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#21 ElijahWhateley

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Posted 19 October 2008 - 12:46 AM

The drums look like a good idea, but a member on here who knows something about guns mentioned that they can jam up in a certain fashion and are almost impossible to unjam without three hands.


That need not be a problem for every character in CoC...


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#22 ChalkLine

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Posted 21 October 2008 - 01:01 AM

Early model Thompsons (those with the H piece) and Browning Automatic Rifles (also for sale at this time) were fairly delicate and known to jam. Automatic fire was fairly new and such refinements as positive feed and robust magazines weren't really addressed until world war two.

Generally it is possible to empty a magazine of any automatic weapon inside of five seconds (assuming a 50 round drum maximum). Just as generally it is impossible to hit anything with more than the first ten rounds, the 'hosing' seen in movies are usually blanks with far less recoil. The .45 round the Thompson fired is an impressive beastie with a high impulse and slow projectile, both leading to a lot of recoil. Soldiers currently limit bursts to about ten rounds, and many weapons limit the burst to three rounds. I'd seriously rule that unless it's the size of a shantak or an automobile, ten rounds is an amazing amount to get on target.

#23 HANS

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Posted 07 November 2008 - 03:47 PM

You'd use all of the 30 round stick magazine--or all of the 50 round drum.


The 30-round magazine (despite featuring prominently in Glancy's short story "Once More, From the Top" about the Marines in Innsmouth) was not available in the 1920s -- or even the 1930s. It was adopted in late 1941 and not available for service until 1942. The 50-round drum was not too bad, malfunction-wise; but the 100-round drum was pretty terrible; a number of embarrising jams are on record, including the 1926 shooting of "Hymie" Weiss, when the gun jammed after 39 shots . . . Many knowledgeable people at the time, including most of the 1930s gangsters like Dillinger, Nelson, et al, preferred the 20-round box. It was cheaper, lighter, less troublesome, and small enough so that a couple could be carried in the pockets of your jacket (with the gun concealed under it, stock removed).

Cheers

HANS

#24 HANS

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Posted 07 November 2008 - 03:52 PM

The .45 round the Thompson fired is an impressive beastie with a high impulse and slow projectile, both leading to a lot of recoil.


I've fired a Thompson with Cutts compensator (basically equivalent to the Model 1921AC) on semiautomatic (full-auto being forbidden over here), and I found it to have very mild recoil (the thing is extremely heavy). Properly tucked into your shoulder or against your ribs, with a firm hold on both grips, I have now doubt that accurate fire on automatic is possible even with longish bursts.

Cheers

HANS

#25 YunusWesley

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Posted 07 November 2008 - 06:33 PM

(on the 20, 30, 50, and 100 round clips)


Thanks Hans. I quite enjoy the GURPS Pulp Guns book BTW.

#26 deuce

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Posted 06 January 2017 - 02:38 PM

The Winchester Model 1907 was a proto-assault rifle that preceded the Thompson by a good decade. It was used by Mexican revolutionaries and some combatants in WWI. Here's a good blog post on it:

 

http://frontierparti...-assault-rifle/

 

Here's another good site dedicated to "old school" firearms of all types:

 

http://oldschoolguns.blogspot.com/

 

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#27 yronimoswhateley

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Posted 07 January 2017 - 05:02 PM

I've fired a Thompson with Cutts compensator (basically equivalent to the Model 1921AC) on semiautomatic (full-auto being forbidden over here), and I found it to have very mild recoil (the thing is extremely heavy). Properly tucked into your shoulder or against your ribs, with a firm hold on both grips, I have now doubt that accurate fire on automatic is possible even with longish bursts.

Cheers

HANS

 

That was quite my experience with a semi-auto Thompson:  it's very heavy, and the .45 cartridge doesn't push it around very much. 

 

I would have supposed that maybe full-auto at the rates the Thompson is capable of might make a big enough difference to matter, but what I've seen from YouTube videos of Thompsons fired full-auto seems to bear out your impression:

 

 

 

As a casual shooter, the full-auto shooting looks like fun to me, but even I have to admit that it's really a VERY fast way to make 30 rounds of relatively expensive ammunition disappear at the range.  And then, there's the boring, fiddly, and painful little job of reloading the drum mags.  Based on the video, I suppose it would be possible to fire the entire 30 rounds in one RPG round, especially in "spray and pray" mode, but even in 10-round bursts.... 

 

Still, I think the smart thing to do with a Byakhee is to not stand around with a loud and flashy "look at me" weapon punching little annoying holes in it - the smarter (though certainly less entertaining) thing to do is probably to run away faster than the rest of the party, and save the Thompson for clearing trenches full of cultists (preferably while wearing fuzzy chaps and a cowboy hat!).


Edited by yronimoswhateley, 07 January 2017 - 05:16 PM.

"I would have written a shorter letter, but I did not have the time." - Blaise Pascal


#28 HANS

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Posted 08 January 2017 - 07:49 PM

I have a detailed description of my Thompson gun on my blog, in case anyone missed it, complete with game notes for Call of Cthulhu and Delta Green.

 

Cheers

 

HANS


My books Investigator Weapons 1: The 1920s and 1930s and Investigator Weapons 2: Modern Day are available from Sixtystone Press.


#29 Hardrada55

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Posted 08 January 2017 - 08:18 PM

US mercenary in the Mexican Revolution armed with Winchester Model 1907 semiautomatic rifle.

 

[Image link no longer working. ~ mod.]



#30 Nightbreed24

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Posted 09 January 2017 - 08:02 AM

There's a documentary series titled Tales of the Gun which covered the Chicago typewriter.



#31 Celebrim

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Posted 12 November 2017 - 05:18 AM

If you are really a stickler for accuracy, consider the following rules to discourage using the 100 round drum and treating the resulting weapon as a solution to all problems.

Limit the burst size to d12. 

 

For each point of STR less than 12, there is a 5% chance that it requires the investigator a full round to ready and aim the gun before or after firing.  If the investigator tries to fire before the gun is fully readied, then the investigator is spraying and praying that round and only a 1/5 chance of hitting is available.  If the investigator uses the 30 box clip, increase the strength needed to 13, and to 16 for the 50 box drum, and to 21 for the 100 box drum.
For each point of STR less than 5, there is a 5% chance that after firing the weapon results in uncontrolled recoil, and only half the usual number of rounds in the burst are on target.  So, for example, if 12 rounds were fired roll only 1d6 for rounds that hit.  For each round in a burst past the first one, increase the required strength to control the weapon by 1.

 

Require at secret submachine gun skill check to correctly load a 50 or 100 round drum, with failure indicating double the normal failure rate on the weapon when using that drum. 

None of this prevents a burly investigator from using the Tommy as a weapon, but will keep the bookish STR 5 antiquarian from using a weapon that in reality is far too cumbersome for implied strength, or from using large bursts to make up for their relative lack of skill.  Also, the concept may be extended to keep the investigators from walking around with Browning Automatic Rifles if they decide that to solution to scenarios is sufficient firepower.

 



#32 Butters

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Posted 12 November 2017 - 04:14 PM

The original question wasn't about prevention but if you do end up with band of Tommy gun toting librarians and you don't really want to house rule things you may just need to introduce a few more urban scenarios where heavily armed and nervous cops turn up after getting reports of heavy gunfire coming from a house.

 

You could also add things along the lines of Zombies, Mi-Go and everyone's favourite bullet sponge the hounds of Tindalos to show that relying  on firepower alone does not guarantee success. If you are somewhat evil, players going mad can also be used to hint that machine guns might not always be the best thing to bring to an investigation after the B.A.R wielding guy starts to hallucinate that the other Investigators are demons and starts to target them. 



#33 Gaffer

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Posted 12 November 2017 - 05:17 PM

After the 1934 federal law went into effect, it restricted ownership of automatic weapons a lot, as Ames indicated above.

The iconic drum magazines held either 30 or 50 rounds. They reportedly were slow and cumbersome to reload, requiring a manual rewinding of the helical spring. They were also heavy and noisy to carry.

A 20-round stick magazine became available toward the end of the 20s. In 1941 the Army produced a 40-round magazine by welding two 20s together.

Edited by Gaffer, 12 November 2017 - 05:18 PM.

"Two in the head, you know he's dead." <heh-heh>

#34 Celebrim

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Posted 12 November 2017 - 05:40 PM

I personally am far more comfortable house ruling things to take into account actual features of a weapon (like its comparatively high weight and resulting unwieldiness) than I am metagaming against players because I don't like the outcomes.  I suppose both come from a sense that "this thing is too good", but deciding that you need to impose some strength requirements to using a weapon feels very different to me than deciding I need to throw a Color Out of Space or a Hound of Tindalos at the investigators just because they shot a dozen byakhee to pieces and weren't horrified to the extent I find "proper".  I don't feel the need to punish the players for 'winning'.  Given how fragile investigators are, they are sure to get splattered eventually by something.

 

The original question to me really is asking, "About how long do you think a round in Call of Cthulhu actually is?"  I'm sure that doesn't have a fixed answer, but "a second or two" has always felt roughly right to me.   And in that case, the investigator probably can't get off 30 shots in a single round even holding the trigger down.   Twenty perhaps, depending on how more closely you adhere to the idea of "a couple seconds" rather than "about a second", but to me such large bursts as 30 or 50 or even higher imply cycle rates much higher than what otherwise seems to happen in about a rounds time.



#35 HANS

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Posted 12 November 2017 - 07:38 PM

After the 1934 federal law went into effect, it restricted ownership of automatic weapons a lot, as Ames indicated above.

The iconic drum magazines held either 30 or 50 rounds. They reportedly were slow and cumbersome to reload, requiring a manual rewinding of the helical spring. They were also heavy and noisy to carry.

A 20-round stick magazine became available toward the end of the 20s. In 1941 the Army produced a 40-round magazine by welding two 20s together.

 

Er. No and no. I realise real Thompson tomes like Helmer's The Gun That Made the Twenties Roar (1969), Hill's The Ultimate Thompson Book (2009), or Herigstad's Colt Thompson Submahine Gun Serial Numbers & Histories (2014) are expensive and/or difficult to get but there is really no reason to make things up. The drums held 50 or 100 rounds. The first magazine, available from 1921, was the 20-round box. Those 40-round weld jobs don't exist. Seriously, all this is covered both in my blog post --with photos of a real, actual M1928A1 that I shoot regularly, as well as the 20-rounders and 50-round drum -- and in Investigator Weapons 1.

 

Cheers

 

HANS 


My books Investigator Weapons 1: The 1920s and 1930s and Investigator Weapons 2: Modern Day are available from Sixtystone Press.


#36 jlynn

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Posted 12 December 2017 - 06:17 AM

The original question to me really is asking, "About how long do you think a round in Call of Cthulhu actually is?"  I'm sure that doesn't have a fixed answer, but "a second or two" has always felt roughly right to me.   And in that case, the investigator probably can't get off 30 shots in a single round even holding the trigger down.   Twenty perhaps, depending on how more closely you adhere to the idea of "a couple seconds" rather than "about a second", but to me such large bursts as 30 or 50 or even higher imply cycle rates much higher than what otherwise seems to happen in about a rounds time.

 

However, if we go with the Cyclic rate of fire already given in this thread ("600-800") then, in two seconds, anywhere from 20 to 26 rounds can be fired in that period.  If the cyclic rate is something along the lines of an M-61 Vulcan, then you're looking at roughly 200 rounds in the same time period.

 

Bottom line isn't the number of rounds you put down range, but the number that can actually hit something.  (Mind you, putting a lot of rounds down range has it's own charm, especially for cultists, but maybe not if you're up against Byakhee or other Servitor Races that can shrug off a lot of damage.)  To a large degree, fully automatic weapons are more a psychological weapon than they are a physical one -- all that lead flying about tends to keep everyone's head down; but again, that really only works against foes that consider all that lead a real problem.  Hysterically courageous soldiers (or insane cultists) can and will disregard it in the heat of battle (look at all those Marines charging machine gun nests in the 20th century), and creatures that consider it more like an annoyance will probably just be...annoyed.  Unless you can get a significant number of rounds on target in a nice tight grouping and thus injure the creature.  And that's where being "fully automatic" is more of a hindrance than an asset. Those nice tight groupings tend to just go away when you rock and roll with a hand-held weapon. 



#37 yronimoswhateley

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Posted 12 December 2017 - 11:04 AM

At close ranges, the Thompson at full-auto is apparently surprisingly controllable (link), thanks to it's heavy weight: it doesn't seem to climb very much at all.  (Of course, it's fair enough to wonder whether the effective ranges in this video, about ten or so paces, I suppose, are practical Call of Cthulhu ranges:  how many Call of Cthulhu nasties would you want to stand that close to?)


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#38 Celebrim

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Posted 12 December 2017 - 03:10 PM

However, if we go with the Cyclic rate of fire already given in this thread ("600-800") then, in two seconds, anywhere from 20 to 26 rounds can be fired in that period.  If the cyclic rate is something along the lines of an M-61 Vulcan, then you're looking at roughly 200 rounds in the same time period.

 

Bottom line isn't the number of rounds you put down range, but the number that can actually hit something.  (Mind you, putting a lot of rounds down range has it's own charm, especially for cultists, but maybe not if you're up against Byakhee or other Servitor Races that can shrug off a lot of damage.)  To a large degree, fully automatic weapons are more a psychological weapon than they are a physical one -- all that lead flying about tends to keep everyone's head down; but again, that really only works against foes that consider all that lead a real problem.  Hysterically courageous soldiers (or insane cultists) can and will disregard it in the heat of battle (look at all those Marines charging machine gun nests in the 20th century), and creatures that consider it more like an annoyance will probably just be...annoyed.  Unless you can get a significant number of rounds on target in a nice tight grouping and thus injure the creature.  And that's where being "fully automatic" is more of a hindrance than an asset. Those nice tight groupings tend to just go away when you rock and roll with a hand-held weapon. 

 

However, if we go with the original question, "Can I empty a 30 round magazine in a single round?", your answer still gives the negative reply, "No."   If you assume about a second for a round, then a rate of fire of 10-12 on full auto is reasonable.  If you assume about 2 seconds, then a rate of fire of 20-24 on full auto is reasonable which I in fact said in the post you are quoting ("Twenty perhaps...").

 

While 20-24 rounds down field is a lot, its important that it isn't 50 or 100 rounds down field in a single round, which you'll sometimes find players arguing for.

 

As for the tightness of the grouping, the Tommy is a very heavy weapon - a good deal heavier than a typical shotgun or rifle you might have hefted.  Firing pistol ammunition all that weight gives it a very manageable recoil, it can pretty much put everything into a 1 meter target at 15 meters.  Recoil is not a significant problem for a man of average strength, although as with most automatic weapons I wouldn't give one to a kid.  The more significant problem is hefting one into firing position, especially with the heavier drum magazines.  That's why I suggested a 1 round delay in readying the weapon for low strength characters.

 

I disagree that automatic weapons are simply spray and pray weapons.  In the hands of unskilled users, maybe, but not every one emulates the Hollywood movie style of holding a weapon at your hip and shaking it back and forth as if the gun magically hit everything you looked at.  At close combat ranges, automatic weapons in the hand of a skilled user are accurate.  At battle ranges up to 400 yards, they are 'inaccurate' in a sense, but at that range are area of effect weapons in that all of that lead is falling into a fairly small strip say 2m wide by 20m long.  At longer ranges, up to 2000 yds, a heavy machine gun - especially one with tracer ammunition - can be used to create 'beat zones' where anyone treading in the zone is likely to take a hit from all that lead.  The more lead you are putting down range, the more likely you are to hit everything in the zone - which is why you have very high rates of fire on things like an M-61.  From the perspective of an infantrymen, the problem with full auto is that its not a terribly efficient use of your ammo and you'll soon run short.

 

The idea that automatic weapons are primarily "psychological" weapons is absurd.  During WWI a great many very brave men charged across open ground quite fearlessly, and were cut to pieces by automatic weapon fire regardless of how stoically they braved the balls.  Automatic weapon fire doesn't cause men to loss their nerve.  It causes men that don't find cover quickly to die.  It suppresses the enemy because the alternative is to get cut apart.  There are situations where units lose their nerve and go to ground without cover, which is pretty pointless since you are going nowhere and you'll run out of men usually before the enemy runs out of bullets, but they are doing so not simply because of the sound of the fire, but because they are exposed to a deadly hail of bullets and often have very visual confirmation of that fact.   However, machine guns work just fine at killing infantrymen that don't consider all that lead a real problem.  Marines successfully charging machine gun nests were exceptions rather than the rule, and they usually succeed by a combination of speed and information overload on the part of the machine gun team.

As for automatic weapons versus mythos monsters, if you allow very high rates of fire, most of them get torn apart quite quickly by automatic weapons.  A Vickers machine gun can easily kill a Lesser Outer God or any of its servitors.   Most Mythos creatures have some sort of resistance to firearms that let them stride up and kill an investigator plinking away with a pistol before they take much damage.  But very few actually can wade through accurate fire from a submachine gun or assault rifle.  Generally you'll find something of the following:

 

~6 armor: This works well against pistols as the odds that a couple of bullets from low caliber pistols will do significant harm is small.  It even works decently against shotguns or rifles if you are within a few yards and there aren't more than 3 or 4 investigators.  It doesn't work against automatic weapons, because you can put so many bullets on target in such a short order that unless the monster is basically in a closet with the investigators, they'll get torn apart before they can go far.  To be effective, you need armor of 8 or higher, or armor AND one of the defenses below.   If the armor is like 3 or 4, the thing is dead.   Best strategy versus high armor targets is big game rifles.

 

Half Damage: This works OK against most firearms and such as it gives the monster a round or two to get close and personal.  But again, it doesn't work that well against automatic weapons.  As I mentioned in another thread, there is a big difference between expecting to do 10-20 damage per investigator and expecting 40-80 damage per investigator.  Half of 40 damage is still going to chew apart most mythos monsters.

 

Minimum Damage: Of all the common defenses, this is the one where automatic weapons most shine.   At 1-3 damage per bullet, with high cyclic rates and enough guns you can kill monsters that otherwise shrug off weapons.  The only comparable strategy is shot gun slugs, which in the RAW have a minimum damage of 7 per hit.

 

Byakhee versus a Tommy gun is no contest.  It's going to die.   It simply can't shrug off the sort of damage that an automatic weapon (or semi-automatic shotgun) is capable of producing.   There are actually only a rather small number of mythos monsters for which firearms are ineffective, and most of those are simply immune. 



#39 Travern

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Posted 12 December 2017 - 05:29 PM

At close ranges, the Thompson at full-auto is apparently surprisingly controllable (link), thanks to it's heavy weight: it doesn't seem to climb very much at all.  (Of course, it's fair enough to wonder whether the effective ranges in this video, about ten or so paces, I suppose, are practical Call of Cthulhu ranges:  how many Call of Cthulhu nasties would you want to stand that close to?)

 

In addition to the range issues in the video you point out, the shooter sticks with controlled bursts rather than emptying the magazine.

 

By the way, the Thompson with a drum magazine had a surprising amount of torque, I've been told by someone who fired the WWII model.



#40 jlynn

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Posted 12 December 2017 - 06:50 PM

@Celebrim:  No need to get testy.  The fact of the matter is that I served as an infantryman and in combat, and I have to tell you all these assumptions about aimed fire or standing around and shooting from the hip just don't really pan out the way civilians think they do.  Frankly, your most "attended to" issue in a firefight is maintaining cover while simultaneously not getting pinned down; anyone who tells you different wasn't there.  Sure, a stone-cold veteran or killer might try these things, but almost invariably, the only people that are going to do them are the ones who have decided they are already dead and just haven't gotten hit yet, or someone that simply flips out under the stress.

 

So maybe someone confronted with a Cthulhu-style horror might fit one of those latter categories, especially if no one is shooting back (e.g., a Byakhee doesn't use a Tommy Gun); but frankly, even World War I or World War II veterans are going to go with what worked for them under fire previously if they are being shot at by cultists or someone.  They'll seek the best possible cover and concealment, they'll move to avoid being pinned down, and they will "spray" automatic weapons fire towards the enemy in order to facilitate those things.  And yeah, sure, they'll use aimed fire when they can get a good position -- which is when the vast majority of the casualties will be inflicted.  It's why we use covering fire with one section, while another section is maneuvering, but even then the goal isn't primarily to inflict casualties, but rather to force the enemy to keep their heads down, and not permitting them to undertake aimed fire of their own against the maneuvering section.

 

"I disagree that automatic weapons are simply spray and pray weapons."  Okay, and I think you're wrong, based on combat experience.  But you're certainly entitled to your opinion on the matter, and I won't denigrate you, or your opinion.

 

Also, I note that "the combat round" as defined in the 7th Edition rules is a "deliberately elastic period of time designed to permit each player to conduct a single action."  Which means that depending on the actions taken by each player it could be anywhere from one to five seconds or maybe even ten seconds in rare cases of complex "single actions."  The fact of the matter is that you don't know how long it is, other than it probably isn't 30 seconds in length.  During five or ten seconds, you could indeed put 50 to 100 rounds down-range.  In short, trying to rigidly define it isn't really all that great a justification for anything.

 

"The idea that automatic weapons are primarily "psychological" weapons is absurd.  During WWI a great many very brave men charged across open ground quite fearlessly, and were cut to pieces by automatic weapon fire regardless of how stoically they braved the balls." 

 

Fun fact, during World Wars I and II, it required over 100,000 rounds of small arms fire to inflict a single casualty ( Col Trevor N. Dupuy, Numbers, Prediction, and War).  So tell me again how that's "absurd?"  Putting a division into open ground covered by enemy machine guns and charging standing up is what the Germans call a "Himmelsfahrkommando" -- a command which guarantees a ride to heaven.  I might also add, that trying to cross barbed wire with thousands of men over an open field (even with lots of shell holes) in the face of a hundred or so machine guns and under constant artillery fire will virtually ensure the command gets "cut to pieces."  Crossing that same area using cover and concealment, while low-crawling, conversely, doesn't.  Tactics make all the difference in the world.  Automatic fire suppresses the enemy because they FEAR getting cut apart.  And, if they charge standing up in a line, they almost certainly will; but in actual combat, it's the psychology of all that lead flying around that might hit you that has the effect, not the actual lead.  And, referring back to Colonel Dupuy, even during Vietnam, where arguably there was a LOT more full automatic fire than during World War I (everyone carried his own machinegun in Vietnam, in effect), it still took 50,000 rounds of small arms fire to inflict a single casualty.

 

Another fun fact:  Are you aware that tracer ammunition has a significantly different trajectory than the normal ammunition it is usually belted with?  That, in fact, trying to adjust your fire based on the impact of the tracers actually only ensures that one of every five, ten or fifteen rounds (depending on the frequency of the tracer ammunition in the belt) hits the target, while the remaining 80% plus of your rounds actually miss the target area?  Recent trajectory testing thus reveals that putting in tracer ammunition actually increases the enemy's chance of survival!  Unfortunately, no one knew this up until about two years ago when the testing confirmed it, but several aces in World War II and Korea remarked that they felt something was wrong with the tracers and that they instead used their gun sights and didn't worry about where the tracers were going.

 

Finally, since no one has actually tested firing a Vickers machine gun into a Lesser God, I think I'd hesitate to declare it factually the case that a "Vickers machine gun will kill a Lesser Outer God". In game terms, maybe the rules would indicate that; but since RPG rules do not necessarily reflect reality, what you're really saying is that the rules author thinks that might be the case.  And someone with different assumptions might disagree, theoretically speaking.  Not that it's terribly important either way; but the point is that everyone approaches this GAME differently, and with different views on what the "reality" of Mythos creatures might be.  So perhaps we shouldn't "lay down the law" too much unless we first explain what our biases in the matter are.