Stopping power experiment. Tips?

[AragornElessar86]

I'm looking to do an experiment to compare the stopping power, as energy transfer per penetration distance, of various major defensive handgun ammunitions. So far I'm planning to set up the experiment by firing straight down into ballistic gel placed on a scale or other measurement device that will capture the peak force of the impact, then divide that number by the total penetration distance. I'm looking for any and all commentary on this setup and my proposed calculation concepts.

[CalTeacher]

I mean this honestly, and in no way as an insult, but you're wasting your time trying to find the stopping power of a handgun round. Stopping power and handgun don't really belong in the same sentence. Stopping power is a concept that sounds great in theory, but can't really be measured. There are many more important things that contribute to stopping a threat.

But feel free to experiment away if that's what floats your boat.

[Wolfie_AR]

Check out the Box o' Truth website. That guy has tested a lot of rounds in may different ways. Rifle, pistols, shottys. He uses, ballistic gelatin, drywall, bottles of water, clothing material, cars, steel plates, etc. Depending on what he wants to test.

[Whiterabbit]

I agree. What if one bullet stops after 6" but makes a 6" spherical wound channel in the gel? And the other has full penetration with no wound channel at all, just zips right through the gel, your scale, and imbeds 12" into the ground?

Which one has more stopping power? You wouldn't know, cause your scale would be broken.

[Ken Woodford]

I have to agree with the replies say.

If you look on paper the .223 would outperform the .30-30 at 100 yards. Bowling pins at 100 yards...hit one with a .223 and then one with a .30-30...see which caliber knocks the pin back the furthest.

There of course many variables that come into play mainly bullet weight in the above scenario. Stopping power should be measured in real life incidents and not on paper or in gel. Although seeing a bullet go through gel is pretty cool.

[AragornElessar86]

Wolfie, I've seen BOT's stuff, and it's not as scientific as I'd like. I'm hoping to come up with some sort of unit of measure like Nm/in or something.

Whiterabbit, I'm planning on using a very tall column of gel to prevent that.

I'm aware that energy transfer isn't the be-all, end-all of SD/HD, but you have to admit it's pretty important or we'd all use .22lr pistols.

[XDRoX]

My buddy made some gel and we shot it up at the desert. It was very fun. We tried a variety of SD rounds. The funny part was the only round that went clear through the 18" of gel was a 22 shot out of a 4" Walther. The gel stopped all the larger rounds.

After we were done experimenting we shot it with a 308. It blew the whole block apart into a thousand pieces.

Fun time.

[Dark Mod]

Our hobby involves alot of experiementing and analysis so you should be commended on testing this where others wouldnt bother.

I for one would be interested in your results. I have never worried enough about stopping power to look beyond the Ft/Lbs of energy a round will produce.

Theres alot of other variables, id like to see the difference of spire point, flat point, hollowpoint, steel core, exposed lead, projectiles etc...

Mostly to see if surplus steel ammo will dump all its energy into a target or just punch clean through, and if it does punch through, how much force of the impact the target receives.

Also be interested in how big the difference is, i have a sneaky suspicion that the difference isnt that major.

[SixPointEight]

Wolfie, I've seen BOT's stuff, and it's not as scientific as I'd like. I'm hoping to come up with some sort of unit of measure like Nm/in or something.

Whiterabbit, I'm planning on using a very tall column of gel to prevent that.

I'm aware that energy transfer isn't the be-all, end-all of SD/HD, but you have to admit it's pretty important or we'd all use .22lr pistols.

The problem is you're going to use enough gel to completely stop a bullet? Well then it's going to transfer 100% of it's energy. Might as well just calculate the energy (1/2*m*V^2) with a chrono, and get the channel depth from a gel test.

Sounds like a waste to me, but do what makes you happy.

[AragornElessar86]

The problem is you're going to use enough gel to completely stop a bullet? Well then it's going to transfer 100% of it's energy. Might as well just calculate the energy (1/2*m*V^2) with a chrono, and get the channel depth from a gel test.

Sounds like a waste to me, but do what makes you happy.

Yeah, looks like I'll not be measuring the force but instead run a calculation using the mfg stated velocities and projectile weights.

Still gonna have to shoot up a lotta ballistic gel though.

[bear308]

And don't go cheap on the gel, new block for every shot. Like so many things, penetration resistance and expansion cavities change the more times you put something into it.

[perpetual otter]

And don't go cheap on the gel, new block for every shot. Like so many things, penetration resistance and expansion cavities change the more times you put something into it.

Gold.

[M27]

I don't think you need to do a test and all I think it could be done with an equation

stoping power comes down to energy transfer

this equation for energy will give you the energy of projectile at a given distance



then you need to take the answer of that and plug it into another equation that calculates for ballistic coefficient and penetration depth vs depth of target.

[slo5oh]

Sounds like fun to me. I think youll just end up with a load of info that doesnt translate too well into real world scenarios. When the SHTF you can't know for sure what round will serve you best until after the fact. Will be fun to see your results though.

[Cowboy T]

My buddy made some gel and we shot it up at the desert. It was very fun. We tried a variety of SD rounds. The funny part was the only round that went clear through the 18" of gel was a 22 shot out of a 4" Walther. The gel stopped all the larger rounds.

After we were done experimenting we shot it with a 308. It blew the whole block apart into a thousand pieces.

Fun time.

You said it, XDRoX. As the Box O' Truth folks have said many times, "pistols are pistols and rifles are rifles."

http://www.theboxotruth.com/docs/bot16_5.htm

http://www.theboxotruth.com/docs/bot6.htm

Hard to argue with these results.