0:00:35 – Least pleasant gun I have ever shot
0:02:51 – Favorite gun to have showcased on the channel
0:03:46 – Why did large militaries have .30 cal at the turn of the century while small countries had 6.5mm?
0:05:35 – How does cylinder gap impact pressure and velocity in revolvers?
Excellent study of this question at Ballistics By The Inch.
0:08:02 – My opinion on the .280/30 British cartridge
0:12:43 – How does the US military nomenclature system work?
0:16:04 – Best rifle for 2-Gun in legally restrictive states
0:19:48 – Will I do a Breda PG/1935 video?
0:21:10 – British .303 wood-core projectiles
0:25:02 – Suppressor history
0:27:41 – Modern proof marks
0:29:03 – Good rifle design that never caught on
0:30:15 – Best loading system other than box magazines
0:32:33 – Were there .38 caliber rimfire pistol cartridges?
0:34:27 – Historical conflict where infantry rifle differences made a big difference?
0:37:39 – International meetups
0:39:30 – Why do people not like the M1/M14 safety?
0:41:19 – Why was the Madsen LMG not used more in WWI?
0:42:56 – My bucket list and unicorn guns
0:46:32 – Was 8×33 the first intermediate cartridge?
0:49:09 – History of the .41 Action Express
0:53:53 – Why the decline of water cooled machine guns?
0:57:38 – Is the strong-spring mechanism for powerful blowback actions valid?
1:00:58 – Why no more octagonal barrels?
1:02:41 – What would my ideal pistol cartridge and action be?
1:05:19 – Why did the Soviets change from 7.62×25 to 9×18?
1:07:50 – Female firearms designers
1:10:38 – Patreon alternatives for supporting Forgotten Weapons
If you want to send something directly, the PO box for both Forgotten Weapons and InRangeTV is:
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1:11:45 – Series on FAMAS development?
1:12:58 – Selfloading black powder cartridge designs
1:14:52 – Most convoluted development history for a rifle
1:17:52 – Why did the US bother replacing .30-06 with 7.62mm NATO?
1:19:27 – Attempts to modernize the Maxim?
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“Female firearms designers”
Technically not firearms designer, but cartridge designer:
Антонина Денисова most widely known design is 5,45×18 cartridge for PSM automatic pistol, but she also worked on other designs:
Hmm. So it the PSM really is a “ladies’ gun” like many Berettas and the Walther PPK?
Well, it is certainly one of the few pistols with a cartridge more powerful than .25 ACP which one could relatively easily conceal while wearing a tight fitting evening gown. So, a pretty good gun for a female KGB or FSB agent trying to set up an oldie but goldie honeytrap…
“Soviets change from 7.62×25 to 9×18?”
Before the adoption 9×18 apparently 7,65 mm Browning (.32 Auto) was also considered, example of weapon for it is Пистолет ТС (Tula, Stechkin):
Created in 1947 for 7,62-mm cartridge, copy of adjective(Browning) 7,65-mm cartridge.
I think it is possibly influence from captured German automatic pistol (Luftwaffe during WWII used various .32 automatic pistols); German influence might be found in Makarov automatic pistol (cf. Walther Modell 8 field disassembly procedure)
Italics in my previous post should apply only to 7,62-mm cartridge, copy of adjective(Browning) 7,65-mm cartridge., not subsequent text.
1940s contenders for Soviet Union automatic pistol description, data and photos might be found here: http://shotgun.com.ua/fire/pm/pm_hist.html
In fact there were technical-tactical requirements given (December, 1945) for 7,65-mm automatic pistol and 9-mm automatic pistol (both for usage of Browning’s cartridges – first for 7,65 mm Browning, second for 9×17 mm Kurz cartridge). 9×18 mm would appear after testing of automatic pistol started.
During testing following foreign design were used: Browning 1910/22, Walther P38 and Sauer 38H (7,65-mm) and Beretta 1934 and CZ 38 (9×17 mm Kurz).
In ergonomics area most designs copied Walther solutions (see photos), all used blow-back principle. None of proposal full-filed all original requirements, but designs by Makarov (both 7,65-mm and 9-mm) and Baryshev (9-mm) were rated high. Makarov design was most reliable, have simple trigger-hammer mechanism, small number of details and short time needed to field-strip.
The major influence on the 9 x 18 Makarov, other than the German 9 x 18 Ultra, was apparently the Belgian FN 9 x 20SR Browning aka 9mm Browning Long in the FN Modele’ 1903 aka Grande Modele blowback automatic designed by John M. Browning. (It was essentially a scaled-up Colt M1903 Pocket Model.) It had been extensively used by the Imperial Russian Army and the police prior to the 1917 revolution, and its external shape, weight, etc. strongly influenced the design of the 7.62 x 25mm Tokarev TT-30/33 service automatics.
Ballistically, the 9 x 20SR was in the same general power range as the Italian 9 x 19 Glisenti round, delivering a 110-gr. FMJ RN at 1,100 F/S for 300 FPE. At the time, this was deemed to be about the most power you could get out of a round intended for use in a straight-blowback pistol without unacceptably high breech pressures.
The 9 x 18 Ultra launched a 100 gr. at 1055 for 250 FPE or so; the 9 x 18 Mak fires a 94 gr. at 1110 for 260.
Red Army research in the early Fifties concluded based on wartime reports that it takes about 250 FPE to inflict a torso wound on an adult male serious enough to disable or kill him. The 7.62 x 39mm round was designed to deliver at least that much energy out to 350 meters.
The 9 x 18 Makarov was intended for use within 50 meters, and under those restrictions its power was deemed sufficient for the purpose of self-defense by officers, vehicle crew members, and others who did not or could not carry a rifle for whatever reason. Making it a blowback pistol on the Walther PP model was mainly a matter of production efficiency.
Having used 9 x 18 Maks myself, I can attest that they are about as effective as a .38 Special standard velocity load (158 gr @ 855 F/S= 256 FPE). Which, in what is essentially a pocket pistol, is probably good enough.
How about the Czech Vz 82 in 9mm Makarov? That seems like an ideal form of the blowback 9mm approach.
In my opinion, the leap from .380 ACP to 9mm Luger performance really isn’t worth the cost and complications it adds to the handgun design.
“ideal form of the blowback 9mm approach”
There is also ОЦ-27 Бердыш automatic pistol using blow-back principle:
it started as multi-caliber (9×18, 9×19, 7,62×25, switch possible by means of replacing few parts, which take ~40 seconds) weapon for Russian military trials, but was not adopted. Anyway development continued, after abandoning 7,62×25 and was finally enter service with police units, where it was appreciated.
Basic data (multiple entry apply for 9×19 / 9×18 PM and 9×18 PMM / 7,62×25 respectively)
Length: 200 mm
Barrel length: 125 mm
Height: 140 mm
Thickness: 35 mm
Mass without cartridges: 950 g
Capacity: 15 / 18 / 18
“Which, in what is essentially a pocket pistol, is probably good enough.”
For pocket automatic pistol for 9×18 Makarov see OTs-21:
“Which, in what is essentially a pocket pistol, is probably good enough.”
For pocket automatic pistol for 9×18 Makarov see МР-448С Скиф-мини:
(2nd photo from top)
It has magazine capacity 8 and fire either 9×18 or 9×17 Kurz
Basic data as follows:
Length (barrel) x height x thickness [mm]: 150(79) x 107 x 32
Mass without cartridges [g]: 590
While gas leakage out of the cylinder gap robs velocity, slide-barrel movement also does. A 9mm revolver will many times produce similar velocities to a comparable tilting barrel autoloader. http://www.handgunforum.net/new-handguns-area/16242-velocity-9mm-revolver.html
If so, breech locking is useless since developed to get use of maximum gas pressure expected from a round. Should nearer velocities got obtained with pistols and revolvers, the causes might be;
– Cylinder gap is so narrow,
– Measured revolver barrel lenght does not contain full cartridge length,
– By cause of leakage through cylinder gap, bullet remains longer time in the barrel and uses more of to be wasted, to be unburned powder charge as increasing the initial velocity. IMHO.
“breech locking is useless”, I wouldn’t go that far. They were using short recoil pistols, a gas operated gun where the breech remains stationary until well after peak pressure would probably give higher velocities. A non gun analogy might be track and field sprinters who put blocks down so they have something solid to push off of. With a blowback or short recoil, some of the pressure is used to move the breech. A locked breech is lighter than a blowback for higher pressure cartridges.
Aside from differences in measuring barrel length in revolvers and pistols, and not knowing what their cylinder gap was, I think a moving breech, in principle, has to lower velocities. Of course velocity isn’t everything, reloading and ammo capacity, among other factors counts for something. IMHO.
The working ability taking from the gas pressure is wasted to beat the gun and by means, the shooter in blowback firearms, whereas in locked breech recoil guns, it is used to unlock the bolt and barrel combination. The recoil force of certain cartridges are all same. What changing is the location, kind of working and interval of time it used. IMHO.
In fact, the above statement can be accepted as uncomplete. Not all the working ability but some of which that turning to movability and not only blowback but on fixed breech guns, and it also should be stated that, recoil locked breech is obtained to keep the breech end fixedly fastened during the highest pressure existing in the barrel along with a well computed recoiling distance.
It depends where you measure the velocity from. Muzzle velocity is normally what we care about. The pressure between the breech face and the bullet gives an “internal velocity”. If you can see the breech face moving, then the two will not be the same. Muzzle vel. + Slide vel. = “Internal vel”. IMHO.
From very beginning, “velocity” refers to “muzzle velocity” and in fact, though Newton laws direct beginning both back and forth move of masses simultaneously, comparation of bullet and slide and fastened barrel masses, the backward movement of recoiling elements should be very small and besides, there it be same amount of pushing force forward as the forwarding bullet remaining in the barrel creating a instant plugging effect excepting the escaping gasses, as keeping the recoiled parts as if stationary. IMHO.
I am not an engineer nor a mathematician but I’ve seen enough of their stuff to realize that the equations that most people use are simplifications. The real equations are about 500 terms long. 🙂 Once the bullet hits the rifling and begins to spin, where does the energy come from? Well, add another term. So momentum, M(1)*V(1) = M(2)*M(2) becomes a different equation. What about the gun rotating in an equal and opposite direction? Friction and heating, bullet deformation and heating? Unequally the energy comes from the bullet side of the equation.
So what is the slide velocity? I don’t really know, except it is too fast to see, and can’t be calculated from the momentum equation without knowing a lot more about what is going on. It is probably best to measure it. If The slide moves 40mm in 2.5 milliseconds (reasonable?) what is the average velocity? I get about 16 m/s. Considering that peak pressure happens around 100 microseconds and drops off quickly, peak slide speed happens very quickly, and is closer to 30 m/s since slide velocity drops to zero at its furthest extent of travel. While I believe the internal velocity is the same for both fixed breech and moving breech, the “muzzle velocity” at 15 feet down downrange is different. Consider a tail gunner in a supersonic aircraft firing subsonic rounds. (Q) What muzzle velocity is measured 15 feet down range? (A) They never get there. Just my opinion.
Was a good discussion bp. Thanks.
“I am not an engineer”
First question: are muzzle velocity means equal for revolver and short-recoil/tilt automatic pistol equal for same batch cartridges?
If I am not mistaken to answer such question so called 2-sample t-test is used, click here:
for our example Group 1 should be filled with revolver data and Group 2 with automatic pistol, then click Calculate Now.
If P-value is greater-equal than 0.95 it means that muzzle velocity means value are equal.
“Was 8×33 the first intermediate cartridge”
Article describing early intermediate cartridges:
notice that taking literally intermediate, that is more powerful that current service automatic pistol cartridge but less powerful than current service rifle, mean that is/not intermediate depend country-for-country.
For example from point of view of Regio Esercito during 2nd World War 9×19 (in MAB 38) might be considered intermediate as it is more powerful than .380 Auto (9×17 Kurz) as used in Beretta Modello 1935, but weaker than 7,35 mm Carcano.
How about a fixed mag FAL with stripper clip+pic rail upper? Unlike SKS and M1 it can mount optics (though longer scopes would interfere with the stripper clip guide).
There actually were stripper clips for the FAL. These were odd, “horse-shoe” shaped affairs, not too different from the chargers for the Italian WWII LMG… One fitted it over the magazines, the attachments were a bit like those on AK-74 15rd. chargers, and then thumbed the 7.62x51mm cartridges down into the magazine. Only a relative handful of FAL users among the legions of FAL using militaries used them. No idea if the Venezuelan 7x49mm Liviano was among them…
That’s the reason companies actually made FAL uppers for civilians with that capability. A smaller number of companies combined that with the standard pic-rail upper modern FALs get. Never handled one but they seem like they’d be a good ban-state option.
Question about .30 vs 6.5mm caliber.
I remember to have read a scanned report from the first part of 20th written by/from a French speaking army. The report explained something like the “smaller” countries could afford to switch to smaller calibres and higher velocities faster than big countries :
-a bit less threatened by neighbours to adopt a weapon system in hurry
-they don’t have to make plans for equipping as much conscripts in hurry
-they were considered more budget flexible (Swiss was given in example)
-they can allow themselves for higher quality/more demanding specs
There were some other hypothesis I forget (as well as where in Internet is this document stored)
“French speaking army”
In France 1890 program to develop self-loading rifle started, for it (among others) 6,5 x 61 cartridge was developed: http://www.cartridgecollector.net/65-x-61-sta-cap
This program did not give result fast enough to replace aging Lebel rifles before outbreak of First World War, but one of it results was Meunier A6 (for 7×57 Meunier cartridge) which was used in combat during that war, although in limited numbers.
One reason for the 6.5mm rounds was that overall they had lower breech pressures than the bigger, more powerful 7.62mm class rounds.
This doesn’t mean much to us today, but at the time they were developed (the 1890-95 time frame)there were a lot of first and second-generation military bolt action designs around, such as the Krag-Jorgenson, M93 Mauser, Mannlicher, etc., that were designed and built mainly to handle black powder pressure levels. As such, chambering them for the heavier, more powerful, and more pressure intense cartridges that surfaced in the 1895-1910 time frame was pretty much a non-starter.
One reason that the U.S. Army developed the M1903 Springfield rifle (an initially “unauthorized” copy of the M98 Mauser action) was that experimental variants of the M1895 Krag-Jorgenson chambered for the still-experimental .30-03 round (predecessor of the .30-06) tended to shear their single locking lug and project the bolt right into the firer’s face ala’ an incorrectly-assembled Ross straight-pull.
Similarly, attempts by the Italians and others to rework the M1891 (Mannlicher-) Carcano 6.5 x 52 rifle to the German 7.9 x 57mm generally had similarly undesirable results. Such reworked Carcanos used to be found quite often in Greece; they were not highly thought of.
The Italian 7.35 x 51mm M1938 was an attempt to get a more powerful rifle round, mainly for use in MGs, while still working within the pressure limitations of actions designed for the 6.5 x 52mm.
The 7.7 x 58mm Japanese Arisaka round developed about the same time (late 1930s) was likewise intended to allow a more powerful round for use in mainly MG actions like the Type 99 (1939) LMG, based on the earlier Type 96 (1936) 6.5mm LMG. In spite of their very Bren-like looks, they are in fact based on the same Hotchkiss patents as the Type 92 (1932) and earlier type 11 (1922) MGs, which were variants of the Hotchkiss “Universal” design, itself intended to use the relatively low-pressured 8 x 50R Lebel rifle round of 1886 vintage.
Interestingly, the Japanese were the only ones not worried about the pressure limitations of their bolt-action rifles. The Arisakas, being variants of the M98 Mauser design, are some of the strongest military bolt-action rifles ever made.
Even the “war emergency” Navy variant introduced in 1943, with a cast-iron receiver, was immensely strong, as instead of locking the bolt lugs into recesses in the receiver, it locked into ones machined into a barrel extension made as part of the barrel itself; all the cast-iron receiver did was hold the bolt and barrel in alignment with each other. Strangely, this very sensible arrangement has rarely been used elsewhere.
If you want to know why there were so many “6.5’s” around, the pressure tolerances of the rifle and machine-gun actions of their development period (1885-95) probably had a great deal to do with it.
The Arisaka barrel extension was likely not used because there were too many other rifles on the surplus market. Why bother spending more development money on recreating what’s arguably the best rifle action on Earth when the current commercially sold designs fit the bill well enough for hunters, police, and the army? It’s not like you’re going to use ridiculously over-charged rifle ammunition on a daily basis!
“Japanese were the only ones not worried about the pressure limitations of their bolt-action rifles”
Wait, remember about Exército Português and their Espingarda 6,5 mm m/1904: https://en.wikipedia.org/wiki/Mauser–Vergueiro
which initially fired 6.5×58mm Vergueiro but starting 1939 they were rebuild for 7,9×57 Mauser to become Espingarda 8 mm m/1904-39.
“Similarly, attempts by the Italians and others to rework the M1891 (Mannlicher-) Carcano 6.5 x 52 rifle to the German 7.9 x 57mm generally had similarly undesirable results. Such reworked Carcanos used to be found quite often in Greece; they were not highly thought of. ”
Some more in depth analysis (unfortunatly, again, only in italian) of Carcanos converted to 8x57js – with abysmal results – both by the Germans at the end of the war, and by private italian companies post war:
What about 357 magnum as an intermediate cartridge? The rim kills it for virtually anything you’d want an intermediate cartridge for (except some hunting applications with lever guns).
As for female designers, Stephanie Kwolek’s invention of kevlar is probably related.
For most convoluted, it may be cheating but how about the modern AR15? Various improvements have come from everywhere, been adopted well after their creation ect..
By the way…the FMAS is a delayed lever action (some what unique) according to Small Arms of the World. In discussion of the .41 AE and it’s derivatives, it would have been neat to have the included the 9×25 (10mm necked down to 9mm) as developed for IPSC competition by Rob Leatham. Interesting ballistics to say the least! Also, having lived in grizzly country, I think the flexibility of the the 10mm as a dual purpose cartridge (woods and normal use) and .45 Colt in heavy single action revolvers and the M92 repro carbines, deserves some extra recognition. Ian, you did mention hot 45 Colts as slipping into the role of intermediate cartridges. I never considered a 9mm for a woods gun.
re: first intermediate cartridges
They weren’t military, but arguably the .30 Winchester Center Fire of 1894 and the .250-3000 Savage of 1915 might be considered among the very first intermediate rifle calibers.
“They weren’t military, but arguably the .30 Winchester Center Fire of 1894 and the .250-3000 Savage of 1915 might be considered among the very first intermediate rifle calibers.”
Taking in account also hunting or target cartridge, make question of this intermediate cartridge probably unanswerable with single cartridge name/designation.
.32-40 Ballard might be probably also considered intermediate as, when it was introduced (1884) it was intended for usage with rifle and was less powerful than “full” rifle cartridges (like .45-70), this also true for .38-55 Winchester.
“might be considered among the very first intermediate rifle calibers”
I would add 8.2×45 Krnka:
it was used in Krnka Auto-Rifle, its ballistic are ~150gr @ ~1800 fps (according to thread at vintagesemiautorifle board about that rifle)
While in high school I read Sydney Smith’s autobiography Mostly Murder. That was over 40 years ago, but I do remember him stating that while working in Egypt he noted that the .303 would shed it’s aluminum tip in a victim when shooting at close range.
He began seeing corpses with wood pulp tips, and informed British authorities that the new cartridges were not being loaded with the proper aluminum tips.
Some one informed him that the change was appropriate, and that the wood pulp tip had been properly sterilized prior to manufacturing the bullet. He was in Egypt from 1917 to 1928, so I assume the change was made at that time.
He did not address the terminal ballistic advantage of a rifle bullet with a lighter weight tip. My understanding of this design is that it was indeed developed to improve the terminal ballistics of that bullet.
re: action suitable for black-powder cartridge semi-automatic
How about a Browning type long-recoil action semi-automatic shotgun? Black powder fouling in a shotgun bore wouldn’t be as much a practical drawback as it would for a rifle.
re: best rifle for two-gun matches in States (like California) with restrictions on rifles
I would recommend the Ruger Ranch Rifle in 5.56mm with detachable 10 round magazines and an optical sight.
About the FAMAS.
I quote the excellent suggestion seen in commment on your Youtube channel :
“Justin Maciakil y a 11 heures
Re: the FAMAS….check out the Weapons Department in the Museum of Art and Industry in Saint-Étienne, France.
You can also try to contact the guy who manage(d) this websites :
http://armesfrancaises.free.fr/sommaire.html (last update June 25th 2010)
Most of the current service rounds enable only 2 milimeters of free blowback travel if some 350 grams of slide with engaged parts used in an 11 centimeters of barrel. This means, even without a return spring, the rear of the empty case can unsupportedly travel backward only in a distance that remaining within the thick web of cartridge case base during the highest pressure in the barrel exists. The gained high speed of recoiling slide should be slowed down to minimize the damage occurable at both the frame and the slide and therefore at the holding hand and this can be carried out by the springs formed as stiff as possible. These power sources would harden to manipulate the slide for initial loading and reflect the stored high energy to the returning stage of slide as giving an equal level of avoided strike harming both itself and barrel and therethrough, the frame. This meaans, the unavoided punch of recoil at rearward recoiling travel stage is got at through the forewards and using strong return springs in pistol size firearms seems useless. Service Astra pistols are perfect samples for this drawback and most of them carry thin hairy cracks at their slides. This kind of slowing measures should be cleared off in the current handgun manufacturing philosophy and todey’s trend might be thought as using other slowing effects as gas brake, hesitation lock and one side only shock absorbers getting along with the fixed barrel with examples like; Walther PPC, Remington New51 and HK VP70. IMHO.
About spotting rifles: they were also used range finding devices on heavy recoilless rifles. Optical rangefinders were expensive and slow to use, but the relatively low muzzle velocity of recoilless guns necessitated some form of range finding at longer ranges (beyond about 500 meters). The .50 caliber spotting rifles closely matched the ballistics of the HEAT shell and could be used for fast and relatively inconspicuous bracketing of the correct range for firing the actual gun.
“.50 caliber spotting rifles closely matched the ballistics of the HEAT shell”
For 106mm M40 recoilless rifle, .50 spotter M48 cartridge was used, cut-away photo: http://cartridgecollectors.org/cmo/cmo08dec.htm
notice that is shorter than .50 Browning cartridge, as it is designated to imitate 106 mm shell trajectory. Also notice priming system – powder ignition is in middle rather than in bottom.
Municion entry on this cartridge (as 12,70 x 76 mm):
overall length is given as 113,90 mm. Judging from photos it was used by several West countries, which is not surprise as M40 recoilless rifle, was used by several countries.
Municion has also entry for .60 XM108 Spotter cartridge:
which is .50 Browning necked-up to 15 mm (.60″), there are photos of 2 examples, all are from 1959. There is not data for which weapon it was intended.
Germans has also 14.5 mm Kleinkanone:
firing 14.5x20R, for artillery crew training
Maxim modernizations: while there were no attempts to convert the Maxim to a much lighter GPMG I am aware of, there were nonetheless attempts to modernize the Maxim. The most well-known would of course be the Vickers gun, but since the original question was about post-WW1 guns, I will address that.
The most significant post-WW2 Maxim modernizations were the Finnish M/31 AAMG, M/32-33 heavy MG and the Soviet PV-1 aircraft MG, which was during WW2 used as an AAMG. All of them had a significantly increased rate of fire (900, 850 and 750 rpm, respectively) for engaging aircraft, which was attained with a accelerator. The Finnish ones also used metallic belts, which greatly increased reliability in temperatures around the freezing point. Fabric belts first becoming moist and then freezing to stiff was a problem that was observed already on WW1 even on the Western Front. They also tended to be less reliable at high rates of fire in general.
The Soviets turned some Maxim guns into an LMG–well, OK, lighter anyway, with an aircooled barrel. I believe Tokarev oversaw this project. As far as I can tell, these were provided to the Ejército Popular de la República Española during the Civil War in the 1930s. There are many photos of these in use.
Hence they were called MT for Maxim-Tokarev: https://en.wikipedia.org/wiki/Maxim–Tokarev
“most significant post-WW2 Maxim modernizations were the Finnish M/31 AAMG, M/32-33 heavy MG and the Soviet PV-1”
Shouldn’t be post-Great War?
“Finnish ones also used metallic belts”
This also true for Swiss MG 11 (revision 1934/1935)
Yes, post Great War or WW1.
“The most well-known would of course be the Vickers gun, but since the original question was about post-WW1 guns, I will address that.”
For post-WW1 development I would add Japanese Type 97 aircraft machine gun (not to be confused with Type 97 tank machine gun, which was gas-operated):
it is said to be licensed copy of the Vickers Class E machine gun, which was developed from that well-known Vickers machine gun, considering that it fire 900 rpm rather than 450 rpm, strongly suggest that it was somewhat altered. Does it used metallic belts?
The Army Air Force Type 89 did use metallic belts, so I would suppose the later Navy Type 97 did as well. They fired a different cartridge in a typical wacky Imperial Japanese military manner, but quite likely the Type 97 was still based on the Type 89. Even if it wasn’t, I doubt they could have reached 900 rpm with fabric belts.
Dont remember any female gun designers who invented succesfull product by herself. But there was female engineers who worked in research teams. Russian APS (АПС) underwater rifle is good example, designed by group of ЦНИИТОЧМАШ [tsniitochmash] engeneers including men (А. А. Дерягин, И. П. Касьянов, В. И. Зубачев, П. С. Королев, Ю. П. Воронин, С. П. Лобжанидзе [Deryagin, Kas’yanov, Zubachev, Korol’ov, Voronin, Lobzhanidze]) and women (Г. П. Шамина, Т. М. Михайлова, З. Н. Андреева [Shamina, Mikhaylova, Andreeva]).
Must be others out there.
Not related to the topic.
There was great materials about american M9 and japanese WW2 flamethrowers. Are another models planed to be filmed (soviet, german, british designs), or it is unaccesible in US?
P.S. Sorry for bad english.