What is ithe deal lead hardness for falling plates?

[igolfat8]

I shoot in pistol competitions at steel falling plates. I primarily shoot 9 mm and my lead hardness is about 14 Bnl. The cast bullets average in the 1100 FPS range. When the bullets hit the plates they fragment into a puff of smoke. Do you think there would be any advantage of using harder or softer lead? Perhaps softer or harder lead may stay on the plate longer? Does anyone have any ideas which hardness would stay on the plate the longest and transfer the bullets energy the most efficiently?

[John Boy]

Does anyone have any ideas which hardness would stay on the plate the longest and transfer the bullets energy the most efficiently? Sure, Electro Type with a Bhn of 23! But why bother if the plate goes down with any lesser Bhn or goes poof when the bullet hits the plate

[runfiverun]

softer lead isn't as brittle.

[Petrol & Powder]

If you're talking energy transfer, I can't see how it would matter. The lead will always be softer than the steel and the amount that the bullet deforms is irrelevant as long the plate falls.
The bullet will have a certain amount of kinetic energy based on its mass and velocity. The hardness of the projectile doesn't affect the kinetic energy of the projectile. It might be a factor in the size of the fragments (and therefore the energy of individual secondary projectiles) disbursing after the impact but at that point the bullet has done its work on the plate. So for safety, a soft lead bullet may be preferable to a super hard one but I don't see 7 BHn bullet transferring the energy to a hardened steel plate any better or worse than a 20 BHn bullet.

[Oklahoma Rebel]

yes, it does ,when the boolit hits energy is lost to not only the target,but heat, the re-direction of energy aka the boolit breaking and shattering, aka lost momentum, and technically some to sound and light, just a weee bit. a softer boolit will deform over a longer period of time, thus transferring more energy to the target. so going down 2-4 bhn's couldn't hurt, but how much also depends on wether your gun still shoots well with the softer boolits. good luck, Travis

[mwc]

I use PC'd boolits, 147 grain TC shaped, BHN is 11-12, with maybe 2% tin and a bit of copper, doesn't make it harder but tougher, or a bit more elastic

[igolfat8]

Thanks Rebel and others for your opinions. I thought maybe softer bullets may spend more time on the plate and equal a slightly better energy transfer. Our outdoor season is over now so I have plenty of time to experiment over the winter months. Tonight I shot some 14 Bnl with some 10 Bnl and saw no significant off hand accuracy differencs on paper. I will inspect my barrels tomorrow and see if the softer bullets left any thing behind in the pipes.

[igolfat8]

How do you add copper?

[Petrol & Powder]

yes, it does ,when the boolit hits energy is lost to not only the target,but heat, the re-direction of energy aka the boolit breaking and shattering, aka lost momentum, and technically some to sound and light, just a weee bit. a softer boolit will deform over a longer period of time, thus transferring more energy to the target. so going down 2-4 bhn's couldn't hurt, but how much also depends on wether your gun still shoots well with the softer boolits. good luck, Travis

I don't wish to split hairs but I have to question how much it would matter. That energy has to go somewhere and we want it to all go into moving the plate. Obviously, not all of the available energy goes into performing the desired work (moving the plate) and some of that energy gets wasted by deforming the bullet, creating heat and maybe some other areas but just how much is lost? Is it even remotely significant in that application?

The steel plate is far harder than any lead bullet. So the steel plate isn't going to deform much (we hope) and most of the available energy goes into moving the entire plate. Once that plate begins to move does it really matter if the bullet is still deforming? Does it really matter if the bullet disintegrates into very small fragments or one big deformed chunk?
Our goal is to move the plate. While I'll agree that some of that available energy is lost doing other work (like deforming the bullet), at that point we've probably accomplished our task.
I have to ask, "just how much is lost doing other work and does it matter?"

[country gent]

On the swing shillouettes I shoot ( BPCR) i think the softer alloys of 20-1 or so seem to give a better ring and more swing than the harder bullets do. Also the shots "splatter" marks on the painted targets seem bigger than harder bullets do. When spotting in the binoculars I use (25X X100) i see the bullets trace into the target and the cloud from the bullet turning to dust and there is a diffrence between hard bullet and soft bullets but its hard to describe. Youll be surporised how the bullets break down. Look under the targets and youll find the thin lead discs laying these are whats left of the base of the bullets. I believe the softer bullets deform more before coming apart thus holding the target longer but its probably only miliseconds..... Im shooting much heavier bullets at 365 grns up to 550grn at longer ranges out to 500yds. On chickens with the 550grn bullet at 200 yds They almost wrap over the hanger rod. Try casting some soft 20-1 or around 9-10 bhn and some harder 13-14 bhn and maybe even tis alloy water quenched and see how they work on the falling targets. A solid hi with adequate load should topple them every time with all bullets.

[JonB_in_Glencoe]

softer.

softer alloys are heavier...more weight equals more energy.

[Oklahoma Rebel]

jon b, didn't even think of that one,lol and some ask, what difference does it make? it is only touching the target for a millisecond, but consider how much remaining muzzle energy is acting on the target in those milliseconds, and you would be surprised at the amount of energy used up in the shattering of a boolit, im not sure, but its a good percentage.

[Petrol & Powder]

................... and you would be surprised at the amount of energy used up in the shattering of a boolit, im not sure, but its a good percentage.


You concede that you're not sure but then you say "...but its a good percentage".
OK, I'll bite, what is a "Good percentage?" 50%, 25%, 1%, .00326%??????

I don't believe you know the answer and cannot defend that statement.

[reddog81]

10 BNH, 14 BNH, or 20 BNH the bullet is going to shatter irregardless. If the load functions, is accurate and doesn't lead the barrel I'd say you are good. If anything the more lead and less other stuff, the heavier the bullet and that is probably going to have a larger effect like previously mentioned.

[fecmech]

As long as the target falls easily I would stay with the more brittle bullets. Pieces of lead can come straight back off targets with dents and craters in them. Brittle bullets = smaller pieces. I've seen pieces of bullets come back to the firing line from 50 yd pigs and been hit a number of times over the years from shot coming back off trees on sporting clays courses.

[Ola]

If the hardness doesn't matter, I wonder why "siluette-bullets" have thick jacket and though construction?

Just for fun, I suppose..

[merlin101]

softer.

softer alloys are heavier...more weight equals more energy.
NOW That I can understand! the rest not so much. Keep It Simple, thanks JonB!

[mwc]

Pewter has copper in it and also several of the babbit materials from rotometals has it in along with tin and antimony.

[fecmech]

If the hardness doesn't matter, I wonder why "siluette-bullets" have thick jacket and though construction?

There is a big difference between falling plates and silhouette. In silhouette you have a ram target that weighs approximately 55 lbs and must be knocked over to score a hit. That requires bullet weight,velocity and in cases where those two are marginal dwell time on the target helps. Falling plates can be knocked over with .22's.

[Oklahoma Rebel]

petrol, im not sure you can read either. in that statement I said im,not sure,but a percentage yadayadayada....what do you want me to say,duuuhhh.. I dunno..duuuuhhhh.....

[Oklahoma Rebel]

I have made one mistake though, I assumed he meant sillouette, are you talking about what they have in three gun

[Oklahoma Rebel]

and so you believe it takes no energy to shatter a boolit? I must concede, your knowledge is far superior to mine., well don't just stand there, go help nasa with interstellar space flight (petrol&powder)

[Oklahoma Rebel]

igol , would like to know more about your competitions? what all is involved, could I start with a pistol like an old cz52, or even a model 15-2 S&W 38spl? and whats the farthest distance on the course?

[skeettx]

OK, my take on the situation
9mm
The bullet has to have a certain hardness to be accurate and not lead the barrel.
The bullet must be cohesive enough to take down the falling plate.
If you can do this with your current bullet and there is no safety issue with fragmented bullets
Then stay the present course.
Mike

[Oklahoma Rebel]

yup, definetly fit first, if you don't hit the target it wont do no good, no good et'all

[Ola]

Falling plates can be knocked over with .22's.

So basically this whole discussion was about nothing :)

[igolfat8]

igol , would like to know more about your competitions? what all is involved, could I start with a pistol like an old cz52, or even a model 15-2 S&W 38spl? and whats the farthest distance on the course?


In three gun: we shoot 6 steel falling plates and 2 poppers at 100 yards with a rifle, typically AR is the rifle of choice. Next we move a few steps to shoot 6 clays on 3' high posts at 20 yards with a scatter gun and 12 gauge autos are the weapon of choice. Last we move a few steps to shoot 6 poppers at 50' to 40 yards with a cente fire pistol of choice. 9s are the most popular with a few .40 and .45s taking the back seat. There must be a reload with shotgun and pistol.

We also shoot pistol competitions on Monday nights. Our club competes against a neighboring club. We used to shoot bowling pins but we ran out of those at our club so we moved to shooting steel on a falling plate rack. We still shoot pins at the other club because they hadn't run out of pins yet. We shoot pins at 30' and steel plates at 50'. Pins will easily fall over with 9s if you hit them square so it remians the most popular caliber. We race against the clock and the fastest times have been with a 9 followed by 38 super then 40 and lastly .45.

When we we shoot steel at our club 9 remains fastest (IF) the shooter does their part by hitting the plates HIGH and 2/3 above center. 38 super is very fast but they can hit the plate anywhere, they fall and sometimes they come back up because they have so much power. 10mm is same, they are too powerful. The plate must stay down and if it pops back up its scored a miss. You can get, sloppy with .40 & .45 and the plate goes down and stays down. Rarely does a plate come back up with either of the latter two calibers. 9s remain the fastest times but if you hit the plate below high center the plate won't fall.

9, 38 super and 10mm bullets all disappear with a puff of smoke when they hit the steel plates. The only lead coins found below the targets are left over remnants of .40 and .45. I assumes it's due to the lower velocity of the slower bullets? Since I can't lower the velocity on 9 and still have enough oomph to fell the plate I wondered if making the Boolits softer might have some positive benefits and hence the nature of this thread.

[dverna]

It would be interesting to shoot the plates off a bench with three different alloys 10, 15 and 20 Brn. Aim for center and 1/3 from bottom and see the results. 10 shots should give an indication of how each parameter affects results. 60 rounds total.

If there was a difference, it would warrant further testing to verify.

Don Verna

[Rattlesnake Charlie]

igolfat8
Thanks for providing useful empirical data.

dverna
Thanks for providing a good scientific approach.

[ironhead7544]

Load some of each and test them. Then give us a report.

[runfiverun]

add more flat to the nose.
that will make more difference than 3-4 bhn.

[igolfat8]

Load some of each and test them. Then give us a report.

Great idea!!! I will but unfortunately it will have to wait until next year. Our outdoor season has come to a close. The plate racks are put away and they are moved around with a tractor which I don't have access to ;(

[Oklahoma Rebel]

if these plates can be knocked over with a 22, then they are much smaller/lighter than I imagined. runfive, a nice flatpoint always helps.i am using a 425gr rnfp for deer this year

[Ballistics in Scotland]

You could adopt the principle of an early ballistic pendulum. Take a hinged plate, or one which will skid back along a horizontal surface rather than fall down, and attach a piece of strong, smooth string which it will drag through a small eyebolt. You can't push string back through a hole, so it will tell you how far the plate has moved under the impact of different bullets.

Both soft and hard bullets can break up. I don't think heat by hysteresis in the metal is very significant, but if kinetic energy is directed sideways, it isn't being directed forwards. It might pay to fix a wooden box, or piece of the thick cardboard tubing carpets come rolled around, onto the face of the plate to trap fragments. You can learn a lot from the nature of the fractures, and tailor your bullet alloy to minimise them.

[igolfat8]

if these plates can be knocked over with a 22, then they are much smaller/lighter than I imagined. runfive, a nice flatpoint always helps.i am using a 425gr rnfp for deer this year
You can't knock our plates over with a .22 unless it has a 3 at the end of .22 ��

[Oklahoma Rebel]

ahh ok.

[igolfat8]

Our plates are 1/2" x 8" AR-500 steel.