Ballistic properties of rocks

O

Oleg Volk

Staff Alumnus
Has anyone ideas on what a lathed and jacketed (or saboted) rock would do if fired from a pistol or a shoulder arm?
It could be sandstone or sm-th else that is relatively easy to work...

I am curious on 1)would it work at all 2)what kind of damage to target it would inflict 3) what kind of accuracy can be expected?

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Oleg "cornered rat" Volk (JPFO,NRA)

http://dd-b.net/RKBA
 
kind of an unstable, non uniform, fractured material

sandstone especially
not as dense as lead

better option
cast plastisized concrete!

neither is going to expand, more likely to either shatter or fragmentize

since both are silia containing, i would bet it would be hell on rifling

planning on stoning a target?

;)

dZ
 
In a sabot it will not wear out rifling. I am just curious if rocks in bamboo or other type of a sabot could be used in muskets if lead is not available.
 
Oleg,

What an interesting and unique question. I do not think that a "rock" would be a very good projectile out of gas propellant operated guns like we commonly have at our disposal. If you can find some containing a high percentage of various ores, and then purify it to an acceptable degree (ie.smelting), cast or forge the bullets, it may work. But then, that is what we have today... I think that raw iron would work, for instance, but be very damaging to the bore of your firearm. Its just too hard.

On the other hand, there are a range of slings and sling shots that can mechanically propel stones of different sizes (calibers) and densities with relative accuracy and effectiveness. Catapults were used throughout ancient history to propel large stones at long ranges, as a precurser to the cannon. A movie I saw once showed farm livestock being hurled by a catapult, even a cow. (Monty Python's Holy Grail?). On a smaller scale, I fondly remember the days as a youth going rabbit hunting with my ol "wrist rocket". However, I don't think that I'd try that w/the rabbit in the movie. If the Holy Handgranade couldn't "snuff it", I do not think a wrist rocket would either. ;) With plenty of practice over the years, I was able to place a round stream stone in a tennis shoe sized target at 30 yds. Lots of fun and effective for small game out to 25yds.
As to your questions:

If you jacketed a stone, consisting of hard minerals, that you took time to jacket w/copper after forming the rock to the appropriate dimentions, it may or may not leave the barrel. Even jacketed bullets contain lead. The propulsion (ie. velocity) and accuracy would be determined largely upon the seal that is made by the bullet. Bullets require lead because it is soft enough to conform to the groove/lands of the barrel. Hard minerals would not do this and may become wedge, causing the barrel to "back fire" or KB. Shotguns have used steel shot effectively. I believe that if you used an appropriate sized barrel of a muzzel loader, you might be able to shoot rocks, nails, clams, or any such critter of suitable size. Again, I believe that it would be very limited as to accuracy, range, and safety.

One of the most effective stone projectile weapons in history for medium range combat was demonstrated by King David of Israel as a young man; eventually to become a great grandfather to Messiah. He was expert w/the simple sling. This consisted of a short stick w/a long leather strip or rope connected on one end to the end of the stick. There was a pouch to hold the stone out at the full extension (half the length) of the cord. Having gained his confidence from a promise given by the Lord to Israel, he decided to exercise faith in that matter of Bible doctrine. Having chosen smooth brook stones, one for Goliath and each of his brothers, he went to the battlefield. Upon reaching the greatest Philistine warrior he said, "...I will smite you, and take your head from you; and I will give the carcases of the armies of the Philistines this day unto the fowls (vultures) of the air and to the wild beasts of the earth; that all the earth may know that there is a God in Israel!" He then proceeded to chamber a 1.0+" caliber stone into his days' version of the handgun/possibly shotgun. He used a simple, yet highly effective weapon, by the providential grace of God, to hit the only open spot in the heavily armoured steriodal freak of nature. The stone sunk into the frontal lobe of the freak's brain and David then proceeded to sever Goliath's neck, divorcing the head from the carcass with it very own sword! I Samuel 17:46-54

Sorry to go on so long, Oleg. I hope that you aren't sorry that you asked the questions now. This is one of my favorite passages from the Prophets and the subject happened to remind me of it.

robert
 
Yes, MOST interesting. Personally, I wud not swage the rocks. I wud just use a good small peen to seal the ctg. mouth on the rock and just fire it raw. It might be a bit rough on the rifling, but if used in a M1911 custom gun, a new barrel is easy enough to install. Or just pouring gravel in a AA shotshell wad would be a good test of dispersion factors and vectors. A good experiment.

Barrel Makers of America
 
Moving to General...as it seems that nobody has a lot of experience in loading rocks, this will probably get the best response in General.
 
<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Oleg Volk:
In a sabot it will not wear out rifling. I am just curious if rocks in bamboo or other type of a sabot could be used in muskets if lead is not available.[/quote]

Now I see what you are getting at. Would this be for hard core survival training? A just in case scenario? :D I've know some who have shot ROCK salt in the manner that you have described. The issue w/a muzzle loader probably comes down to the charge, size/shape of the stones, and how many barrels you want to replace. I do not think that stones would give the penetration that a denser material like lead would.

One of the history channels shows tonight had "Early Guns" featured a painting of the middle ages where a sling similar to David's was employed in battle. Early inventors had some similar ideas to you Oleg. A muzzle loader was produced that would shoot arrows. The shafts were oak, and they had leather washers to cover the charge. They were used in England and Germany at one time. When they improved the gun by using a real lock, stock, and barrel, they almost made the bolt shooting crossbow obsolete, because reload times were shortened. Just a little bit of trivia I picked up tonight.

The combination of rocks and the modern firearm gives capitol punishment a new meaning. We could turn a firing squad into an old timey stoning! ;)

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"But now, he that hath a purse, let him take it, and likewise his scrip; and he that hath no sword, let him sell his garment, and buy one." -Jesus Christ (Luke 22:36, see John 3:15-18)
 
Did you just see that Star Trek re-run? Where Kirk and some humanoid lizard are being tested mano a mano? Kirk is getting whupped and he finally finds a chunk of bamboo, diamonds, charcoal, sulfur and nitrate...he makes a crude cannon and whacks Mr. Lizard.

For rocks, a short range cannon would work...same with huge rocks...cannon.
For longer range accurate rifle type I doubt rocks/pebbles would be any good due to low density
 
Yea DC,

That was my favorite episode back when I was a kid! Lizard-Man vs. Capt. Kirk! So THAT's where Oleg got the idea from... I should've guessed.

When the bolder that Kirk pushed off of the top of that hill didn't dispatch that Lizardsaurus, I figured he might as well forget trying to kill it. It can't be done. But the wonders of primative ballistics...Wow, I'd realy like to have one of those in my collection. I'd put 'em in the cage w/my water monitor. I think they'd get along well together.

Well, THERE'S your answer Oleg! Just find out when they are showing that rerun again and tape it. If it can put a Lizard-Man to sleep, it can surely take down any mortal man or beast this side of a Griz. :)
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"But now, he that hath a purse, let him take it, and likewise his scrip; and he that hath no sword, let him sell his garment, and buy one." -Jesus Christ (Luke 22:36, see John 3:15-18)



[This message has been edited by EQUALIZER (edited February 18, 2000).]
 
Rat have you been eating those peanut butter and sardine sandwiches before going to bed at night again? :)

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Gunslinger

We live in a time in which attitudes and deeds once respected as courageous and honorable are now scorned as being antiquated and subversive.
 
Obsidian would make a great sabot. Once accelerated its terminal ballistics would be great as it would make a very effective anti-personell projectile. Obsidian is generally very homogenous and does not have a micro-crystalline structure as does a granite for example. As a result, when its struck (or decellerates quickly), it creates a bulb of percussion that sends energy in waves through it, thereby removing extremely sharp flakes. These are kinda like super fleshings, and would be very effective in CQB.

My $0.02
 
Interesting topic. Just last week, I saw an edition of Arms in Action on The History Channel concerning this very thing. Experts at the Royal Armory in England had built replicas of many early cannons, including the "vase" shaped one shown in a tapestry that is the earliest known depiction of any type of gun. It launched an arrow, and their reconstruction was able to launch one succesfully, although the shaft broke in two. They also showed slow-mo of one of the giant siege cannons shooting stone balls at stone walls backed by earth. The results were that the projectile was smashed to pieces, and a small chunk of wall was powedered along with it.
I saw another edition of the same program last night, and it covered early guns, the one known as "handguns", which were basically barrels with nothing but a metal handle on the breech end. They discovered that firing a pure lead ball of .50" diameter using sixty five grains of black powder resulted in a velocity in excess of 1300mph and was capable of penetrating two 1/16th" sheets of plate metal. Armor of the time was usually about 1/16" thick. Fifty grains of BP gave enough veleocity to cause the same ball to penetrate at least one layer of armor. Pretty hefty stuff, considering the projectiles were pure lead.
If you have not seen the Arms in Action series, it is well worth a look. The very first one I saw was dealing with swords, and it dispelled some misconceptions I had about broadswords. Production values of this show are very good. The Royal Armory has a number of people working for it that make and use weapons according to old manuscripts and records, and then dress in period dress and stage carefully choreographed mock battles using authentic tactics and techniuqes. I was amazed to discover that the two handed broadsword, utilized according to a 500 year old rare training manual, was extraordinarily agile. The shagreen (shark skin) cover in front of the hilt on the blade was used as a second hand hold for a maneuver in which the user grasps the end of the blade in one hand, the cover in the other, and does an overhand stroke which employs the guard as a skull crusher. It can be switched to this mode from a standard grasp in just the blink of an eye.
Again, if you've never seen any of these, keep an eye out for them and be sure to fire up the VCR. Great stuff.

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Shoot straight regards, Richard at The Shottist's Center http://forums.delphi.com/m/main.asp?sigdir=45acp45lc
 
I remember a humorous bit written by Col. Cooper in his old American Handgunner column. (Yes, that was a _long_ time ago.) It seems that a competitor at an IPSC match made the comment that he could make the ballistic pendulum register at least Minor by simply throwing a heavy rock at it. Cooper said that the fellow was most welcome to compete in the match with a pocket full of rocks, but that scoring the targets might become problematic. ;)
 
even if you jacketed a piece of rock, ceramic, or whatever, you'd have to be careful about pressure. most loads are developed with lead-core bullets; when the bullet hits the forcing cone and engraves, the surface stresses move the jacket *and* core. pure lead or alloy thereof is still soft relative to the engraving forces. a hard core will resist deformation, increasing the surface pressure (and thus friction) between the jacket and bore. more friction, more chamber pressure. obviously this is a solvable problem, since we have AP ball and whatnot (not to mention homogeneous bullets like the Barnes copper jobs), but a different powder charge would have to be worked up.

that obsidian concept is downright scary. :0

I kinda like the medieval approach; 400 lb of granite at 200 fps. even Fackler would approve. ;)
 
You ought to se how far a one ounce piece of lead flies when thrown out of a crude homemade sling. Basically two pieces of string and a cloth cradle. I have thrown in an arc a one ounce piece of fishing lead over 100yards. With patience and practice could hit a man sized target at 20 yards. BUT be careful, the wrong sling and you will be repairing windows :D

On the same thought, I have a lot of spare fishing lead laying around, in a pinch, I could shape the lead with a knife and hammer. Given a smooth bore, some powder, I believe that I could make a crude firearm. I of course would tie it to a try to test fire the dang thing! :eek: That is some of that Redneck Engineering.

But a stone had better be perfectly round or its horribly inaccurate, when you impart a spin it may try to fly like a frisbee. At worst, in extreme circumstances, I believe I could make a bow, a sling, or a spear. I'd save the rocks and gunpowder for booby traps.

Do I have to leave my name? Hehehe.
BTW, don't try any of this at home, go to a friend's house. :rolleyes:

DaHaMac
 
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