: :
Rifleman: Mas 36
Sniper: Mas 36 (scoped)
Assault: Sten Gun
Support: FM 24/29
Pistol: Ruby Pistol

Their are alot of good guns, so I put what I would have taken according to each county.

 

It would be tough carrying all that on your back.