Grant's "Battle" and World War II Wargaming

I have been re-reading Charles Grant’s “Battle: Practical Wargaming.” It is a good set of rules for World War II wargaming. In fact, three of my mini games are based on it. (Hans und Panzer, Hans und Panzer Afrika, and Krunch a commie - all available here:  http://www.thortrains.net/milihistriot/downloads.html  )

Over the years, I have read and tried several rule sets for the World War II to Modern Era. My first set were the Featherstone rules given in Wargames: Battles and Manoeuvres with Model Soldiers. (British people routinely mis-spell words like maneuvers. They clearly do not understand nuances of the language.)  Nice for a start, but lacking. His second set in Battles with Model Soldiers were actually limited to model vehicles and artillery made by Airfix at the time. So it was on to other rules.

Somehow I had missed Charles Grant’s rules at the time. I did not get a set until almost 20 years ago. Needless to say, I liked them instantly. There were a few bugs, but for the most part, they were excellent. Granted that the original rules were a bit spare, insofar as they only covered a few vehicles in the last year of the War. Extrapolating values for other vehicles and guns was relatively easy. The rules themselves were practical and allowed for a fun game without a lot of useless complexity.

One glitch was how Grant handled the differing armor on the sides and rear of a tank. I prefer a more realistic scenario: In mine, tanks hit frontally are judged by the full Defensive value for that particular vehicle. A side shot is given 2/3 the Defensive Value, and a rear shot is ½ the value.  This takes into account that tank drivers will try to minimize vulnerability insofar as the sides, so that 2/3 is more reasonable than ½. We have to take account of actual armor thickness and the way they were operated. My addition fits the real nature of armored vehicles.

When reading older works, be aware of the hobby situation at the time. There were fewer models available, and that includes vehicles, artillery and infantry. Airfix was the most common source for infantry and 1/76 scale tanks up until the early 1970s. Fujimi emerged around 1972 (that’s when I saw my first Fujimi kit - a King Tiger) Matchbox came a little later. ROCO had the largest line of tanks and had been imported into the US and UK since 1961.
Roskopf was out there, but was not as available in the US.

Everyone made a Sherman or two, Panzer IIIs and IVs, a Tiger, a panther and a T34. You could get them in 1/72 ( Hasegawa ), 1/76, 1/87 and 1/100.  Try to find a Nashorn, Hummel or M7 “priest” and you were out of luck. And while it was easy to get infantry for the major components, they still had not come out with the smaller contingents. You could find US, German and British infantry as well as paratroopers and Commandos, but it was a while before you could find a set of Cafones (Italians) or a Box o’ Bogans (Australians). Folks had to substitute, convert, or make do.

Then there were the “new” 1/285 scale tanks. What fun is wargaming when your tanks are half the size of N scale?

Wargaming itself was about to get cluttered. There were many sets of rules being published. Featherstone, Gygax, Scruby, Grant, Bath, Barker, Quarrie, and a host of others were churning out rule sets for a variety of eras and conflicts. By the mid-70s, there was a glut of rules. All you had to do was walk into the “new” Compleat Strategist and be overwhelmed by the available games and rules.

But I still prefer the old-school rules.

Hans und Panzer, Hans und Panzer Afrika Korps (1939 - 1943) and Krunch a Commie (Cold War ) contain updated Defense Values and Attack Values as well as Speed and Movement tables compatible with Grant’s Battle rules. They cover many of the tanks, other vehicles and anti-tank guns of their respective eras. These games are also compatible with each other.

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There are three subtle jokes included in the above article. Did you catch them?

The Ubiquitous ROCO Schwere SWS Half Track

Older hobbyists will remember the days when scale and availability of models were all relative.

The Military Model Special Law of Relativity, circa 1960 to 1980: If it looks close enough, it will suffice.

The Military Model General Law of Relativity, circa 1960 to 1980: Regardless of scale or the type of item, if it looks close enough, it will do just fine.

SdKfz 250 Half-track

For most of World War II, Germany used two types of armored half tracks. These were the SdKfz (or as we called ‘em: Skid-fizz) 250 and 251 half-tracks. These were used in North Africa, Italy, Western Europe and the East. Look at old pictures of the Wehrmacht and if there is an armored half track, it is most likely a 250 or 251.

Tell that to the small-scale manufacturers!

SdKfz 251 (Bundesarchiv photo)

Early in the game (1961), Austrian model maker ROCO produced the German Schwere SWS heavy half track. This was a large armored half track with angular lines. It looked cool. ROCO made a plain open version, two open versions with the 20mm and 37mm flak guns, respectively, and covered versions. The latter included a “neberlwerfer” rocket launcher, sound detector and searchlight.

The SWS looked great with its sharp, angular lines. As I remember, when first introduced, they were 25 cents each in the local hobby shop. From 1961 to the mid-1970s, these were the only armored German half-tracks in small scale. As such, they were put into model, diorama and wargame service for North Africa, Sicily, Italy, Western Europe and the Russian front. The ROCO SWS half-tracks showed up in miniature depicting battles from 1939 to 1945.

ROCO SWS

UPC and Eldon offered copies of the ROCO half-tracks as kits.

There was one problem. A prototype problem.

The SWS half-tracks did not roll off the production line until late1943. (Sources vary, some saying the SWS was available in late 1943, others in mid 1944.) These were produced in Czechoslovakia, by the way. After the war, the Czechs produced an improved version for themselves.

ROCO SWS Half Track

But Czechs and balances or no Czechs and balances: the SWS was a latecomer. There were none in North Africa or Sicily. No SWS half-tracks figured in the invasions of Poland, France, Greece, the Balkans or Russia. They were not there for the rush to Stalingrad and the Caucasus. The SWS did not appear until after Kursk and Anzio. It may have been available in the West for D-Day.

SWS with Sound Detector

Some hobbyists knew this, but then, there was no other half-track in town. A really good modeler could scratch-build a SkidFizz 250 or 251, but it was a lot of work.  Good luck! For most of us, the SWS was the one and only Heinie Halftrack we could get.

Then came a surprise. A Japanese company called Eidai started exporting kits of the 251 Half track. These were simple. They had few parts and they snapped together. The Eidai 251 was 1/76 scale. At a time when scale was a relative thing, this was a welcome item, indeed! Yet despite the Eidai 251, many an SWS served in the armies of numerous wargames.

SWS Raketenwerfer

Why?

Because history notwithstanding ,we loved the little things!

Eidai has disappeared for a while, but those ROCO SWS half-tracks are still out there in numbers.

Like the song says, “If you can’t be with the one you love, love the one you’re with.”

That is pretty much how we operated in the early days of small-scale vehicles.

So it is with the HO sized ROCO SWS half-track.

(Schwere is what they call obese Germans and Austrians. SWS is anacronum for “Schwere Wehrmacht Schlepper”. In English, that translated to Heavy Army Hauler or Heavy Army Carrier. Schlepper means the same in German and Yiddish. You do not want to be the schlepper. If you have ever lived within 20 miles of New York City, you know what the schlepper is.)

Schwere SWS with 37mm Gun (Compare with SdKfz 7 photo below)

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SdKfz 7 (8t)

Could there be a fluke to justify the SWS prior to late 1943?

Some people may confuse the Schwere SWS with the SdKfz 7 SWS. The SkidFizz 7 was built on specifications laid out in 1932. It was a half-tracked unarmored vehicle that served as a prime mover, personnel carrier, flatbed “truck”, and flak vehicle.  SdKfz7 served German forces throughout the war.

The designation SWS could be the monkey wrench in the works.

The SdKfz 7 Half track started life as an open, unarmored vehicle in several variations. It was used on all fronts as a prime mover and artillery tractor. Fitted with bench seating, the vehicle could tow a field piece and transport its crew. With an open bed, it was also a mount for 20mm and 37mm flak guns. The SdKfz 7 was a workhorse half-track. Some 12,000 were produced.

SdKfz 7 as Artillery Tractor

There were armored variants. Some were local variants produced in battalion workshops. After August 1943, all SdKfz 7 flakwagens were partially armored. On these vehicles, the cab and engine compartment were fitted with 8mm armored plating. (This is about 3/8 of an inch for people who have the good sense to use the SAE system of measurements.) Aside from the gun shield, the rest of the vehicle was unarmored. There were also a few locally-fitted armored prime movers used to haul “bunker-buster” field guns.

SdKfz 7 Flakwagen (late 1943 - 1945)

Compare photos of the armored SdKfz 7 with those of the later Schwere SMS. In the days when scale was relative and vehicle types were interchangeable, one might have passed for the other in a small-scale battlefield. However, we are confronted with two matters of history.

1) The armored-cab SkidFizz 7 flakwagens first appeared in late 1943.
2) The armored prime movers are boxy and look nothing like the Schwere SWS. I have no date on them and assume they were locally-altered variants. I have only seen photos of them carrying the bunker-buster gun.

This fluke of history has been torpedoed! Even something with a semblance to the Schwere SWS did not appear until late 1943.

Still and all, it looks cool!

Unarmored SdKfz 7 flakwagen

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What about the 1/107 scale metal “tank identification” vehicles by Comet / Authenticast? They were not common in the 1960s. Comet / Authenticast was in decline in those years. Very few shops carried them. Very few even knew those vehicles existed. I only learned of the metal Comet / Authenticast tanks within the last 20 years. My first knowledge of tanks like that were the Denzil-Skinner models from Britain that were sold by Henry Bodenstedt”s Continental Hobbies in Farmingdale, NJ. Too small for us! The smallest models my crew used were Roskopf at 1/100.

Comet / Authenticast Panzer IV F2 and F1

Of course, 15mm scale was relatively new at the time and the only examples I had seen were Medieval figures.

Hobbies were not as cohesive as they are now.

Most local hobby dealers specialized in one thing nor another. Our neighborhood shop started as a vendor of model kits and HO scale trains. (I am sure this also happened in Canada and the UK.) Beyond his specialties, he only knew what his distributors advertised. AHM was the biggest importer and distributor around ,which is how hobby shops learned of ROCO tanks and Airfix soldiers. Our shop carried them and sold a lot, but their expertise was in trains , balsa aircraft models and plastic model kits. Even hobby superstores like Polk’s did not display everything they carried. I never saw Comet / Authenticast tanks there. You had to ask for some things. That meant you had to know they were available.(They did carry SAE 30mm figures for a while.)

The inventory of any shop was limited to what the owners’ knew. Our local shop had loads of Aurora monster models and kits for building airplanes, automobiles and ships. They had everything you needed for HO trains. And the soldiers and tanks were mostly what they got from AHM, most of which were Airfix and ROCO. AHM was very good at promoting products to its dealer network, by the way.

Comet / Authenticast US M6 Heavy Tank, M4 Sherman and M3 Half-track

Dealers like Henry Bodenstedt expanded our horizons. I did not know of him until 1972, as his shop was over an hour’s drive from my town. Continental Hobbies imported and sold things that were not widely available. Other than FAO Schwartz, his was the only place I saw Elastolin Figures. Continental Hobbies was our only source for Roskopf tanks.

So it was that we were limited by our local dealers. Indeed, there were ads in the wargaming and military model magazines, but mail order was a bigger pain in the ass than a Celtic girlfriend (Irish, Scottish or Welsh: take your pick. If you dated one you know damn well of which I speak.)  We ordered through our local shops, if possible.*

Another example: getting 25mm metal castings in the 1970s was a trip until the Compleat Strategist opened on 34th street in NYC. They had all the good stuff. It was half historical stuff, half nerdware. You could get Vikings, Romans, and ogres and trolls without the hassles of mail-order.

So it was that many things we might have liked were denied us. We made do with what we could get. People were more dependent on their local hobby dealer than they are today.

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Another problem was the matter of Soviet ordnance. ROCO led off with a Stalin JSIII, and eventually caught up with the T34, T44 and T54 (T55). There were no other vehicles to match them. Roskopf was very uncommon in the US at the time. It was not until the early 70s that we found an importer who carried Roskopf.

Roskopf Soviet T-10 Heavy Tank, 1/100 scale model

That opened a new world to us: T10s, BRDMs and BTRs of every variety. And it had a two-fold effect. Wargamers and other hobbyists had a wider range of tanks, and military personnel had more realistic vehicles for those sand table exercises and such.

Roskopf Soviet BTR 152 w/ dual AA guns. 1/100 scale model

I remember going on a run to a hobby shop for model tanks for sand-table work around `76. I was in the National Guard at the time. The officers brought me along because I had a solid knowledge of tanks, other vehicles, and when and where they were used. Suffice to say I was one of the best at tank identification in the entire battalion. It was a talent I carried over from the Regular Army and my hobby. Some of us had seen the real Soviet stuff up close and personal. If not from seeing it overseas, many Army installations had a few captured Soviet vehicles on display. Fort Drum had a few. Russian death traps, indeed!

Roskopf Soviet KV2 heavy tank, 1/100 scale model

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*Mail order meant sending 25 cents for a catalog and waiting several weeks. Then one pored through the catalog, filled in the order form and wrote a check or money order. Those who mailed cash took their chances. Usually, you had to pick a few alternate items in case the ones you wanted were “out of stock.”

The order took several weeks to arrive, The mail-order vendor usually waited two or three weeks for your check to clear. Most sent parcel post, the slow way. (Any wonder we call it “snail mail”?) Hope that they got the order right. If something was wrong or missing, you had a problem. Send another letter and in cases of exchanges, pack it up and go to the post office to send it back.

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If you found the reference to Celtic Girlfriends amusing, here is an amusing tale from my non-hobby blog: Though this article references women of only one Celtic group, it applies to all of them: http://thorsmanstuff.blogspot.com/2018/05/paddy-beaks-and-viking-descendants.html

Review: Wargaming Airborne Operations by Donald Featherstone,

Wargaming Airborne Operations.  by Donald Featherstone, copyright 1977 Kaye and Ward Ltd.

British Paratroopers, 1944

(A few months ago. I read “A Bridge Too Far” again. Two weeks ago, I saw the movie version again. Seeing a copy of Wargaming Airborne Operations offered, I bought it. Here is my review.)

American Paratrooper with Bazooka

I just finished reading Donald Featherstone’s Wargaming Airborne Operations. It is quite a read - 249 pages. Over 3/4 of the book covers the history, equipment and tactics of airborne operations. That includes coverage of Airborne operations by both sides in World War II. Less than 1/4 is the wargaming ,with advice on everything from troop scale to simulating airdrops. Be advised that this is not a hard-and-fast set of rules. Much is offered as suggestions for further development by the individual wargamer.

One thing is for sure: when you finish reading Wargaming Airborne Operations, you will have a good feel for airborne missions. Featherstone did excellent research into the subject. There is good information on the troops, their equipment and their weapons. Also explained are the types of aircraft and the role of pathfinders and supply drops.

The next part of the book discusses various airborne operations in World War II. It covers small operations as well as Market Garden (Arnhem) and Crete. In one section, Crete and Arnhem are explained in some depth, accompanied by wargame photos.

German Paratroopers

The wargaming section covers everything from movement to firing. It also offers several innovative (and some quaint) ways to simulate parachute drops and glider landings. There are also charts for armored vehicles and the penetrating power of anti-rank guns. This is all “old school” wargaming. It is very straightforward.

The wargaming section is not a cut-and-dried set of rules, however. Many things are suggestions aimed at experienced wargamers. Among these are “Chance Cards’ and “Military Possibilities” which add some of the unpredictable facts or war.

The end includes appendices. One described the structure of German, British and Americans Airborne formations. Another is a brief discourse on realistic battle fields. The last covers sources of miniatures and gear. Several of these no longer exist.

Personally, I enjoyed Wargaming Airborne Operations. It was very informative and certainly made the idea of airborne wargaming more appealing. It gave me new respect for the dangers and difficulties of conducting Airborne operations. I like the fact that the rules can be used with HO, and 1/72 scale troops and vehicles. (Call it what you will, but I was never interested in wargaming with 1/300 scale micro tanks.)

Wargaming Airborne Operations gives a lot of historical information and presents rules that work well with old school wargaming.. Informative and enjoyable, the book will give you insight into the hazards of airborne warfare. A great addition to the wargames library.

Paratroopers in C47 Airplane

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British Paratroopers by Airfix (courtesy of Timothy Hall)

Though I have read of World War II airborne operations in the past, I never read of them together. Wargaming Airborne Operations covers German, US and UK operations one after another. It gives a person a lot of perspective about the vulnerability and dangers of airborne missions. One of the first things that becomes obvious is the high percentage of casualties. Many troops do not make it to their drop zones due to antiaircraft fire. Those that make it face other hazard, from being dropped in the wrong place to landing on an alert enemy.

German Paratroopers by Airfix (courtesy of Timothy Hall)

Airborne operations are risky. In World War II, they were dangerous and resulted in high casualty rates. Everything from falling in lakes to catching anti-aircraft fire made parachuting I get the impression that these kind of missions were often Pyrrhic victories. The training, discipline and leadership of airborne troops have to be intense.

Making Sense of Wargame Small Scales

Minifigs English Civil War figures, 25mm

Aside from the  plastic figure scales mentioned in a previous article, classic wargame figures have been measured in millimeters. There are N - 12mm, 15mm, 20mm, 25mm, 28.8mm, 30mm, 40mm and 42mm. These were the supposed height of a scale figures representing a 6-foot man.

These measurements were not absolute. There was  controversy. Back in the 70s, some makers measured from bottom of foot to top of head. Some measured from the bottom of the base. Others measured to the top of the headgear rather than the head itself. Lack of a standard caused a lot of confusion. One of the common lamest was how one company’s 25mm looked like another’s 30mm, and vice versa.

So-called 20mm scale is actually HO. It is covered in a previous article. (Click here for article:  http://thortrains.blogspot.com/2018/05/small-scale-measurements-simplified.html)

I am including 45mm because it has become popular with toy soldier gamers. Many of the Chinese clones of plastic figures run small, and 45mm has become common as a result. The recast Marx Army Training Set and old Payton figures are 45mm scale.

Some wargame scales equate with model kit and model railroading scales. For all intents and purposes, 25mm = 1/72 scale. 28mm = 1/64 (S Gauge for trains) 30mm = 1/60 scale  40mm = 1/45  scale (German O scale) 42mm = 1/43.1 (British O scale). 45mm = 1/40 (The scale of the old Renwal / Revell military models).

Here is a breakdown of the scales and the size of one scale foot:

N 2mm = 1 scale foot   A 6 foot man is 12mm, or ½ inch tall
15mm 2.5mm = 1 scale foot   A 6 foot man is 15mm tall
25mm  4.3mm = 1 scale foot  A 6 foot man is 25mm tall
28 (28.8) 4.8 mm = 1 scale foot   A 6 foot man is 28.8mm tall
30mm  5mm = 1 scale foot    A 6 foot man is 30mm tall
40mm 6.66mm = 1 scale foot   A 6 foot man is 40mm tall
42mm - 7mm = 1 scale foot    A 6 foot man is 42mm tall
45mm - 7.5mm = 1 scale foot A 6 foot man is 45mm tall

The difference between 28.8mm and 30mm is a mere 1.2 mm. These scales are often intermixed. Likewise, 40mm and 42mm have a difference of 2mm. They are often used interchangeably. 25mm is 4,2 mm different from 28.8mm and 5mm from 30mm. The difference between N and 15mm is 3mm.

Minifigs English Civil War figures, 25mm

A 10-foot vehicle

Let us consider the actual length of a vehicle that is ten scale feet long. Here we see the differences in size clearly.

N - 20mm, Between 3/4 and 7/8 inch
15mm - 25mm. about 1 inch
25mm - 43mm.  1 inch and 3/4 inch
28.8mm 48mm A little more than 1 and 7/8 inches
30mm - 50mm. Almost 2 inches
40mm  - 66mm  2 and 9/16 inches
42mm - 70mm 2 and 7/8 inches
45mm - 75mm - 1.2mm shy of 3 inches

A 40-foot platform

The 40 foot boxcar is one of the standard sizes for model railroading. Consider a 40 foot platform in wargame scales.

N - 80mm - 3 and 3/16 inches
15mm - 100mm - almost 4 inches
25mm - 172mm About 4 and 7/8 inches
28.8mm - 192mm 7 and ½ inches
30mm - 200 mm About 7 and 7/8 inches
40mm - 264mm 10 and ½ inches
42mm - 280mm 11 and 1/16 inches
45mm - 300mm - 4.8mm shy of 12 inches

Minifigs English Civil War figures, 25mm

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If you would like European-style paper house kits scalable for 25mm to 40mm (one is pictured with Minifigs soldiers). click here: http://www.thortrains.net/wargame/download.html

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The main problem with wargame figures is that they are often disproportionate. The heads and hands may be too large. Good, proportionate figures can be used for trackside scenery.

25mm to 30mm figures are scaled about right for use with S scale and Marx O27 “scale” models. The 28.8 and 30mm figures approximate 3/16" to the scale foot. 25mm can be used for shorter people.

40mm are close to 1/48. (A 6 foot man in 1/48 is 38.1 mm, which is 1 and ½ inch.) The difference is 1.9mm.

15mm is TT scale.  TT is popular in Eastern Europe. For instance, TT World War II German Infantry would be scaled right for the old German Reichsbahn. I have seen these trains in TT, made by an East German firm.

Solido and Verem vehicles run about 1/50. For wargaming, they look good with 40mm, 42mm and 45mm figures.

At least one wargame makers has been using 28.8 figures with 1/56 armor. 1/56 is about halfway between 1/48 and 1/64.  A 6' figure in 1/56 would actually be about 34mm tall. Most semi- scale O gauge freight cars run about 1/56 in size. Full 1/48 scale boxcars are notably larger.

Again, one maker’s 25mm might be another’s 30mm. For example, I remember the old Stan Johansen Samurai from the 70s. He insisted they were 30mm, but most folks considered them to be 35mm

Small Scale Measurements Simplified, from 15mm to 1.72

Model Scales - 1/100, 1/87, 1/76 and 1/72

Authenticast 1/100, Airfix 1/76 soldier, early ROCO 1/90

There was a time when ranges of small-scale military models were far from comprehensive. In the 70s, for instance, ROCO had many models of US and German WWII and NATO vehicles. There were few Soviet and World War II British vehicles in its inventory. At 1/100, Roskpof had a very complete inventory of Warsaw-Pact armor as well as a good range of US and German NATO and some World War II. Airfix made mostly World War II, with a variety of US, British and German vehicles and one Soviet piece, the T34. Hasegawa at 1/72 had a few early World War II US pieces and some German armor. A small-scale wargame usually involved a selection of three or four of these scales. KV series heavy tanks in 1/100 were outsized by 1/72 scale Lee medium tanks. Those of us who collected and wargamed small-scale took it in stride.

ROCO, Roskopf and Airfix each marketed soldiers in their preferred scales. Respectively, these were HO : 1/87, 1/100 and OO : 1/76. The size of the figures were notably different. Here is a breakdown of figure sizes, based on the height representing a 6 foot tall man.

1/100 is 3.04 millimeters scale foot. A 6 foot man would be 18.24 millimeters
1/87 is 3.5 millimters to scale foot. A 6 foot man would be 21mm tall
1/76 is 4 millimeters to the scale foot. A 6-foot man would be 24mm tall.
1/72 is 4.23 millimeters to the scale foot . A 6-footman would be 25.4mm tall

That is a 3mm difference between 1/100 and HO. Ditto for HO and 1/76. The difference between 1/76 and 1/72 is 1.4mm. On the other hand, the difference between 1/100 figures and 1/76 is 6mm. It is 7.4mm when compared to 1/72.

Imagine a vehicle10 scale feet long:

In 1/100, it would be 30.4mm long.  That is a little more than 1 and 3/32 inches
In 1/87, that is 35mm long. That is around 1 3/16 inches long.
In 1/76, that is 40mm long. It is a little longer than 1 and 1/8 inch
In 1/72, it is 42.3mm long. That is between 1 and 3/16 inches and 1 and ½ inch.

The difference between 1/100 and 1/72 is 12mm, or ½ inch.

Let us borrow an idea from model railroading. The 40 foot boxcar is a standard. More models of the 40 footer are made than any other boxcar, in every scale from O to N.* 40 foot is distance we can understand. Here we go:

In 1/100, 40 feet is 121.6mm That is almost 5 inches
In 1/87, 40 feet is 145mm. It is about 5 and ½ inches
In 1/76, 40 feet is 160mm. This is close to 6 inches and 1/4 inch
in 1/72, 40 feet is 169 mm. That is close to 6 inches and 3/16 of an inch

There is almost a 1 ½ inch difference between 1/100 and 1/72.  That is quite a lot for small scale models.


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Though they use tanks in 1/100 to 1/109 scale, the actual scale for 15mm figures is closest to 1/120. This is also close to TT scale. Though TT did not lasti in the US, it was popular in Eastern Europe. 15, scale is 2.5mm to the foot.  Therefore , a ten foot platform would be 25mm, almost an inch. A 40-foot platform would be 100mm, almost 4 inches.

The tanks originally used for 15mm gaming were recognition models buy Comet / Authenticast and Denzil-Skinner.  Comet / Authenticast’s 1/109 tanks set a standard for 15mm wargaming.

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Indeed, adherence to precise scale was not always the case up to the late 1970s. This was true even in the 1/35:50mm to 1/29 - 1/30 : 60mm scales. Magazines were usually fussy about scale dioramas. However, it was common in the early to mid-70s to see featured dioramas blending 1/32 and 1/35 models, or HO paired with 1/76 figures. In military models and model railroading, the awareness of scale accuracy has increased since the 1960s.

One example for model railroading was the first run of N scale trains. Scale? Close, but not always. Then again, some of the HO sold in the 50s and 60s was not always close. One maker, IHC (and its predecessor AHM), was known for selling 1/76 scale locomotives as HO scale. (These were actually British style OO - 1/76 made to run on HO track). Scale was a crapshoot in the old days.

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*The 40 foot boxcar was a standard for much of the 20th Century. Many remain in service, though they have been eclipsed by 50" and larger boxcars. Model railroad scales are:

O (American O is 1/48) 1/4" = 1 scale foot
S is 1/64. 3/16" is one scale foot.
OO is 1/76. 4mm - 1 scale foot.HO is 1/87. 3
HO is 1/87.1 3.5mm = 1 scale foot
TT is 1/120. 2.5mm = 1 scale foot
N is 1/160. 2mm = 1 scale foot

Trains that run on G scale track may be:

1/32  3/8" = 1 scale foot.
1/29 10mm = 1 scale foot
1/24 1/2" (12.7mm) = 1 scale foot
1/20 15mm = 1 scale foot
1/22.5 scale, 12.mm = 1 scale foot.