Round ball min expansion velocity

[Griz44Mag]

If a ball hits an immovable object like a steel plate, it will take far less velocity (to deform) than if it hits a more elastic decelerent like liquid, or soft tissue.

From the many steel plate matches I have attended and conducted both, I can assure you that a soft round ball that hits a steel plate at 100 yards will splatter like a drop of water on a sidewalk.
From the bystanders point of view - it looks more like a dust puff.

 

[Col. Batguano]

It splatters because the decellerational G-forces involved in the projectile hitting the plate have exceeded the strength of the molecular bonds' and the elasticity / malleability of the projectile --lead--and their ability to stay "stuck" together. At lower velocities / G-forces they will not splatter.

As far as terminal effectiveness goes, because the mass of the splattered droplets is so small, their secondary abilities to cause wounding is small as well. The higher the velocity, the greater the propensity to splatter. That's why if you hit something hard (like bone) with a bullet going too fast you may not cause an immediately fatal wound. Their energy is radiated outwards, and less so inwards. As velocity increases, the resistance of the medium is squared due to the nature if the incompressibility of liquids (the shock wave).

Have you ever done the science experiment of mixing corn starch in a small dish full of water? Stirring slowly with your finger, you feel almost no resistance. Stirring faster, it gets harder and harder to stir it. Using this concept, the military is currently experimenting with making body armor from multiple flexible liquid-filled cells. They will conform to the wearer's normal body movements, but stop a bullet and not transmit the shock from stopping it deeply inside the wearer.

Anecdotally, I shot a small deer one time with a 308 Win at 15 yards and hit him in the shoulder with an ordinary soft point bullet and never found him, despite tracking him an hour and snow on the ground. (it was warm and raining too so the trail just petered out.) I'm sure the bullet "blew up" and didn't (immediately) cause a fatal wound. That's why I won't hunt with those bullets any more--only partitioned ones.

I'm pretty sure the accellerational G-forces inside the chamber exceed the projectile's ability to stay stuck together too, but, because they are contained by the bore and chamber, they don't fragment. They essentially "re-weld" themselves back together to take on the shape of the bore and get swaged in to the rifling. That's why low velocity loads may not be as accurate as higher velocity loads. They're not swaged enough to be accurately guided by the rifling in the bore. At very high loads, they exceed it too, and accuracy diminishes. That's why there is a "sweet spot" regarding loads.

So, looping back to the original question; the projectiles' mushroom and staying together as an effective bullet really depends on what you are shooting it in to. Bone has a higher coefficient of resistance / deceleration than soft tissue. Like accuracy, there is a "sweet spot" depending on what it is made out of. You want an impact velocity that will hold it together if it hits bone, but can still mushroom and cause hydrostatic shock if it only hits soft tissue. Absent that (hydrostatic shock and secondary wound channel) the sheer size of the primary wound channel can still get the job done (like an arrow does). That's why game departments establish minimum broad head diameters as being legal for archery. There is no (significant) secondary wound channel with an arrow.

 

[Old Hawkeye]

Having never exposed my balls to Georgia Summers, I cannot add any evidence.
ADK Bigfoot

I'm not going to comment other than if you do, apply some sunscreen.

 

[Okie Hog]

So, looping back to the original question; the projectiles' mushroom and staying together as an effective bullet really depends on what you are shooting it in to. Bone has a higher coefficient of resistance / deceleration than soft tissue.

This^^^^

One of my range backstops is at 76 yards from the firing bench. My powder loads generate 1,500-1,600 fps at the muzzle. .50 and .54 caliber round balls hitting the clay bank at about 1,000 fps always expand and are sometimes nearly totally flattened.

Most of my shots on deer and hogs with patched round are at ranges <60 yards. i like high shoulder shots or high just behind shoulder shots on deer. Those shots interrupt the central nervous system and you have a bang flop.

This young buck was shot at 38 long paces:

This deer was killed at about 25 yards from a tree stand:

 

[smoothshooter]

They would put the recovered ball in their mouth and ’chew it round’. We do it with chewing gum and can make them almost perfectly round, round enough..

With the dental practices at the time ( or lack thereof ), I would not have done anything to risk damaging my teeth.
I remember reading in a part of James Smith’s memoirs about how he once had to have someone pull an infected tooth he had with a bullet mould in the 1770’s or 1780’s.

 

[hanshi]

And ball expansion isn't an all or nothing occurrence. Depending on whether or not a bone is struck, the degree of expansion varies with impact velocity and material penetrated. Having killed deer with quartering shots that didn't hit bone, the ball flattened impressively after going through 2' to 3' of soft tissue.

 

[Sun City]

All so much BS! I know if I poke a big Oklahoma whitetail behind the shoulder with my .54 Hawken using 100 grains KIK 2F powder.....he ain't going far!! All this 'theory crap' comes from folks that have been shooting modern stuff for years and basically don't know owls..t from wild honey about the capabilities of blackpowder ML rifles!!

 

[Sparkitoff]

I'm with Sun City. I already showed that around 55 FPS expand a ball if it hits a concrete wall. Yeah, just 55 FPS. That is a direct answer to the original post. A softer target did not expand the ball at the same velocity. And with all due respect I can't believe there are any G -Forces on the ball I threw at the wall. I upped my experiment just a little. I used my slingshot with .454 balls and a chronograph. An average of 154 FPS a foot in front of the slingshot has the balls slightly flat when they hit a full plastic gallon jug that is filled with tap-water. A few cracked the plastic and some didn't. Either way the balls had some flat spots of expansion. So Speer .454 balls expand at 154 FPS on milk jugs that are 12-yards away. That directly answers the question too.

 

[Black Jaque Janaviac]

Hello all,

I hope all are doing well and not sick with the flu that seems to be everywhere!
i have been wondering what the minimum velocity would be for a pure lead round ball to expand would be? I know that they say that 800 ft/lbs of energy is needed to kill a deer humanly. I don’t know if that’s correct or not and don’t care. I do care about my 62 caliber Leman flintlock will produce enough velocity and energy to expand though. Expansion equals damaged soft tissue which equals protein on my table! And that’s a win!

thanks, Don M
From Pittsburgh, Pa

Hi Don. The expansion thing is a little confounding to me. I've been casting my own for nearly 25 years. I had a .54 Lyman GPR and was shooting balls cast from old telephone sheathing. Had pass-throughs every time. About 2001 I got a new .54 flintlock and my telephone sheathing source dried up and I started casting from sewer lead. I started recovering balls on the far side of the hide. Not every time, but with some frequency.

The GPR was throwing them at 1690 fps, but it probably wasn't a pure lead. The flintlock (longer barrel) throws 'em at 1900 fps, and the sewer lead is soft as bubblegum.

So if you have a chronograph and can get your ball going soemthing between 1700 and 1900 fps you should see some expansion if you have soft enough lead. However with a .62 you may get pass-throughs even so, which will make it harder to tell if you're getting expansion.

What many folks will tell you is true though - the roundball doesn't need to expand. The modern bullet is designed to cut through the air without losing energy (an the consequent velocity drop). But once that modern bullet strikes its target, the hunter wants the opposite of the energy conserving shape - so bullet manufacturers come up with clever designs to maximize expansion. Thus the expanded bullet loses its sleek shape and begins dumping energy as it decelerates. A roundball is very, very, inefficient at cutting through the air, thus it begins dumping energy at a ridiculous rate the moment it leaves the barrel. It still dumps energy inside the deer's vital tissue.

I will say, however, that just by experience and anecdotal evidence - it seems that the .45 ball produces the most bang-flops on whitetail of all the roundball calibers. But what produces a dramatic bang-flop with a perfect hit, may also produce less than satisfactory results when a deer is hit through a shoulder or arm.

 

[hanshi]

I will say, however, that just by experience and anecdotal evidence - it seems that the .45 ball produces the most bang-flops on whitetail of all the roundball calibers. But what produces a dramatic bang-flop with a perfect hit, may also produce less than satisfactory results when a deer is hit through a shoulder or arm.

That's been my experience on deer as well. Another thing I've experienced is the difference distance has on the round ball. Close up, say 50-60 yards or less, usually has the ball flattened out just under the off side hide. And this is without bone being struck. If bone is struck the ball WILL deform. At 75 yards and farther complete penetration has been the outcome unless a bone is struck. But even at 100 yards and full penetration they dropped about as fast as with closeup shots.

 

[Griz44Mag]

Hi Don. The expansion thing is a little confounding to me. I've been casting my own for nearly 25 years. I had a .54 Lyman GPR and was shooting balls cast from old telephone sheathing. Had pass-throughs every time. About 2001 I got a new .54 flintlock and my telephone sheathing source dried up and I started casting from sewer lead. I started recovering balls on the far side of the hide. Not every time, but with some frequency.

The GPR was throwing them at 1690 fps, but it probably wasn't a pure lead. The flintlock (longer barrel) throws 'em at 1900 fps, and the sewer lead is soft as bubblegum.

So if you have a chronograph and can get your ball going soemthing between 1700 and 1900 fps you should see some expansion if you have soft enough lead. However with a .62 you may get pass-throughs even so, which will make it harder to tell if you're getting expansion.

What many folks will tell you is true though - the roundball doesn't need to expand. The modern bullet is designed to cut through the air without losing energy (an the consequent velocity drop). But once that modern bullet strikes its target, the hunter wants the opposite of the energy conserving shape - so bullet manufacturers come up with clever designs to maximize expansion. Thus the expanded bullet loses its sleek shape and begins dumping energy as it decelerates. A roundball is very, very, inefficient at cutting through the air, thus it begins dumping energy at a ridiculous rate the moment it leaves the barrel. It still dumps energy inside the deer's vital tissue.

I will say, however, that just by experience and anecdotal evidence - it seems that the .45 ball produces the most bang-flops on whitetail of all the roundball calibers. But what produces a dramatic bang-flop with a perfect hit, may also produce less than satisfactory results when a deer is hit through a shoulder or arm.

With a hole as big as a .62 is going to make, it does not matter if it expands or not. Even a hardened steel ball bearing that big would be mortal.
On a hunt some years back a fellow hunter left his stuff at home but stopped at a dime store and bought a bag of marbles. He took a deer home that trip, and recovered the marble. It did not break and it also did not expand. It's now glued to the mount below his wall hanger.

 

[olskool]

a round ball of 45 cal. is about as large in diameter as a 30 cal. modern rifle will ever hope to expand anyway! a round ball is what a modern rifle shooter try's to achieve. when a modern bullet mushrooms it turns into a round ball. no expansion is needed on round balls,,,,,,,,,,,,,,,,