US 57mm Gun, M1 & HE?

[Jeff Duquette]

Sorry....just wanted to add that Slapdragon's post is an excellent bit of research.

[rexford]

The Americans may be characterize their 57mm rounds as AP and APC but it actually is an APCBC round, which fully describes the number and type of caps. To say that 57mm ATG fired AP and APC, and 6 pdr fired AP, APC and APCBC, is incorrect.

I am interested in correctly describing the cap situation, so 57mm ATG fires AP and APCBC. The fact that the round has a tracer or HE filler is besides the point when one is discussing the presence of caps.

So if a book says 57mm ATG fires AP and APC, 6 pdr shoots AP, APC and APCBC, they are presenting misleading information.

Technically and actually, 57mm APC should be referred to as 57mm APCBC. Since the Americans did not have an APC round, they very sloppily referred to APCBC as APC (armor piercing with caps). The British practice of designating AP, APC and APCBC is what the 'Mericans should have used.

57mm ATG fires AP and APCBC interms of caps. When one is comparing American ammo to British it becomes very important to fully indicate the caps, a point some authors seem to have missed.

[ 11-27-2001: Message edited by: rexford ]</p>

[rexford]

Kurt Laughlin has posted information on the AFV News site giving the proper designation for 57mm ATG HE rounds:

The US did have a designation for the 57mm HE round, T18E1. User instructions were issued via Technical Bulletin TB ORD 169, dated 21 August 1944, and the round was included in firing table FT 57-C-1 issued on 19 September 1944.

I will ask where the 57mm HE rounds were manufactured.

[rexford]

Kurt Laughlin, on the AFV News site, has noted that 57mm ATG fired cannister rounds, and they were more common than 37mm cannister.

Another issue noted. The potential ammo types for 57mm ATG keep coming out of the walls.

[Slapdragon]

That would imply a large number of canister rounds, I wish I could find some AARs with them in use.

It seems that 37mm armed tanks carried 10% cannister, while 37mm guns in the Pacific could have 50% cannister or more. I now have found references in nearly every Pacific campaign outside of the mainland fighting of the use of the 37mm both on tanks and AT guns to fire canister, and even a discussion of the wounding potential of the round, and now have a dozen cases of Europen use including italy. I still have not found any 57mm or 75mm cases of use, which may not mean anything.

[Jeff Duquette]

<blockquote>quote:</font><hr>I am interested in correctly describing the cap situation, so 57mm ATG fires AP and APCBC. The fact that the round has a tracer or HE filler is besides the point when one is discussing the presence of caps.<hr></blockquote>

If you are truly interested in “accuracy” than you should indicate APCBC-HE-T for the M86. After all some penetrators don’t contain explosive charges and some don’t have tracer elements. So if your intent is to be “correct” then perhaps you should distinguish between rounds that were outfitted with tracer elements and those that were not. It makes a big difference to a gunner and TC trying to sense their own fire if the round is equipped or not equipped with a tracer element. To these folks that “T” is quite important.

In addition it is actually important to distinguish between rounds with explosive fillers and those without. As I know you are aware British APCBC differed from US APCBC in that explosive filler was often removed or not included in the later war British versions of APCBC. Therefore if you are truly trying to avoid being “incorrect” it should behoove you to include or discard that little “HE” notation dependent upon the actual make-up of the round in question.

I am well aware of the M86’s cap situation, and am quite content in this case to employ the truncated nomenclature used in official Tech manuals and ordnance catalogues.

<blockquote>quote:</font><hr> Kurt Laughlin has posted information on the AFV News site giving the proper designation for 57mm ATG HE rounds:

The US did have a designation for the 57mm HE round, T18E1. User instructions were issued via Technical Bulletin TB ORD 169, dated 21 August 1944, and the round was included in firing table FT 57-C-1 issued on 19 September 1944.

I will ask where the 57mm HE rounds were manufactured.<hr></blockquote>

Great information. Thanks for the digging and be sure to thank Kurt. Why don’t you ask if you can obtain a copy of FT 57-C-1. I have a WO around here with dispersion info for the 6-pdr APCBC-T It might be interesting to check to see if there was any difference between the 6-pdr and the 57mm's ABCBC-HE-T dispersion stats.

[ 11-28-2001: Message edited by: Jeff Duquette ]</p>

[rexford]

Here is Kurt's response regarding the origin of U.S. 57mm HE rounds, as noted on the AFV News site:

"2) If you want to know which Army Ammunition Plant made 57mm HE rounds, you'll have to ask the folks in College Park. If you are wondering whether it was British or American made, it was American. The US, as a rule, did not re-designate British equipment. For example, the 6 lb AT gun was listed as the "Mark III (British)" and the ammunition kept the same UK designators. The design of the 2-inch smoke mortar was adopted by the US, but American made mortars and projectiles used M-designations. Even into the 1990's this held true, as some 105mm rounds are listed in the tank TMs with UK L-numbers, and the M119 (or whatever) 105mm howitzer TM notes the difference in nomenclature between the US and UK markings that may be seen on caution plates and such."

Good stuff, and I have thanked Kurt Laughlin many times over. One great researcher.

[rexford]

The reason I went into U.S. cap stuff was to avoid the confusion that many make when they read U.S. APC and think that it is different from APCBC.

I believe that at least one poster on this thread corrected me when I said U.S. 57mm ammo was AP and APCBC, stating that they used APC.

The use of APC for U.S. capped rounds leads to the sort of confusion I just indicated. To be correct and minimize confusion, the British description for U.S. rounds, APCBC, fills the bill.

My intent is not hair splitting accuracy and completeness, it is a definition of the cap situation that is not confusing. The designation for solid shot and HE bursters, or tracers, do not lead to similar confusion and seem straightforward.

The truncated U.S. approach has mislead many and will continue to do so, since APC and APCBC appear to be two different rounds (British 6 pdr fires AP, APC and APCBC).

My point avoids confusion and improves clarity. I continue to strongly suggest that either the British designation be used for American rounds (APCBC), or one might state APC (armor piercing and ballistic caps).

The T33 90mm APBC round is a possible point of confusion. The round is capped, but does not have an armor piercing cap, so has a different cap situation from 90mm M82 "APC". What is the U.S. designation for T33 90mm APBC? Is it AP or APC?

[ 11-28-2001: Message edited by: rexford ]

[ 11-28-2001: Message edited by: rexford ]</p>

[rexford]

The Germans had cannister rounds which were much valued for their use and effectiveness against human wave assaults.

The PzKpfw IVH Universe site, at:

http://ourworld.compuserve.com/homepages/willphelps/Specs.htm

indicates on page 3 that the 75mm L24 gun fired case shot with 960 9mm balls.

[rexford]

The Russian Battlefield site, at:

http://history.vif2.ru/guns/project_1.html

has data on Russian cannister shot, which was fired by 45mm, 57mm and 76.2mm guns. I didn't see anything on number and size of balls, but didn't look too long.

[rexford]

The Russian Battlefield indicates tank and SP gun ammo types on the following site address:

http://history.vif2.ru/guns/defin_4.html

This data can be used with the cannister ammo designations to determine which vehicles could fire the stuff.

[Jeff Duquette]

F.M.vonSenger und Etterlin in his work “German Tanks of World War II” indicates that a canister round was being produced for the early STUG-III’s. I believe Valera indicated he had come across Red Army AAR’s indicating canister being employed against Soviet Infantry in or around Stalingrad.

[Jeff Duquette]

<blockquote>quote:</font><hr>My point avoids confusion and improves clarity. I continue to strongly suggest that either the British designation be used for American rounds (APCBC), or one might state APC (armor piercing and ballistic caps).<hr></blockquote>

My point is simply that M86 APC is M86 APC. There should be no confusion as there isn’t two types of M86 ordnance for the 57mm Anti-Tank Gun. If you are intent on using none standard nomenclature and correcting folks that actually use the official designation of the round than you should use the full ordnance description to avoid confusing whatever folks you are worried about confusing. APCBC-HE-T is the form you seek for the US 57mm M86 round, and APCBC-T for the British 6-pdr round. Ultimately I suspect there are two groups of folks…one group knows the cap situation of M86 APC, and one group (a much-much larger group) that prolly just doesnt care much either way.

[Jeff Duquette]

I just got this from Richard Anderson of TDI (co-Author of "Hitler's Last Gamble" as well as numerous periodicals and articles on artillery). Originally rplying to my question at "OnWar" Forum.

<blockquote>quote:</font><hr>Ammo produced for the US-made 57mm (6-pdr) in the US was:

HE-T, M303 (T18 and T18E1) (HE tracer) 1.845 million rounds

Canister (T17) (produced in very small numbers in April 1944 and Jan-Apr 1945 and possibly never shipped) 22,000 rounds

APC-T, M86 and AP, M70 (the standard AP round) 10.624 million rounds

Note that no APDS rounds were produced for the 57mm in the US. All 57mm APDS rounds in the ETO were supplied by the British. (A December 1944 proposal to the War Department requested that the basic load per gun include 10 APDS rounds.)<hr></blockquote>

[rexford]

Great effort Jeff, that clears up alot of controversies in an authoritative manner.

Thanks for the hard work.

Lorrin

[rexford]

Our book, WW II BALLISTICS: Armor and Gunnery, uses the British system of projectile cap designation since it helps to explain a number of characteristics, such as rounds with a "BC" attached have lowered air resistance and carry better. Ballistic cap.

I made a bigger than necessary deal out of the cap designation business because U.S. APC may be correct nomenclature if one understands U.S. nomenclature but it can cause confusion when American and British rounds are compared. I have also had people familiar with American ammo correct me when I referred to 75mm M61 as APC because the U.S. did not use APC rounds, they were APCBC according to British designations.

Guess that that correction I received stuck with me for over 15 years.

I'll drop the crusade.

[Jeff Duquette]

Lorrin:

Any probability of getting Kurt to part with a copy of those firing tables he had mentioned. FT-57 is not an easy manual to obtain. My FM23-75 has very abbreviated tables for AP and APCBC. Might be interesting to examine the whole ****erie. Aren't you curious as to whether there are any dispersal contrasts between the 6-pdr and 57mm?

[rexford]

After I posted Jeff Duquette's 57mm ammunition information on AFV News site, Bob Smart responded with the following:

"I just pulled the Ordnance Department: Procurement and Supply" Green book off my shelf. On page 152 there is a table of Ammunition Procured 1 July 1940- 31 August 1945. It states that there were 12,321,000 rounds of 57mm gun ammunition produced. Your total above adds up to 12,469,000. That is a difference of about 1% so I think they correlate pretty well. But it doesn't leave much space for any other types of 57mm rounds. If my math is right the split is 85% AP, 15% HE. Seems reasonable to me.

By the way some interesting numbers in the table. There were 1,087,083,000 rounds produced of 'Major Types' ( doesn't include a few minor types such as 7.2", 6", 5.5", & 120mm). The largest amount was 411,302,000 20mm (aircraft). Second was 93,434,000 105mm Howitzer rounds. Third was 78,093,000 37mm (tank, antitank, & canister)! That number surprised me I never realized that 37mm was that important."

It appears that 57mm cannister use was restricted. Funny about the 37mm ammo number, but when one considers how many Stuarts, 37mm anti-tank guns and 37mm armed armored cars were around the numbers seem reasonable. Plus 37mm armed vehicles could hold more ammo and fire it off at a much higher rate of fire than 75mm armed Shermans.

[rexford]

And I forgot to add that it takes more solid shot 37mm penetrations to kill or burn a target than a Sherman's 75mm APCBC with HE burster. So expect more ammo expenditure per knocked out tank.

[Bob Smart]

Since I now can post on this forum, I'll add my own commentsto the discussion.

What surprised me about the 37mm amounts was that from other research I've become accustomed to seeing production and usage of American weapons really pick up in 1944. Until then the 'Arsenal of Democracy' was still ramping up production. This trend has been pretty consistent in Shipbuilding, Aircraft production, vehicle production, etc. By 1944 the 37mm had become a secondary weapon. It was still used in the M5 tank and the M8 armored car but I think the 37mm A/T gun was generally replaced (at least in Europe). I was surprised that the 75mm (tank & antitank) entry to be larger. As I remember it was about 49,000,000 ( The book is at home, I'm at work). By the way there are seperate entries for 37mm (aircraft) and 37mm (antiaircraft) production. Does anyone know if these guns actually used different rounds that were not compatable or was it primarily a packaging issue? I assume that the aircraft rounds came linked ( for the P-39 & P-63) but how would the AA gun rounds be packaged? The main use of them would be on the M-15 halftrack I believe. How was ammo on that mount handled? clips?

Bob Smart (bsmart@xecu.net)

[JasonC]

The 37mm figure probably includes 37mm AA rounds. The US standard medium AA was 37mm at the start of the war, before standardizing on the 40mm Bofors. Many 37mm AA mounts were still in use throughout the war (including self-propelled versions incidentally).

In ammo stats, it is a general rule that AA usage is very high in ammo consumption terms (because so few shells actually hit), indirect fire is next (because the occasions for fire are essentially continuous), and direct fire is far less (because the ratio of kills to shots is comparatively high, and the occasions for firing are comparatively low and rapidly "run through").

The 37mm would include direct fire from thousands of AFVs (Grant, Stuart, Greyhound) plus the standard towed ATGs through 1943 (about), but also quite a bit of AA. In fact, the AA total may dwarf the direct fire ground use total (or perhaps just account for half or so).

[Slapdragon]

The 37mm M3A1 AT gun was replaced by the M1 57mm AT gun in infantry formations by the time of CM"BO. Around 8000 were made (I have seen three different production figures though). The Anti-aircraft weapon is the M1A2, declared substitute standard in 1941. It could use the same ammunition, but rarely used cannister. The 37mm was replaced by the bofors in most ground units, and fiured from a 10 round clip. These weapons share the same ammunition with the M6 family (five different models, all related, but with different M numbers -- functionally similar so everyone just relates them together)) of tank born anti-tank weapons. These 37mm weapons were nearly worthless in tank fights, but where carried by quite a few tanks in the 1944 time span including the M5 light tank, the M8 Greyhound, and in the pacific, the M3 Lee/Grant. Around 20,000 of these weapons where built. These weapons had automatic breaches, but where hand loaded.

The aircraft used the M4 37mm aircraft cannon, The cobra series of aircraft, except the export M-400, used the M4, which fired the same 600 grain shell from a short 145mm long case instead of the standard 225mm case of the anti-aircraft, anti-tank, and tank weapons. The M4 cannon use the standard ground ammunition, and fired from a linked belt. One version of the Cobra, the P-69D, did mount the M9 aircraft cannon which fired the 37mm with a 225mm case, but it was not produced in large numbers.

37mm ammunition was produced until 1949 in quantity for the US government (and afterwards for other governments).

[Jeff Duquette]

Hello Bob:

Thanks for digging into your references and coming up with some actual production numbers.

[JasonC]

"expect more ammo expenditure per knocked out tank"

While this is certainly true, it can't account for any significant portion of the total given, as a little examination will show. Most German AFVs were used in the east, not in the west, since the front was much larger and in operation much longer. Only small armor forces were in action on other fronts until the last year. As little as 20% of overall German AFVs faced the western Allies, meaning around 10,000 vehicles.

Then, few of these can have been killed by 37mm. Because most of this total were in action only in the last year, when 37mm had become a distinct minority of the US AT force (only cavalry and light tanks by then, practically, which saw the least combat action), and the kills would be heavily concentrated in the more capable guns. In the earlier period the 37mm were more numerous, but they were never the only guns in action. British 2-pdr, 6-pdr, and US 75mm (on Grants and Shermans) undoubtedly accounted for the majority of early western kills, between them. Any realistic numbers on these factors will lead to the conclusion that German AFVs KOed by 37mm are on the order of 1000, which perhaps as much again for light armor (halftracks and armored cars, etc). As an upper bound.

But the ammo total is 78 million rounds. That comes to 39,000 rounds per AFV. Even with very low accuracy for direct fire, one will have thousands hitting something per AFV kill. The only possible conclusion is that most of the rounds were not AP fired at AFVs. A small factor of 2-3 times as many penetrations needed for a kill (an estimate based on delivering the same energy to the target, approximately) is insignificant next to the obvious 2-3 order of magnitude difference remaining.

Indeed, US built 37mm vehicles and ATGs in the west vastly outnumber the German AFVs they could possibly have killed (by more than a factor of 10), so it was a rare 37mm vehicle that got even one. There weren't nearly enough AFV targets to "go around" for the total ammo figure. Which means most of the 37mm rounds listed were fired at non-AFV targets. That includes HE at infantry, AP at bunkers and buildings, and especially HE-I at aircraft from M1A2 37mm AA guns, including the Pacific theater. Canister, even if common in the Pacific compared to other round types, can't account for much of the total, simply because there weren't all that many tanks used in the Pacific, 37mm or otherwise, and by late in the war most PTO tanks were Shermans with larger guns.

You aren't going to get to 78 million with AT usage, or anywhere near it. Understand, total German large-caliber (50mm plus) AP varities for the whole war, including the Russian front, is almost an order of magnitude less than that figure. The likely "ammo sink" absorbing all the additional shells, without producing massive numbers of dead items that don't fit in accountings on the other side, is AA fire with all its inherent innaccuracy. Including e.g. spraying barrages ahead of V-1s, vast overkill against late-war Japanese airstrikes, etc.