Two-Projectile Loads in Snubby for Self-Defense

[pettypace]

RC46: Thanks for posting the info on the "Quad Load." Over a year ago, a buddy brought a couple of those to Snubbyfest and I fired one into some Clear Ballistic gel. (page 6, post #114 of this thread). Here's the picture:

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The Quad Load entered from the left and dropped one projectile off at about 10" high in the first brick. The remaining three stopped in a cluster at about 14-15" mid-height in the second brick. Note that there is really only one wound path and that 15" in my C-B gel probably corresponds to only about 12" in real 10% ordnance gel. It seems likely that the nested design inhibits separation of the bullets. But projectile separation is whole point, isn't it? Unfortunately, if they did separate, the little hollow-base conical bullets wouldn't penetrate very deep because the conical shape in not a good penetrator and a 50 grain .35 caliber bullet doesn't have enough sectional density. A quick calculation using the "Expedient Equation" from Quantiative Ammunition Selection shows that even at 1400 f/s that bullet wouldn't meet the 12" minimum FBI standard.

All this brings up an important point: Multi-projectile loads don't enjoy a very good reputation -- perhaps especially among the more experienced shooters. For example, this thread wasn't four hours old before a very knowledgeable shooter declared the whole concept of a two-projectile load for self-defense to be "a loser on every level" that had been "previously rejected (repeatedly) ."

That sort of closed-mindedness is unfortunate because it prevents some shooters with much to offer from making any positive contribution at all. The good news is that most castboolit guys are more open-minded and less dogmatic.

[owejia]

Pettypace good to see you're still pursuing the snubbie fest. Got sidetracked into making 9mm shotshell loads for my 9mm charter arms revolver. Haven't tried to develop any defensive loads for it yet. Charter arms also makes the revolver in .380 I am trying to finding one of those also. The manstopper you were discussing in a previous post in 38 special should be no problem. The Brits used a 200 gr bullet in their 38 S&W crtge revolvers. There were a lot of lives taken with that round in the war. Friend has his grandfathers Webley 455 MarkVI and wanted to shoot it. The cylinder had been shaved for the 45 acp moon clips. The barrel slugged .452 so the 230 gr lrn pc boolits work very well in it. Loaded down to 10-12 thousand cups pressure. They are only proofed to 6 tons. Have had a Enfield 38-200 top break sitting in a gun safe, so time to finally load and try it out. Have been busy casting with the NOE 364-200 gr mould made especially for these old top breaks. The first cylinder of loads thru it at 30 ft, 4 were in a 3" circle shooting off hand. The barrel slugged .3635 so the pc boolits were sized to .364. Spurless hammer so da only with 74 year old arthritic trigger finger, really heavy trigger pull. Have been casting and loading a few hundred rounds for it the last couple of days. Will have some of the 200 gr boolits sized down to .358 and will try then in my snubbie, hopefully before to long. My double round ball loads are what is in my S&W j frame snubbie night stand and carry gun. Hope to try some of the pc round balls in the 9mm revolver. Some of the British top breaks were short barreled in the 38-200 for tank crews. Will continue to follow your progress.

[pettypace]

Good to hear from you, Owejia. Thanks for the update. PM incoming.

[pettypace]

My double round ball loads are what is in my S&W j frame snubbie night stand and carry gun.

Owejia's double round ball nightstand load is what first got me interested in this two-projectile project. In Brassfetcher's gelatin testing (http://www.brassfetcher.com/Handguns/38%20Special/38%20Special%20Ammo%20Selection.html) the old Remington Multiball Load and the Federal Gold Medal Wadcutters out-performed all the premium JHPs he tested from a 2" barrel. Here's the data from those two loads:

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The two loads are virtually equal in penetration. The wadcutter has maybe a 25% advantage in wound mass. But the two round balls have about a 50% advantage in deposited energy. Recoil only slightly favors the wadcutter (PF of 98 vs 112 for the multiball). Certainly target accuracy would favor the wadcutter, but I doubt there'd by any significant difference in combat accuracy from a 2" barrel. Undoubtedly, the wadcutter would do better against bone, but the multiball has the advantage of two wound paths to either miss bone or hit something vital.

All things considered, the two loads look pretty equal to me. Yet the wadcutter load is widely considered an excellent (if not the best) choice for a snubby while the multiball load would be laughed off the pistolero-forum as a bad joke. What am I missing?

[Low Budget Shooter]

If I have processed correctly the many anecdotes I have read, the wadcutter from a snubby, going about 650 fps, penetrates gel or flesh just fine, but does not break and penetrate bone, and so has often disappointed its users by leaving the target evil-doer only minimally injured.

[35remington]

I’ve never been able to find that that is so going over reports of its use. I can tell you from using it on deer for finishing shots that a wadcutter from a snubby pierces bone quite well.

The deer expired quickly from the shot. No bone, whether neck or skull, survived intact and was pierced easily.

[pettypace]

I’ve never been able to find that that is so going over reports of its use. I can tell you from using it on deer for finishing shots that a wadcutter from a snubby pierces bone quite well.

The deer expired quickly from the shot. No bone, whether neck or skull, survived intact and was pierced easily.

I'm not surprised. The wound ballistics guys, Fackler, et al., certainly understood that the vitals were well protected by bone when they came up with the 12" - 18" penetration standard.

[pettypace]

Have you taken a look at this triple conical projectile concept, pettypace?

https://www.scribd.com/document/51462820/Tri-Plex-Multi-Projectile-38-Spl-Cartridge

Predictions by the m-THOR algorithm and Q-model for a 0.3565'' 52.7-grain conical point projectile at 680 fps yield maximum penetration depths of 7.25'' and 9.73'', respectively, with the Q-model best matching the test data produced by John Ervin, Mech.Eng., of BrassFetcher. Deviating the most from Ervin's test data, the MacPherson model under-predicts a maximum penetration depth of just 6.75''.

The fact that multiple projectile loads separate/disperse in flight is simultaneously a strength (in that it increases the number of wound channels and the likelihood of striking a vital organ) and a liability (in that their separation is inconsistent and highly variable and may lead to a munition striking an unintended target). At 15 — 21 yards, the data reflects ''in-flight'' inconsistent separation and dispersion of the projectiles which varies widely from 0.697'' — 4.044''. Given the dynamic nature of gunfights, and the fact that the ability to place shots as precisely as we'd like disappears under stress, such a wide range of projectile dispersion (which is unpredictable, even from the same gun) makes this quality an issue for those considering multi-projectile loads for self-defense.

If I had seen the Tri-Plex Multi-Projectile .38 Special before, then I must have forgotten about it. But looking it over, now, it's probably best forgotten:

If the three bullets separate as intended, then penetration, as you noted, doesn't come close to meeting the FBI 12" minimum requirement. There's a lot of mumbo-jumbo in the write up about "ballistic wound channel" exceeding something or other. But using an optimistic 10" of penetration and calculating wound mass as per MacPherson's WTI model, I get a total wound mass for the three bullets of about 12 grams. Yikes! That's about half of what a single target wadcutter would produce with less recoil and better accuracy. You couldn't run fast enough to give me that tri-plex ammo!

As for accuracy and dispersion, I'm sure some multi-projectile loads are better than others. But having fired hundreds of homemade two-projectile loads in the last couple of years, I've never seen any indication that unpredictable dispersion might be a danger to innocents. Of course, some dispersion is intended and at longer ranges could be problematic -- but not at the ranges I would consider likely for civilian self-defense.

For example, here's a recent 5-shot, two-projectile target I fired about as fast as I could establish sight alignment -- fast enough so that one of the fired rounds went "full auto" (by which I mean that I got rude with the trigger and let one shot off before recovering from recoil of the previous shot).

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The target shows that dispersion due to human error will likely exceed dispersion intrinsic to a two-projectile load.

Consider also this quote from "DocGKR" on the pistol-forum: (https://pistol-forum.com/showthread.php?4331-The-Presumptive-Hazards-of-Over-Penetration)

"Given that the reported averages for LE officers actually hitting the suspect ranges between 12% to 49% of shots fired, more concern should be given to the between 51-88% of shots fired by LE officers which completely MISS the intended target and immediately result in a significant threat to any person down range..."

[pettypace]

In the very first post of this long thread, I wrote something about trying to get wadcutters from a two-projectile load to reliably penetrate 15 inches. Turns out that was a fool's errand on which this fool wasted a lot of time. The charts below illustrate the futility of the effort:

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Considering that any two-projectile load from a snubby is bound to use light for caliber bullets, it's clear that wadcutters are not the best choice. Hence my current interest in the "as-cast mushroom" bullet shape.

Note that the graphs show approximate predicted penetrations in 10% ordnance gel roughly based on the models of Duncan MacPherson (in Bullet Penetration) and Charles Schwartz (in Quantitative Ammunition Selection). The wound mass numbers are calculated using the MacPherson's WTI (wound trauma incapacitation) model which may be considered the "effective" wound mass. The wound mass per inch of penetration column is just to satisfy my curiosity.

[pettypace]

I don't think you're foolish at all. You wanted to learn and the journey led you here. Now you know more than when you started!

Some folks seem unable to capitalize on experience. You do not.

If you are seeking the most efficient penetrator (per unit of projectile mass) in the pursuit of optimizing a prospective load, may I respectfully suggest the truncated cone flat point profile—

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—as the most promising candidate?

Thanks, Chuck. But you can't win an argument about how foolish I can be... I have much more data. ;)

I certainly agree with you on the penetration of the truncated cone. Using a TC for the front bullet of a two-projectile load makes a lot of sense. Even at 100 grains and just 625 f/s, it pushes the far end of the FBI penetration requirement and it's speedloader-friendly to boot. Way back in post #108 (page 6) I mentioned the little Lee TL356-95-RF bullet sailing through 22" of C-B gel, making a 1/4" deep dent in a pressure-treated plank well behind the gel blocks, and bouncing back to whack in the ankle a shooting buddy standing well behind the firing line. It didn't draw blood but it did change our range safety practices.

But I've not been impressed with a TC or RF for the rear bullet where the nose is unpredictably distorted on firing. So, right now I'm more interested in this design:

270708

Just as a little Gedankenexperiment, suppose that 110 grain Nosler had been fired into a long block of 10% gelatin and had expanded to just 35 caliber. What would be the length of the last 600 f/s of wound track?

[pettypace]

I am always up for a good Gedankenerfahrung, so...


Thanks for the number-crunching, Chuck. But let's continue with the Gedankenerfahrung...

Suppose that projectile had started out life with that same .35 caliber diameter and that same "expanded JHP" shape and had somehow been projected into a fresh block of 10% gelatin with a velocity of 600 f/s. What would be the predicted penetration distance then?

[Good Cheer]

If this was 1980 I didn't let my favorite gunsmith talk me out of straight cylindrical bored chambers and 30-30 brass trimmed to length and formed to suit then I could probably tell you all about the multiple projectile souper-dooper. But he did talk me out of it and dad gummit now I'd still like to tinker with it. Oh well. So much stuff and too little decades.
:)

[pettypace]

I finally got around to writing the "Monte Carlo simulation" suggested by The_Schwartz way back on page 12 (post #223). There's a link to the program below. But first a warning...

WARNING: The link below will run a homemade program on a remote server. Although I've taken some modest precautions to secure the program, there's a small but finite possibility that a hacker somewhere between Azerbaijan and Zimbabwe will have already figured out a way to use the program to inject malicious code into your computer to download all your personal information and empty your bank accounts. If this worries you, DON'T CLICK THIS LINK (http://snubbyfest.000webhostapp.com/twoskunks.php?SDa=1&DDa=0&Na=100&SDb=2&DDb=1&Nb=100).

If you were brave (or foolish) enough to actually click that link, then you've already seen something like this:

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The target on the left shows the simulated results of firing 100 shots with a conventional single-projectile load with a standard deviation of 1". The target on the right is a simulation of firing 100 shots of a two-projectile load with a standard deviation of 2" for the first projectile and a second projectile that strikes with a standard deviation of 1" from the location of the first shot. The program prints the input data as well as the number of "vital hits" at the top of each target. In the picture above, the conventional "simplex" load scored a total of 69 vital hits while the crazy "duplex" scored 78 vital hits. Of course, these numbers change each time the program is run.

[bluelund79]

I use a triple load inside of a Speer capsule. I use 1 .283 ball below 2 .300 from track of the Wolf. At 15 yards, the (2) 300 balls hit POA/POI with the fixed sights of my 442 airweight, and the 283 ball hits about 2” lower. It’s a fun one, and reasonably economical to shoot a cylinder worth at the range to remember my sight picture. I’ve been lucky enough to have it be reliable for a full rounds worth too. I use Unique powder to set it off.

[pettypace]

Damn you, pettypace. :killingpc



I'm glad you like the simulator, Charles. It was, after all, at your suggestion. But I figure I still have a long way to go to re-pay you for Quantitative Ammunition Selection.

[The Schwartz]

I'm glad you like the simulator, Charles. It was, after all, at your suggestion. But I figure I still have a long way to go to re-pay you for Quantitative Ammunition Selection.

You just did, friend. :wink:

Merry Christmas, pettypace.

One of these days, I gotta learn to write code like that. Awesome skills you have there and a very professionally executed product. Color me with :mrgreen: with envy and admiration.