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BulletGeek
11-14-2008, 11:45 AM
I was wondering... could one wrap a swaging core in three or four wraps of aluminum foil, then swage it to shape and not tear the foil?

If it worked, the result would be a very soft bullet with just enough jacket to prevent leading.

Tom Herman
11-14-2008, 12:34 PM
Aluminum only exists as a metal because it is covered by a thin layer of Aluminum Oxide (Al2O3).
Although what you described sounds all nice and wonderful, every time you would fire one of these bullets (if it even works), you're scrubbing your bore with what is essentially sapphire particles (hardness 9 on the Mohs scale, just under diamond).
I try not to fire anything harder than alloyed lead through any of my bores!
And you will also have a mechanical stability issue with the foil: I would expect it to break and slough off everywhere from the chamber onward.
I could easily see foil particles clogging things up and having unfortunate safety issues as a result.

Happy Shootin'! -Tom

BulletGeek
11-14-2008, 01:25 PM
So you don't know either? :D

Mygila
11-14-2008, 03:47 PM
Bullet Geek, Tom is correct. I sold al/oxide abrasives for years. In the beginning of the micro chip revolution I sold thousands of pounds to chip makers for lapping wafers. This is a bad ides. Mygila

BulletGeek
11-14-2008, 04:49 PM
I understand that you both firmly believe that I should not shoot aluminum bullet surfaces through my guns, and I appreciate that you're looking out for my best interest. I believe you both.

But I do not swage bullets myself, and probably never will, so it's an entirely academic question...

...which nobody has as yet answered for me.

I would still like to know the answer, if anyone happens to know. Please.

Thanks in advance.

deltaenterprizes
11-14-2008, 05:12 PM
It would be like paper patching, but you could call it "aluminum patching". I have heard about people wraping bullets with teflon tape also. I think Winchester "Silvertip" pistol bullets are/were made out of aluminum.
As stated above I would rather clean lead from the bore than change barrels!

BulletGeek
11-14-2008, 05:14 PM
As stated above I would rather clean lead from the bore than change barrels!

As would I.

BulletGeek
11-14-2008, 06:16 PM
Question for Tom:

Knowing that a film of aluminum oxide coats the surface of aluminum foil, what would you suppose the grit size of that Al203 to be?

Ricochet
11-14-2008, 09:34 PM
BulletGeek, I thought of what you're contemplating when I was about 10 years old. Never have had any bullet swaging equipment. If you try it, let me know how it works.

jhalcott
11-15-2008, 01:22 AM
Those "SIVER TIPS" never touched the bore as they went down the tube. Geek, take your favorite ALUMINUM cleaning rod and drag it against the crown of your best gun a few hundred times. Then uses a jewelers loupe to examine the results. I would hesitate to use CERTAIN papers to patch my bullets also. Some paper is made with a chalky clay that is very abrasive. The simple answer to your querry is NO.! The wraps would not hold up to the stress. A TUBE of aluminum filled with a lead core should hold up BUT would abrade the bore very quickly. There is a "sabot" round for the Abrams tank that has an aluminum sabot with a titanium penetrator (28 pounds@5000+fps) that is used sparingly. They are not allowed to use many of these before there is bore damage. The sabot is made from a special aluminum alloy.

BulletGeek
11-15-2008, 09:44 AM
Geek, take your favorite ALUMINUM cleaning rod and drag it against the crown of your best gun a few hundred times. Then uses a jewelers loupe to examine the results. I would hesitate to use CERTAIN papers to patch my bullets also. Some paper is made with a chalky clay that is very abrasive. The simple answer to your querry is NO.!

Dang, I'm not sure what I did to encite such vehemence. After learning of the potentially abrasive properties of aluminum in a firearm's bore, it occurred to me that it might make a good method of fire-lapping a bore. The clay-coat paper (from your better magazines, for example) might also work in that regard too.

Please, folks, don't light into me. It's just a discussion after all.

looseprojectile
11-15-2008, 12:05 PM
Don't feel bad. I have thought of using soft steel for the same thing.
I have not had swaging equipment to do this also.
A few might not hurt the bore a lot?
All a steer can do is try.:coffee:.
Life is good

BulletGeek
11-15-2008, 01:39 PM
Combloc countries have used bullets with jackets of mild steel. It works. Barrel life is somewhat diminished, though exactly how much I don't know.

unclebill
11-15-2008, 03:02 PM
i never knew aluminum is almost as hard as diamonds .
learn something every day.
even if it only the outside that is that hard.
if it cant exist without the hard part .
then it's as hard as a Sapphire.
at least for what it would theoretically be used for here.

unclebill
11-15-2008, 03:03 PM
BulletGeek, I thought of what you're contemplating when I was about 10 years old. Never have had any bullet swaging equipment. If you try it, let me know how it works.

i probably couldnt SPELL bullet when i was 10!:mrgreen:

waydownsouth
11-15-2008, 03:51 PM
will some one with a swaging press please give it a go and post a few photos just to see if it can be done. there can be no harm done just by experimenting with the idea and we may all learn something in the process

no im not asking you to shoot em, just swage one up for the camera. a couple of wraps of foil should only take a few extra seconds

my guess is the foil will tear when swaged but even if it didnt when fired would leave a ribbon of foil some where down range which would probably effect accuracy

powderburnerr
11-15-2008, 06:38 PM
I am not sure I want it in my dies either ,,, I see it tearing as it is bumpd up......Dean

JSnover
11-15-2008, 08:44 PM
I think some copper or brass foil or shim stock might be a better idea but I doubt the jacket would behave after the bullet left the barrel.

jhalcott
11-15-2008, 08:53 PM
Did the early Whitworth rifle use mild steel or iron bullets for some really long range shooting? I heard a story about this a LONG time ago. The bullets(billets?) were supposedly cast with the barrel twist in the mold.

JSnover
11-15-2008, 08:57 PM
Don't know about iron or steel bullets but I think there was a hexagan shaped bullet made for a Whitworth (I think it was a whitworth) rifle with a hexagonal bore

Jim
11-15-2008, 10:22 PM
If you doubt the abrasiveness of alum. foil, try the old Boy Scout trick of cleaning the grill with it. Wad up a fair sized sheet and srub the top of your BBQ grill. In a New York minute, it'll clean the grill down to new metal. You can actually FEEL the scrubbing going on.

Tom Herman
11-15-2008, 11:02 PM
Hi Bullet geek!

No ill feelings intended! I just wanted to male the case that Aluminum foil jackets are probably not a good idea.
One other thing: because the foil is thin, it would tend to disintegrate. If you had a thicker jacket, you might have more success at keeping it intact.
Again, using Aluminum as a jacketing material isn't good.
Like a lot of us, I don't have any swaging equipment, so I can't tell you how easy it would be to squeeze lead into foil...

Happy Shootin'! -Tom






Dang, I'm not sure what I did to encite such vehemence. After learning of the potentially abrasive properties of aluminum in a firearm's bore, it occurred to me that it might make a good method of fire-lapping a bore. The clay-coat paper (from your better magazines, for example) might also work in that regard too.

Please, folks, don't light into me. It's just a discussion after all.

woodsoup
12-06-2008, 01:27 PM
How many here use aluminum gas checks? Or shoot oxidized copper jacketed boolets? Who has never dropped a round, picked it up and wiped it off on his pants and then stuffed it into his breach?

The boyscout trick works because you wad up the foil and that produces many angles to dig into the grunge on the grate.

Any oxide on aluminum foil will not be of sufficient grit size to harm anything in a steel gun barrel. Go ahead, sharpen your pocket knife on a sheet.

Southron Sanders
12-06-2008, 03:37 PM
Whitworth rfle bullets were made out of hard LEAD. "Bolts" (bullets) for Whitworth CANNON were made out cast iron.

The Confederacy imported a a dozen or so Whitworth cannon. Several were used in the Battle of Gettysburg in 1863.

unclebill
12-06-2008, 04:05 PM
How many here use aluminum gas checks? Or shoot oxidized copper jacketed boolets? Who has never dropped a round, picked it up and wiped it off on his pants and then stuffed it into his breach?

The boyscout trick works because you wad up the foil and that produces many angles to dig into the grunge on the grate.

Any oxide on aluminum foil will not be of sufficient grit size to harm anything in a steel gun barrel. Go ahead, sharpen your pocket knife on a sheet.

THAT makes sense to me.

ra_balke
12-06-2008, 07:43 PM
Just for fun, you might try teflon tape.

I read somewhere a long time ago, about a guy who used teflon tape to " paper patch" his bullets, and he reported that it worked fine.

I have never tried it.

Ricochet
12-06-2008, 10:06 PM
I think I've posted this on here before, but if anyone encounters aluminum fouling in his bore, a patch wet with either lye or sodium carbonate will take it right out.

jhalcott
12-07-2008, 12:39 AM
YES , Teflon tape does work quite well! It IS tedious to get it wrapped on though.

Lead pot
12-07-2008, 05:17 PM
I been swaging for going on 40 years and that brain fart thought never entered my mind.
First the wraped jacket would not stay on the bullet at the high RPM it spins.
A .22 rim fire case that is a solid cylinder or cup will blow off at 3200 fps+
But you can use aluminum for a core in a guilded jacket.

NoDakJak
12-07-2008, 06:34 PM
I have also used the teflon thread tape. It worked very well in some applications and not so well in others. I definetly intend to keep experimenting with it. Neil

BulletGeek
12-08-2008, 06:47 PM
First the wraped jacket would not stay on the bullet at the high RPM it spins.
A .22 rim fire case that is a solid cylinder or cup will blow off at 3200 fps+


Well, I confess I can't see what difference it would make if it did come off in flight. Once it's out the muzzle, its job would be done.

Lead pot
12-08-2008, 09:01 PM
Well, I confess I can't see what difference it would make if it did come off in flight. Once it's out the muzzle, its job would be done.

Well evidently you have never shot a soft jacketed bullet like a Hornady SX at over 3200 and seen a smoke trail that wont reach 50 yards and never put a hole in the paper at 100 yards.
If the jacket wont hold the the lead core will not survive the high rpm of a 14 twist

wills
12-08-2008, 11:18 PM
Save the aluminum foil to use for hats.

docone31
12-09-2008, 12:38 AM
http://zapatopi.net/afdb/
Might come in handy one day.
http://zapatopi.net/blackhelicopters/
Of course, there is always the clear and present threats.
Tinfoil is good for you.

klcarroll
12-09-2008, 11:49 AM
Well, …..Maybe the grain size of naturally occurring aluminum oxide isn’t large enough to cause visible scoring; …….But an aluminum oxide surface certainly lacks the natural lubricity of copper or even a leaded steel.

……And isn’t being “kind” to our bores one of the major reasons we are casting nice lead boolits????

KLC

oldoak2000
01-27-2009, 05:23 PM
aluminum oxide = SANDPAPER! . . . (regardless of the grit) . . . .

(ie, sandpaper is made using aluminum oxide) . . . a bad idea unless you intend to lap / grind the bore . . . . . . .

sail32
01-27-2009, 08:53 PM
A billet is a lump of iorn or steel, that is used to make an object, like a barrel.
You may wish to research the use of aluminum. I seem to remember the US Navy had added aluminum to its 16 inch gun powder. I cannot remember if it was to increase barrel life or range. I would suspect it would have an effect on pressure.

357maximum
01-28-2009, 12:39 AM
A billet is a lump of iorn or steel, that is used to make an object, like a barrel.
You may wish to research the use of aluminum. I seem to remember the US Navy had added aluminum to its 16 inch gun powder. I cannot remember if it was to increase barrel life or range. I would suspect it would have an effect on pressure.

Aluminum (german milled) is used in flash powder(firecracker/m-80), mixed with perchlorates and other goodies. Could the aluminum added to the 16inch shell be an additional fuel source for the powder? more range from more ooomf?

Slowpoke
01-28-2009, 01:47 AM
That would be my guess.

Back in the 80's the copper mines in S AZ used powdered aluminum for most of their open pit blasting .

good luck

captainkirk
02-02-2009, 04:04 PM
How many here use aluminum gas checks? Or shoot oxidized copper jacketed boolets? Who has never dropped a round, picked it up and wiped it off on his pants and then stuffed it into his breach?

The boyscout trick works because you wad up the foil and that produces many angles to dig into the grunge on the grate.

Any oxide on aluminum foil will not be of sufficient grit size to harm anything in a steel gun barrel. Go ahead, sharpen your pocket knife on a sheet.

Regardless of the "angles" presented by the foil, unless its surface is harder than the grit (and the grill) it will not cut into it.

woodsoup
02-02-2009, 05:18 PM
Kinda like cleaving a diamond with a steal chisel and a wooden mallet. I suppose folks can't do that either.

captainkirk
02-02-2009, 06:24 PM
There is a difference in Fracturing and Scratching. A harder substance may be fractured by a softer substance (think of a 1 meter long diamond "bat" hit by a steel ball). It will fracture, but it cannot be scratched - big difference.

hi-tek tm man
04-19-2009, 10:02 AM
About 8 years ago I worked at a wall border plant and would sharpen my knife as Iwas making adjustments.Talk about razer sharp

13Echo
04-19-2009, 11:57 AM
Going back to the addition of metal to a cannon's powder charge. The metal was tin and was used to reduce bore fouling. This was first done, I believe, in the French 75 and there were gunpowders with added tin, like HiVel#2 that reduced the metal fouling of cupronickle jacketed bullets.

Jerry Liles

n.h.schmidt
04-19-2009, 01:02 PM
I'm going to throw this into the mix. Reynolds Wrap makes a aluminum foil with a non stick coating on one side. We have this and its something like a teflon coating. Man you can burn just about anything on it and it just slides off . Like a no stick frying pan. It is good up to normal cooking and frying heat so that would not be a problem. If this was wraped on the bullet slick side out maybe it could work . Little to no aluminum would touch the bore at all.
n.h.schmidt

7of7
04-19-2009, 01:15 PM
I'm going to throw this into the mix. Reynolds Wrap makes a aluminum foil with a non stick coating on one side. We have this and its something like a teflon coating. Man you can burn just about anything on it and it just slides off . Like a no stick frying pan. It is good up to normal cooking and frying heat so that would not be a problem. If this was wraped on the bullet slick side out maybe it could work . Little to no aluminum would touch the bore at all.
n.h.schmidt

The only thing I see is that the rifling would cut through the foil. When it departs the bore, the gas pressure would blow all the aluminum off the lead, and you'd have a shredded aluminum wrapped lead bullet flying. What effect would the aluminum shreds have on accuracy, would be unknown.

I think a core would be better than a jacket...

StarMetal
04-19-2009, 01:17 PM
The only thing I see is that the rifling would cut through the foil. When it departs the bore, the gas pressure would blow all the aluminum off the lead, and you'd have a shredded aluminum wrapped lead bullet flying. What effect would the aluminum shreds have on accuracy, would be unknown.

I think a core would be better than a jacket...

None....what effect does rain have on bullets fired through it?

Joe

n.h.schmidt
04-19-2009, 05:43 PM
I beleive you are right about the rifleing cutting the foil and the blast doing further mayhem. Just like a paper patched slug. It probably isn't worth doing as pp seems to provide the same expeted results.
n.h.schmidt

Echo
04-19-2009, 08:43 PM
Hmmm... My Hi-Power friends say that rain DOES have an effect on the bullets flight. They told me that a bullet will strike higher than normal when fired through a rain shower. Water lubricates the bullet? IDK - it's just what the told me, and I believe them...

Bad Water Bill
04-20-2009, 07:18 AM
It sounds to me that most if not all answers here have only repeated what they have read BUT not researched. In their infinite wisdom and knowledge has any one ever found the micron size of the oxide formed on alum foil?

Has any one EVER considered the micron size of the particles sucked INTO A BBL WHEN YOU EXTRACT A CARTRIDGE FROM THE CHAMBER?

Check the Knots scale and learn the difference between sapphires and diamonds depending WHERE the diamonds are mined. Yes there is a great difference in diamond hardness. Do not ask me how I know

Jim_Fleming
04-30-2009, 06:09 AM
Uncle Bill,

Aluminum itself isn't as hard as diamonds, it's the aluminum oxide coating that forms on the surface of aluminum itself that's nearly as hard as diamonds... i.e. it's very thin, perhaps as thin as .0001" that's about 1/25th the thickness of a human hair.

Aluminum oxide is the material that most grinding wheels that're sold are made of.

Take Care,




i never knew aluminum is almost as hard as diamonds .
learn something every day.
even if it only the outside that is that hard.
if it cant exist without the hard part .
then it's as hard as a Sapphire.
at least for what it would theoretically be used for here.

Dan Cash
04-30-2009, 09:53 AM
Those "SIVER TIPS" never touched the bore as they went down the tube. Geek, take your favorite ALUMINUM cleaning rod and drag it against the crown of your best gun a few hundred times. Then uses a jewelers loupe to examine the results. I would hesitate to use CERTAIN papers to patch my bullets also. Some paper is made with a chalky clay that is very abrasive. The simple answer to your querry is NO.! The wraps would not hold up to the stress. A TUBE of aluminum filled with a lead core should hold up BUT would abrade the bore very quickly. There is a "sabot" round for the Abrams tank that has an aluminum sabot with a titanium penetrator (28 pounds@5000+fps) that is used sparingly. They are not allowed to use many of these before there is bore damage. The sabot is made from a special aluminum alloy.

The SABOT round penetrator for the M256, 120 mm gun used on the Abrams tank, is depleted uranium, not titanium. big difference. You are correct that the SABOT itself is a special alloy of Aluminum that is harder than wood pecker lips and twice as tough. The SABOT itself is not in heavy contact with the chrome plated smooth bore. The gun is capable of 2500 rounds or so before condemnation. Wear is not soo much the problem as is the elastic peak of the barrel as the gun operates at upwards of 100 thousand PSI. When I left government service in 2005, the round count was being constantly increased as that gun is one stout piece of work and the chrome lining resists wear very well.

Bottom line, Aluminum alloy in a 120 mm tank round and aluminum jacketed bullets in my rifle barrel are not a good comparison as the functions are not the same.

jhalcott
04-30-2009, 02:41 PM
Just thinking about this Aluminum jac ket thing. I BELIEVE there is some work being done with .40S&W brass filled with lead and swaged into .44Mag bullets. WHY couldn't you do this with those Blazer aluminum cases. I am sure there are other caliber cases that can be used as bullet "jackets". I know for certain that the industrial grade foil will act as an abrasive from working in the steel mill machine shop. They would super polish parts with a "shoe" fitted with a piece of foil. Rubbing the "shoe" back and forth on the rotating part would remove MOST of the machining marks. Worked better than tooth paste!

Jim_Fleming
05-01-2009, 05:48 AM
Spoken like an EXPERT!

Quite true the difference between titanium and depleted uranium, titanium is almost as dense (heavy) as aluminum and quite hard. Where as uranium is as dense (heavy) as lead, but still quite hard!

Which is going to penetrate better gents? An aluminum bullet or a lead bullet? Both of them being about the same weight...

Uh-huh! Moral of the Story...? Don't get in the way of a SABOT round when fired from the barrel of a tank... :bigsmyl2:

I'm NOT a tank expert at all, I'm just a person that's worked in the metal cutting industry for the last 34 years...

Take Care,
Jim


The SABOT round penetrator for the M256, 120 mm gun used on the Abrams tank, is depleted uranium, not titanium. big difference. You are correct that the SABOT itself is a special alloy of Aluminum that is harder than wood pecker lips and twice as tough. The SABOT itself is not in heavy contact with the chrome plated smooth bore. The gun is capable of 2500 rounds or so before condemnation. Wear is not soo much the problem as is the elastic peak of the barrel as the gun operates at upwards of 100 thousand PSI. When I left government service in 2005, the round count was being constantly increased as that gun is one stout piece of work and the chrome lining resists wear very well.

Bottom line, Aluminum alloy in a 120 mm tank round and aluminum jacketed bullets in my rifle barrel are not a good comparison as the functions are not the same.

scrapcan
05-01-2009, 05:37 PM
Maybe this would be a good, cheap way to get a great finish inside of a self constructed swage die? I know that was way off topic of the original thread but we alllike a hijack once in a while.

NoZombies
05-09-2009, 07:42 AM
Quite true the difference between titanium and depleted uranium, titanium is almost as dense (heavy) as aluminum and quite hard. Where as uranium is as dense (heavy) as lead, but still quite hard!

Actually, Titanium is denser than Aluminum. Titanium = 4.54 grams per cubic centimeter. Aluminum = 2.7 grams per cubic centimeter.

Depleted Uranium is considerably denser than Lead. Lead = 11.34 grams per cubic centimeter. Depleted Uranium = 19.1 grams per cubic centimeter.

Titanium is much stronger (tensile strength) than aluminum, and often requires less material to preform the same function, thus yielding a part that has a lower overall weight. Titanium has also gained a certain "rep" among the masses as being a super metal, to the point that we're making wedding bands, watches, and even credit cards out of the stuff. I do love titanium, don't get me wrong, but it's not "lighter than aluminum and stronger than steel" like everyone seems to claim.

Depleted Uranium is used in military projectiles due to it's density and hardness. It can carry more energy to it's target than a lead projectile of the same size can, and provides better penetration due to the combination of density and hardness. Tungsten carbide is another metal used in military projectiles to provide penetration. at 15.8 grams per cubic centimeter, it's still much heavier than lead, and doesn't have the potentially harmful radioactivity that DU does, (though there are some associated carcinogens that aren't pretty,) an added benefit is it's high level of hardness, at approximately 8 1/2-9 on the Mohs hardness scale.

Of course, we haven't started to talk about alloys of the various metals. (Almost every end-user application of Aluminum or Titanium is in the form of an alloy.)

NoZombies
05-11-2009, 02:17 AM
And to answer some of the OP's questions:

Aluminum foil itself would be unsuitable for jackets for several reasons, these include:

Aluminum foil is very work hardened (this is why it tears instead of stretching) and very thin, even the heavy duty stuff is far too thin for an effective jacket, and couldn't be die formed into a jacket. (we're assuming you mean a real jacket, not an aluminum patch rolled around the bullet)

If you started with deep draw sheet aluminum you could potentially create jackets that would at least hold up to some reasonable velocities, but you'd need to anneal it several times during a multi-step drawing process, and have custom drawing dies made, because the steps would be different than for drawing a copper based alloy. When aluminum work hardens, it has a lot of stress fracturing that occurs, and might leave you with a bullet that blew itself apart down range without proper annealing steps.

Aluminum itself probably isn't a very good candidate for a jacket either, here's why:

Aluminum isn't self lubricating, and tends to gall, look at the top of an aluminum bullet mold that hasn't been properly lubed to see what I mean. This would probably leave you with bad aluminum fowling, and worse, eradic flight behavior due to the inconsistent and unpredictability of the way the jacket would (or wouldn't) gall in the barrel.

A chrome lined bore might make an aluminum jacket more practical for shooting, But it might not, and remember, the manufacturing issues would need to be overcome before it's even an issue.

Steel jacketed bullets are more practical for several reasons:

Steel can be more consistently drawn deeply to form with less annealing between processes, and less stress fracturing in the process as well. When fired through a chrome lined bore, They don't gall in the bore, or cause greatly increased wear. All of the guns specifically designed to fire steel jacketed bullets have chrome lined bores, giving a surface hardness that is considerably higher than the jackets themselves, and preventing (or reducing) the other issues that such a hard jacket might cause. Firing steel jacketed bullets in a non chrome lined bore is a pretty bad idea, and will cause severe erosion to the rifling at an incredible pace.

My 2 cents is that even if you could overcome the roadblocks with the manufacture of aluminum jackets, and had your bore chrome lined so you (maybe) could shoot them, there wouldn't be much, if anything, to be gained by doing so. The cost involved in being able to properly draw the jackets, and the necessity of special deep draw aluminum would make it even less practical.

All that being said, theory never works out the same as reality, and someone might try making aluminum jackets and have excellent results, and start producing the worlds most accurate bullets, but I'd be surprised if they did. [smilie=1:

Paul
06-06-2009, 01:05 AM
........then swage it to shape and not tear the foil?

If it worked, the result would be a very soft bullet with just enough jacket to prevent leading.


The question... not tear the foil? or prevent leading?

I would think the foil would tear, but there might be a process with lube etc.. to get a alu foil to cover the lead bullet..... maybe hard to do.

and Prevent Leading? Sure, if only Al touched the bore, you would not have any leading..... but maybe worst problems....

Paul

windrider919
06-08-2009, 04:05 AM
Aluminum makes a poor bullet jacket because it galls as it goes down the bore. The reason Silvertips bullets were not sold to the public was that they have a wax type lube on the bullet hidden by the case that reduces the galling. Winchester management decided that reloaders were not smart enough to keep the lube on component bullets and without lube they were very inaccurate. Hennce only loaded ammo being sold. So why make a jacket out of aluminum? Because it has great expansion characteristics in ballistic gelatin or in flesh.

As per the aluminum oxide wearing out the bore. Testing has shown that there is not enough on the bullet surface to do that. I read an article where it was determined that the oxide, which forms instantly in the presence of oxygen, did not form in a firearm barrel because some propellant gas always passes around the bullet before it fully enters the rifling. And that puff of gas is oxygen poor. The bypass gas then is pushed down the bore ahead of the bullet, shielding it from any further contact with oxygen. So the Aluminum jackets worked sort of in pistols but there was not enough lube to keep galling down in long barrels. I used to own a Fox Auto-carbine in 45ACP with a 16" barrel. I found out all the above because I shot 250 WW Silvertips one afternoon and fouled the barrel so bad it was uncleanable. I contacted WW and found out where I had gone wrong. They also had me send the rifle to a shop where they cleaned it electrolytically, ie: they de-plated the aluminum from the bore.

Finally, I am mostly a PP shooter and I tried Al foil a long time ago. The biggest problem is the difference between paper and Al. With a paper patch we wet it and the layers stick to itself as it dries. when you wrap the core with Al foil the foil stays loose and the edge can lift up: in seating, in the box and most definitely when chambering. But we shooters will try anything, right. so being super careful I did get undamaged Al patched bullets into my .458's chamber. I shot 30 rounds in 5 shot groups. The Al patches shed at the muzzle like they were supposed to, just like paper. We have not really determined what is happening here. Theory one is that the muzzle blast exiting around the bullet as the base exits shreds the patch. Theory two is that bullet rotation creates centrifugal force that throws the patch off. Or perhaps a combination of the two. I have been trying to get a high speed camera to film PPs coming off to prove it one way or the other but have not located one yet. Why I did not proceed further was because accuracy was extremely poor. I could have thrown rocks and gotten better groups. No load development here, 4 ft groups at 100yards says it all.