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Old 04-19-2019, 10:21 PM   #21
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Default Re: Iron Content of Rifle Ammo

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Originally Posted by Icelander View Post
Ah, indeed. I suppose that happens, as 7.62x54R rounds are used for the same purpose.

Swaging it down sounds great.
Unless your rifles already have tight bores, using .310" bullets in rifles intended for .310" bullets won't matter too much. Rifles intended for .308 have a nominal .300 bore (measured from land to land), so 2/1000ths of an inch extra won't be excessive in a modern weapon as long as the round isn't a really hot one.
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Old 04-20-2019, 11:14 AM   #22
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Default Re: Iron Content of Rifle Ammo (SS109/M855, M59, M61, M80, M855A1, etc.)

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I suspect they'd order metal of the grade they needed and use extrusion (that's how things like nuts are made), but does it really matter? There's no question that soft iron bullets can be manufactured.
Well, I guess it might not matter.

I just like to have a general sense whether such iron lead-free rounds would be notably more difficult to make, more expensive or less effective than lead-free ammunition which is manufactured in the real world. I imagine that the fact you couldn't import such rounds into the US and sell on the commercial market* has a lot to do with why no real companies manufacture such lead-free rounds, but it might also be that there is some technical reason why copper, tungsten/polymer composites and numerous other alternatives are made instead of iron/mild steel lead-free rounds.

Basically, I'm trying to determine whether any ammunition manufacturer in my setting can justify using iron/mild steel to make lead-free rounds without being aware of the supernatural and the role of such rounds for monster hunting. Could, say, the Swiss Army adopt an iron round as their target ammo, even if most of their officers and staff know nothing of the supernatural, but merely for environmental reasons?

I'll grant that the copper slug, reversed copper jacket and hardened steel penetrator of the M855A1 and M80A1 rounds that the US armed forces adopted for environmental reasons are probably more effective than equivalent iron/mild steel rounds that I'm my proposing that RUAG, Fiocchi and CBC manufacture in the alternate reality of my setting. But for armies like the Italian and Swiss, for example, slightly inferior terminal effects might not outweigh concerns of cost and environmental impact.

So, are iron/mild steel rounds potentially cheaper to make than the advanced lead-free alternatives that use copper, tungsten or other more exotic materials? Or is the iron/mild steel so much more difficult to work that it more than wipes out any gains from lower material costs?

In game terms, is it always a clue for the PCs that an organization is controlled entirely by a faction aware of the supernatural if they purchase or otherwise acquire iron/mild steel ammunition, or could they just be selecting a competatively priced alternative to the US-made M855A1, M80A1 or any foreign equivalents of such advanced lead-free ammo?

*Because it would be legally defined as 'armor-piercing pistol ammunition', even though it is probably no better at penetration than pure copper rounds (and that 5.56x45mm and 7.62x51mm are obviously not pistol rounds, but the existence of stockless firearms in those calibers legally nakes them that according to the ATF).
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Old 04-20-2019, 11:26 AM   #23
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Default Re: Iron Content of Rifle Ammo (SS109/M855, M59, M61, M80, M855A1, etc.)

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They'd cold-forge it for bar or rod stock of 1cm or 1/2" or so 'diameter', or possibly from a flat strip that they cut bullet sized bits off.
There is a delicious irony to the possibility that the Vatican-backed monster hunters might thus really field 'cold-forged iron' weapons, for purely practical reasons of manufacturing, not because the iron needs to be 'cold-forged' to have its mystical effects.

Although I would certainly round in the favour of more mystical effectiveness for such poetic allusions in armaments, if it came up.
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Old 04-20-2019, 11:55 AM   #24
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Default Re: Iron Content of Rifle Ammo (SS109/M855, M59, M61, M80, M855A1, etc.)

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Originally Posted by Icelander View Post
Basically, I'm trying to determine whether any ammunition manufacturer in my setting can justify using iron/mild steel to make lead-free rounds without being aware of the supernatural and the role of such rounds for monster hunting.
This is fairly unlikely. The high-purity soft iron you need for such rounds is probably fairly expensive, and certainly corrodes easily. There's also no easy way* to make it match the weight of the conventional bullets that weapons are sighted for. That will make a difference at ranges that are relevant to snipers and machine gunners, and armies don't like to have weapon-specific ammunition, or different weapons for training and combat**.

If you were to use iron rounds at long ranges, you would need to re-calibrate the sights; it's only at the short ranges typical of monster-hunting combat that the difference would be insignificant.

*You could match density by using iron rounds with tungsten inserts, but pressing inserts into soft iron is much more difficult than pressing them into lead.
*If a soldier has a gun that is his, he can be persuaded to look after it. Guns that are only used for training don't get cared for so well, and training with inaccurate and unreliable weapons is bad for soldiers' confidence.
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Old 04-20-2019, 12:44 PM   #25
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Default Re: Iron Content of Rifle Ammo

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Unless your rifles already have tight bores, using .310" bullets in rifles intended for .310" bullets won't matter too much. Rifles intended for .308 have a nominal .300 bore (measured from land to land), so 2/1000ths of an inch extra won't be excessive in a modern weapon as long as the round isn't a really hot one.
Well, the 7.62x51mm steel-core rounds would have been mostly intended for licensed copies of FAL rifles made by IMBEL, and converted to the ParaFAL standard by the same company, with 436mm, 440mm or 450mm barrels in 1:12 inch twist rate, as well as ArmaLite AR10A4 rifles with 16-inch chrome-lined barrels with 1:11.25 inch twist rate.

The production round that CBC eventually makes should function in any IMBEL-made FAL and the AR10A4 rifles, as well as functioning in the HK417 rifles that the Brazilian Army Special Operations Command owns (though I don't know which barrel length they got, only that they were bought prior to the A2 models in 13",16.5" and 20" barrel length replacing the original 12", 16" and 20" barrel models). Presumably occult-aware armourers in the Army ensured that some of the handloads made before they convinced CBC of making commercial mild steel ammo worked for the HK417 rifles as well.

I don't know if any of these rifles have notably tight bores or if the same handloads would work for all of them. There are also the 7.62x51mm chambered FN Minimi ('Maximi') machine guns to consider, as they appear to be fielded by some of the military and police special units in Brazil that are likely to have fought monsters.
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Old 04-20-2019, 02:56 PM   #26
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Default Re: Iron Content of Rifle Ammo (SS109/M855, M59, M61, M80, M855A1, etc.)

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I think that you need some softness in a bullet somewhere, so that it can accommodate to the rifling. The classic copper-jacketed lead has no problem, of course. All-copper bullets are OK, as is steel core, lead layer and steel jacket (the copper wash on those is to prevent corrosion).

Sintered iron is OK at pistol velocities, but needs a jacket of some kind at rifle velocities, and manufacturing that gets interesting.

Jacketed lead bullets are made by drawing the jacket and packing lead wire in under hydraulic pressure. I think steel-core bullets are made by partially packing the jacket with lead wire and then ramming in the steel core under higher hydraulic pressure, so that the lead flows.

To make an all-iron bullet, you could draw a steel jacket, that's straightforward. Then you could pack that with powdered iron, but to sinter that, you need to heat the whole thing red-hot under high pressure, without the jacket warping. That's an industrial process, not a job to do on an armoury bench.

The best method for a high-iron bullet may be a one-piece bullet made from an iron alloy that is ductile enough to deform to rifling. It will still need a copper or nickel wash, or it will corrode really fast. I'll do a bit of research.
Thanks for the research.

Given that a few visionary indivuduals started to become aware of the paranormal and that by the 2000s, there had emerged numerous formal (but mostly informal) groups of people who recognized the supernatural as a terrible threat on a worldwide scale, it's likely that bullets designed to deliver mystically significant materials have been produced in small lots for 15-20 years. Silver bulllets, hollow-points with various esoteric substances, shells firing wooden stakes, etc. Probably most practically effective and definitely the most common, steel bullets.

Granted, there was not nearly as much need for anti-supernatural weapons in the early 2000s (when supernatural influence was rarely overtly visible and even when present, rarely could be engaged kinetically) as there is in the 2010s (near or in Vile Vortices, ley line confluences or Places of Power, actual monsters that are difficult to stop with conventional weapons might hunt).

Still, small teams of Catholic military men, Swiss Guards and the Knights of Malta, backed by the Vatican, have at least 15* years of experience at fighting the supernatural, the British Rangers serving the 'Shadow Court' of Queen Elizabeth II have about the same amount of experience and various other groups that have sprung up around areas of high supernatural threat levels might have similarly long histories. The Brazilians have certainly been fighting a war with supernatural forces since the early 2000s, although it might have taken years before any of the soldiers or policemen engaged encountered something other than humans influenced toward violence and madness by various spirits and entities.

There are twelve Vile Vortices around the world and many magical hot spots where the mana levels are higher than elsewhere, which means that there will be tbose in almist every nation who have become aware of the supernatural, even though most governments officially do not admit its existence, so it's guaranteed that there are other secretive groups aware of the supernatural than those PCs know about. Indeed, for large parts of the workd, I haven't even thought about who might know about the supernatural and what they are doing about it.

All of which is to say that there have probably been numerous attempts by secret groups to influence ammunition manufacturers to make rounds useful for self-defence from supernatural threats as well as monster hunting.

It's likely that different armourers, custom ammunition manufacurers and those few actual arms companies that have undertaken to make mystically useful ammo have tried different methods. I expect several different groups use sintered iron pistol-caliber rounds, for example, and obviously there are a great number of 7.62x39mm and 7.62x54R rounds made for armies across the world that already are effective against anything vulnerable to iron weapons.

As for other rifle calibers, I expect that there will be multiple variations. Some will rely on loading steel-core bullets made for Russian or Chinese military rifles in other .30 caliber rounds, either with or without swaging. Others will make similar steel-core bullets from scratch, using whatever grade of mild steel comes out the cheapest and trying several variations of jacketing to avoid damage to barrels and ensure the rifling works. Yet others will simply adopt a hardened steel AP round as their standard monster-hunting ammo.

The monolithic pure iron bullet is an elegant alternative, especially if it can be coated in a thin protective layer of something soft that gives resistance to corrosion and reduces barrel erosion. Perhaps it might even be possible to give an advanced version of such a bullet a hardened steel penetrator, as is done with the copper M855A1 and M80A1 rounds.

Some manufacturers influenced by occult-aware groups might even try a frangible iron or steel round, jacketed sintered iron or prefragmented steel. Fiocchi makes some kind of frangible SJPRN rounds, which I believe are Semi-Jacketed Polymer Round Nose and could be lead-free. It might be possible to use polymer or other advanced materials to encase an iron or steel payload designed to fragment or expand in a different version of such bullets.

*The Holy See has studied the paranormal for longer than this, at least thirty years, and individual Catholics might have had violent encounters with supernatural entities in the 1980s and certainly by the 1990s, but Kessler, the PCs' Patron, believes that the incresed secret acticity by agents of the Vatican in 1999-2004, merely represented a more organized defensive strategy to supplement its research into the supernatural. Not until the election of Pope Benedict XVI in 2005 did the Vatican start to send out armed teams to strike at specific threats, with explicit orders to kill or capture.
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Old 04-20-2019, 03:48 PM   #27
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Default Re: Iron Content of Rifle Ammo (SS109/M855, M59, M61, M80, M855A1, etc.)

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Originally Posted by Icelander View Post
The monolithic pure iron bullet is an elegant alternative, especially if it can be coated in a thin protective layer of something soft that gives resistance to corrosion and reduces barrel erosion.
The usual method of reducing corrosion of iron is to coat it in zinc. I have no idea what a zinc jacket would do to a rifled barrel, however. It seems to be a little bit softer than copper, so it might work well. Or, it might scrape off an foul your barrel*.

A high tech anti-corrosion method that was discovered in the last few years is to coat the iron or steel in a thin layer of graphene. Unfortunately, these days graphene is still mostly a laboratory curiosity - while it is available commercially, what is available is typically very low quality (and often contains no actual graphene).

You might want to think about what it is about the iron that has such an effect. If it is any physical property - chemistry or ferromagnetism, say - there will be ways to alloy or otherwise enhance the iron to make it more effective. This in itself could lead to an adventure. The boffins want to figure out why iron works so well, so they send the PCs out to collect a statistically significant sample of supernatural critters for destructive testing at the lab. Can the right catalyst make bullets more effective, or using neodymium iron boride? what particular alloy of transition group metals has the greatest supernatural punch. By the rules of narrative logic, things will invariably go wrong leading to even more excitement with PCs and monsters stalking each other through laboratory buildings at night amongst nasty chemicals, fume hoods, high voltage machinery, and other fun stuff (see the recent GURPS Action 5: Dictionary of Danger)..

Luke

* I had the experience of going shooting one day with my .22 caliber rifle an a box of lead bullets. At the beginning, I was knocking down targets right and left. One of the guys at the range called me a "dead-eye". Then, my accuracy started getting worse and worse. I put it down to fatigue, but toward the end of the day i could barely hit anything. When I got home and started cleaning my gun, I found out why. The lead from the bullets was stripping off and plating the inside of my rifle's barrel. What had started out as a .22 rifle ended up being something like a .20 smoothbore. Anymore, I only shoot jacketed bullets.
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Old 04-20-2019, 05:06 PM   #28
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Default Re: Iron Content of Rifle Ammo (SS109/M855, M59, M61, M80, M855A1, etc.)

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This is fairly unlikely. The high-purity soft iron you need for such rounds is probably fairly expensive, and certainly corrodes easily. There's also no easy way* to make it match the weight of the conventional bullets that weapons are sighted for. That will make a difference at ranges that are relevant to snipers and machine gunners, and armies don't like to have weapon-specific ammunition, or different weapons for training and combat**.

If you were to use iron rounds at long ranges, you would need to re-calibrate the sights; it's only at the short ranges typical of monster-hunting combat that the difference would be insignificant.

*You could match density by using iron rounds with tungsten inserts, but pressing inserts into soft iron is much more difficult than pressing them into lead.
*If a soldier has a gun that is his, he can be persuaded to look after it. Guns that are only used for training don't get cared for so well, and training with inaccurate and unreliable weapons is bad for soldiers' confidence.
Those are good points.

There is also the fact that the tombac-jacketed lead core GP90 round that the Swiss Army currently issues would be mass-produced Match ammo in GURPS terms and the Swiss have a long tradition of individual marksmanship. The GP90 round is actually designed to reduce lead emissions, as the militia service for Swiss men requires massive amounts of ammo to be expended at their ranges every year, and the Swiss are fairly environmentally conscious. While a lead-free bullet might thus actually be considered there, there would, however, probably be public outcry if any proposed new round could not deliver the level of accuracy demanded in the Swiss service round.

What sounds much more likely is that organizations that do not use SAWs or machine guns in the same caliber as an infantry rifle (or at all) and have no reasonable need for long range performance might adopt iron/mild steel lead-free ammunition for environmental reasons, at least if the external and terminal ballistics are adequate at typical engagement ranges and the cost is reasonable. Such organizations could include the Pontifical Swiss Guard, police departments or security contractors.
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Old 04-20-2019, 06:34 PM   #29
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Default Re: Iron Content of Rifle Ammo (SS109/M855, M59, M61, M80, M855A1, etc.)

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The usual method of reducing corrosion of iron is to coat it in zinc. I have no idea what a zinc jacket would do to a rifled barrel, however. It seems to be a little bit softer than copper, so it might work well. Or, it might scrape off an foul your barrel*
A lot of budget ammo from Russia and elsewhere is zinc-coated or has zinc-washed steel jackets. There are a lot of passionate opinions on the subject, but a quick review of random forum arguments seems to suggest that it makes cleaning slightly more bothersome and might increase barrel wear, but it certainly wouldn't ruin a modern rifle within a typical adventure and it probably won't make much of a difference to any shooter who regularly cleans his weapon.

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A high tech anti-corrosion method that was discovered in the last few years is to coat the iron or steel in a thin layer of graphene. Unfortunately, these days graphene is still mostly a laboratory curiosity - while it is available commercially, what is available is typically very low quality (and often contains no actual graphene).
What about polymer or composites?

From what I can tell, ammunition manufacturers sometimes experiment with exotic materials. Ideally, for the pure iron slug, we want as little as possible of the final product being anything other than iron, for mystical effects, but we also want to avoid ruining barrels or the ammo being impossible to store.

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Originally Posted by lwcamp View Post
You might want to think about what it is about the iron that has such an effect. If it is any physical property - chemistry or ferromagnetism, say - there will be ways to alloy or otherwise enhance the iron to make it more effective. This in itself could lead to an adventure. The boffins want to figure out why iron works so well, so they send the PCs out to collect a statistically significant sample of supernatural critters for destructive testing at the lab. Can the right catalyst make bullets more effective, or using neodymium iron boride? what particular alloy of transition group metals has the greatest supernatural punch. By the rules of narrative logic, things will invariably go wrong leading to even more excitement with PCs and monsters stalking each other through laboratory buildings at night amongst nasty chemicals, fume hoods, high voltage machinery, and other fun stuff (see the recent GURPS Action 5: Dictionary of Danger)..

Luke
That sounds good.

The Fair Folk and other fey are supposedly powerfully affected by iron (fey creatures are fairly common, as supernatural monsters go, but as far as the PCs knkw, no one living today has demonstratably spoken with one of the Fair Folk themselves, though rumours abound). According to what old lore the PCs consider credible, there is no iron in Faerie and the metal repels the fey, shorts out their glamour and seems to play havoc with their senses. It's also extremely toxic to most fey creatures, to the point that the Dr. Lapointe, the occult librarian who works with the PCs classifies supernatural beings as 'fey' or not according to whether they can tolerate iron.

Iron also affects some kinds of spirits negatively. Manifested spirits, i.e. spirits who have somehow embodied a physical body through metaphysical means, are especially prone to being vulnerable to iron, though in such cases, the iron is not toxic to them in the same way as fey creatures, but rather bypasses some of the magical protections such paranormal flesh has.

Often, specific spirits or other supernatural entities may be even more vulnerable to different substances or conditions, i.e. precious metals like copper, gold or silver, various types of wood, herbs or other plants, minerals like jade or flint, sunlight, running water or a wide variety of other things, but most of these are harder to make weapons from than iron and steel.

Iron is regarded as difficult to affect with magic, although not impossible, and even magic or curses that are not of fey origin may sometimes be grounded or resisted by grasping iron. Salt and ash, however, are regarded as even more effacious anti-magic substances than iron and most counter-curses or spirit-cleansing involves either or both. Rusted iron is sometimes seen as even more magically inert than ordinary iron, which is desirable for many protective uses.

In general, iron is broadly useful for countering the supernatural and harming monsters, but is not the sovereign remedy for any curse or the biggest weakness for any monster, except those of fey origin. Against anything fey, iron is a panacea.

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* I had the experience of going shooting one day with my .22 caliber rifle an a box of lead bullets. At the beginning, I was knocking down targets right and left. One of the guys at the range called me a "dead-eye". Then, my accuracy started getting worse and worse. I put it down to fatigue, but toward the end of the day i could barely hit anything. When I got home and started cleaning my gun, I found out why. The lead from the bullets was stripping off and plating the inside of my rifle's barrel. What had started out as a .22 rifle ended up being something like a .20 smoothbore. Anymore, I only shoot jacketed bullets.
Yeah, we definitely want to avoid this.
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Old 04-20-2019, 08:39 PM   #30
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Default Re: Iron Content of Rifle Ammo (SS109/M855, M59, M61, M80, M855A1, etc.)

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What about polymer or composites?
if you can chemically and electrically isolate the iron from the environment, this should work. The main issue is that if you have any hole in the coating you can get an electrical connection and the iron can start donating electrons to other things. This leads to corrosion, which is generally considered bad. The main solution is to pair the iron up with something that is even more happy to donate electrons than the iron is, as a sacrificial electrode. Hence, zinc.

I'm not really sure how the graphene gets around this, just that some laboratory results showed increased corrosion resistance.

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