Two-Projectile Loads in Snubby for Self-Defense

[owejia]

Pettypace , are you still experimenting with the snubbie fest? Have you tried a 9mm snubbie in any of your experiments? Picked up a 9mm Luger Pit Bull and am just starting to work up some loads for it. Not much information out there for 9mm in a snubbie.

[pettypace]

By now, my Clear Ballistic gel has been melted and re-melted so many times that its color pretty well matches the OD of the ammo cans I'm using for brick moulds. At this point it's not worth trying to take photos (although a video of a blast from a buddy's .401 Winchester Self-Loader might have been entertaining.) But even though the gello is pretty nasty, it still stops bullets and there's still something to be learned.

NOTE: Penetration in Clear Ballistic gel does not compare inch-for-inch with penetration in 10% ordnance gel. What "looks good" in C-B gel will not look nearly as good in the real gelatin.

At Wednesday's Snubbyfest, the first shot into the gel was from the aforementioned .401 WSL. The ammo was a 200 grain soft point out of a green Remingon box. The chrono read 2380 ft/s (IIRC). Although the bullet lifted both gel blocks high in the air and onto the ground, it only penetrated about 13" and broke into lots of pieces with only about 150 grains making it to the final resting point. Plenty of energy and a poor bullet.

Next up was a Speer Short Barrel Gold Dot .38 Special +P fired from a S&W 640 snubby. This guy landed at 13" right next to the rubble from the .401 WSL. The bullet expanded to about 0.55". Unfortunately, the chrono balked on this one and no velocity was recorded. From other testing I've seen online, it was likely about 850 ft/s.

Finally, I fired 5 rounds of a .38 Special two-projectile load from the same S&W 640. The load was two 110 grain hard-cast WCs stacked base-to-base over an ample charge of 2400. Average chronographed velocity: 735 ft/s. (NOTE: This is certainly a +P load and should be reduced.) Forgetting that the heavy payload shoots high, the back bullet of my first shot escaped out the top of the first gel block. The other nine projectiles were captured in the gel at 13.5, 16, 16, 17, 17.5, 18, 18.5, 19, and 19 inches. Average: 17.6". Assuming the previously determined calibration factor of 0.81 is still valid, that would give an average penetration in 10% gel of approximately 17.6 * 0.81 = 14.3".

[pettypace]

Pettypace , are you still experimenting with the snubbie fest? Have you tried a 9mm snubbie in any of your experiments? Picked up a 9mm Luger Pit Bull and am just starting to work up some loads for it. Not much information out there for 9mm in a snubbie.

No. The only 9mm that has shown up at Snubbyfest was a pristine Lahti. And the owner only had hardball. Not enough gello to stop that.

I'm jealous! Wish I could have a 9mm Pit Bull. But they're not "Mass Compliant."

Finding a defense load for a 9mm snubby sounds like an interesting problem. I don't see how you could beat a good 147 grain JHP. But that assumes reliable expansion at whatever velocity you get from the Pit Bull. If you have a place for testing, you could shoot through a half-gallon milk carton of water and catch the bullet in a trash bag full of pillow stuffing. That should give you the expanded diameter. Then the "expedient equation" from Quantitative Ammunition Selection will give you predicted penetration and wound mass. Once you find a reliable JHP to carry, just match a cast boolit load to it for practice -- maybe something like NOE's 358-155 TC. And I'd put a DAO hammer on the Pit Bull if it were mine.

[pettypace]

Here's a novel idea, maybe best illustrated with a "thought experiment:"

Suppose you want to turn your .38 snubby into a classic "manstopper" for civilian self-defense. Your first try might be your granddad's .38 Special Super Police load. According to Hatcher in 1935, that load could launch a 200 grain round-nose bullet at 623 f/s from a 2" barrel. But is it a manstopper? Well, if the bullet goes in a straight line, terminal ballistics should look like this:

Attachment 270006

What's of interest here? Well, the load is probably within standard SAAMI pressure limits and won't blow up your snubby. But with a power factor of 125, it will be handful from an alloy J-frame. On the other hand, Keith once said of heavy loads from a snubby that "any man would rather have a sore hand than a hole in his belly." But is the Super Police load a "manstopper?" Well, it certainly has enough penetration to reach vital structures and with fortuitous shot placement, that should be enough. But you could say the same for a .380 FMJ round. And if no vital structure is hit, the 16 grams of wound mass from the Super Police load is no more than we'd expect from a .380 FMJ.

Let's put aside for now the fact that the Super Police load very likely "tumbles" and is probably more effective than I'm giving it credit for. There's another way to improve the Super Police load. Suppose we just change the 200 grain round nose bullet for a 200 grain wadcutter. Here's how that looks:

Attachment 270007

That's better. We still have more penetration than the law (or, at least, the FBI) allows. But simply by changing the nose shape of the bullet, we increased wound mass by over 50%. That's a significant increase. But a standard .38 Special target wadcutter produces as much wound mass with significantly less recoil. Many folks consider the target wadcutter the best load for a light weight snubby. To improve on that, we need either to go over to the dark side or to try something radical...

So, what if we cut that 200 grain wadcutter in half to make two stubby little 100 grain wadcutters. We load both little wadcutters into the case, carefully adjusting the powder charge to maintain the same 623 f/s. Here's the terminal ballistics for just one of those projectiles:

Attachment 270008

Note that each of the 100 grain wadcutters crushes the same 16 grams as the original 200 grain Super Police load. In fact, the total of 32 grams for the two wadcutters is just shy of the 34 grams MacPherson cites for the maximum wound mass from a 9mm/.38 cal JHP. More importantly, each of those little wadcutters cuts it's own separate path through the tissue, increasing the probability that a vital structure will be hit by one or the other. Of course, that assumes the short wadcutters have adequate penetration to reach the vital structures. According to the graphs (based on MacPherson's penetration model ) the little wadcutters should penetrate about 12" in 10% ordnance gel. The FBI considers 12" adequate. But if the little wadcutters average 12" of penetration, about half of them will penetrate less than 12". Maybe the increased probability of hitting a vital structure will be outweighed by the decreased probability of penetrating deep enough to reach a vital structure. So, what's to be done?

Well, here's the novel idea: Suppose we just change the nose shape of the stubby little wadcutters to match the shape of an expanded JHP -- into something I'm calling an "As-Cast Mushroom" or ACM for short. Here's the terminal ballistics info for just one of those two 100 grain .35 caliber ACM at 623 f/s:

Attachment 270009

Now, we have two separate projectiles, each penetrating to 17" along separate wound paths with a greatly increased probability of hitting a vital structure and a total combined wound mass of 38 grams. We'd be hard-pressed to find a .38 Special load with more right to be called a "manstopper."

Of course, it seems a little far-fetched that we can magically gain 5" of penetration and 3 grams of wound mass by somehow changing a wadcutter into the shape of an expanded JHP. But that's what the penetration models of both MacPherson (in Bullet Penetration) and Schwartz (in Quantitative Ammunition Selection) suggest and my initial testing seems to verify that suggestion. More on that later.

[megasupermagnum]

Here's a novel idea, maybe best illustrated with a "thought experiment:"

Suppose you want to turn your .38 snubby into a classic "manstopper" for civilian self-defense. Your first try might be your granddad's .38 Special Super Police load. According to Hatcher in 1935, that load could launch a 200 grain round-nose bullet at 623 f/s from a 2" barrel. But is it a manstopper? Well, if the bullet goes in a straight line, terminal ballistics should look like this:

Attachment 270006

What's of interest here? Well, the load is probably within standard SAAMI pressure limits and won't blow up your snubby. But with a power factor of 125, it will be handful from an alloy J-frame. On the other hand, Keith once said of heavy loads from a snubby that "any man would rather have a sore hand than a hole in his belly." But is the Super Police load a "manstopper?" Well, it certainly has enough penetration to reach vital structures and with fortuitous shot placement, that should be enough. But you could say the same for a .380 FMJ round. And if no vital structure is hit, the 16 grams of wound mass from the Super Police load is no more than we'd expect from a .380 FMJ.

Let's put aside for now the fact that the Super Police load very likely "tumbles" and is probably more effective than I'm giving it credit for. There's another way to improve the Super Police load. Suppose we just change the 200 grain round nose bullet for a 200 grain wadcutter. Here's how that looks:

Attachment 270007

That's better. We still have more penetration than the law (or, at least, the FBI) allows. But simply by changing the nose shape of the bullet, we increased wound mass by over 50%. That's a significant increase. But a standard .38 Special target wadcutter produces as much wound mass with significantly less recoil. Many folks consider the target wadcutter the best load for a light weight snubby. To improve on that, we need either to go over to the dark side or to try something radical...

So, what if we cut that 200 grain wadcutter in half to make two stubby little 100 grain wadcutters. We load both little wadcutters into the case, carefully adjusting the powder charge to maintain the same 623 f/s. Here's the terminal ballistics for just one of those projectiles:

Attachment 270008

Note that each of the 100 grain wadcutters crushes the same 16 grams as the original 200 grain Super Police load. In fact, the total of 32 grams for the two wadcutters is just shy of the 34 grams MacPherson cites for the maximum wound mass from a 9mm/.38 cal JHP. More importantly, each of those little wadcutters cuts it's own separate path through the tissue, increasing the probability that a vital structure will be hit by one or the other. Of course, that assumes the short wadcutters have adequate penetration to reach the vital structures. According to the graphs (based on MacPherson's penetration model ) the little wadcutters should penetrate about 12" in 10% ordnance gel. The FBI considers 12" adequate. But if the little wadcutters average 12" of penetration, about half of them will penetrate less than 12". Maybe the increased probability of hitting a vital structure will be outweighed by the decreased probability of penetrating deep enough to reach a vital structure. So, what's to be done?

Well, here's the novel idea: Suppose we just change the nose shape of the stubby little wadcutters to match the shape of an expanded JHP -- into something I'm calling an "As-Cast Mushroom" or ACM for short. Here's the terminal ballistics info for just one of those two 100 grain .35 caliber ACM at 623 f/s:

Attachment 270009

Now, we have two separate projectiles, each penetrating to 17" along separate wound paths with a greatly increased probability of hitting a vital structure and a total combined wound mass of 38 grams. We'd be hard-pressed to find a .38 Special load with more right to be called a "manstopper."

Of course, it seems a little far-fetched that we can magically gain 5" of penetration and 3 grams of wound mass by somehow changing a wadcutter into the shape of an expanded JHP. But that's what the penetration models of both MacPherson (in Bullet Penetration) and Schwartz (in Quantitative Ammunition Selection) suggest and my initial testing seems to verify that suggestion. More on that later.

The only problem I see with this plan, is either the bullets would have to be concave base, or the bottom one would likely leave the barrel as a wadcutter anyway.

[pettypace]

The only problem I see with this plan, is either the bullets would have to be concave base, or the bottom one would likely leave the barrel as a wadcutter anyway.

You're right! The back bullets do get squashed a bit. But they're still "rounder" and penetrate significantly deeper than a real, flat-nose, sharp-shouldered wadcutter. I haven't paid enough attention to learn if there's any significant difference in penetration between the front and back bullets. But there certainly is a difference in penetration between the as-cast mushrooms and a wadcutter.

Here's a picture of a couple 80 grainers -- back bullet on the left and front on the right.

Attachment 270049

The extra penetration of the as-cast mushroom opens the possibility of lighter loads, say two 80 grainers, that will still give adequate penetration but have less recoil and less difference between POA and POI.

[Kosh75287]

If I've brought this up before, please forgive my failing memory. There used to be a gimmick round called a "Quadcutter", which was 4 77 (ish) gr. wadcutters, redolent of the Lyman #358101 75 gr. "Flying Tuna Can", stuffed into a .357 mag case. I think patterning, low penetration and it not being offered in .38 Special (not to mention Weirdness) led to its eventual disappearance.
Your two-projectile concept makes more sense to me, but I'd still be apprehensive about accuracy. In the stressful conditions of a gunfight, it's easy enough for me to hit the wrong things, if my sidearm launches only one projectile per trigger squeeze. Doubling my odds of that seems like inviting trouble.

[pettypace]

If I've brought this up before, please forgive my failing memory. There used to be a gimmick round called a "Quadcutter", which was 4 77 (ish) gr. wadcutters, redolent of the Lyman #358101 75 gr. "Flying Tuna Can", stuffed into a .357 mag case. I think patterning, low penetration and it not being offered in .38 Special (not to mention Weirdness) led to its eventual disappearance.
Your two-projectile concept makes more sense to me, but I'd still be apprehensive about accuracy. In the stressful conditions of a gunfight, it's easy enough for me to hit the wrong things, if my sidearm launches only one projectile per trigger squeeze. Doubling my odds of that seems like inviting trouble.

Of course, accuracy is a consideration. But despite the mantra that "Shot placement is king and penetration is queen," I decided from the beginning to focus on penetration instead of accuracy. That's partly because the accuracy I was getting without any effort seemed adequate for the purpose of civilian self defense, and partly because I didn't see much sense in trying to improve accuracy of a round that wouldn't penetrate adequately.

Although at this point I'm convinced that "as-cast mushrooms" solve the penetration problem, I'm afraid that work on the project proceeds at, well, a petty pace. I'm anxiously awaiting a 4-barrel mould (two .38s and two .44s) from Tom at Accurate Molds. When the mould arrives and if the weather, my health, covid, and the primer supply all cooperate, I might get around to concentrating more on accuracy.

In the meantime, it's worth seriously considering just what are the accuracy requirements for civilian self defense.

[pettypace]

Here's a picture of a .35 caliber, 105 grain as-cast mushroom next to a 105 grain wadcutter from a shortened H&G #50 mould.

Attachment 270046

And the ACM mould:

Attachment 270047

The test consisted of (A) 5 shots with the HG50 loaded backwards (for calibration), (B) 5 shots with the HG50 loaded forward, and (C) 5 shots with the ACM loaded forward. All bullets were seated flush with the mouth of case over the same 2.8 grains of "vintage" Bullseye. All shots were fired in rotation (A,B,C,A,B,C, etc.) into the same two ammo can size bricks of well-used Clear Ballistics gel. All shots were fired over a chronograph, although some didn't register.

Here are the results:

(A) 105 grain HG50 loaded backwards:
Velocity: (671+624+674)/3 = 656 f/s
Penetration is C-B gel: (16.75+17+17.5+18+17)/5 = 17.25"
Predicted penetration in 10% ordnance gel: 14"
Calibration factor: 0.81 (Note substantial agreement with previous calibration earlier in this thread.)

(B) 105 grain HG50 loaded forward:
Velocity: (655+625+646+656)/4 = 645.5 f/s
Penetration in C-B gel: (16.75+17+21+18.5+19.75)/5 = 18.6"
Penetration calibrated to 10% ordnance gel: 18.6 * 0.81 = 15" (using calibration factor from (A) above)
Predicted penetration in 10% ordnance gel: 14" (So, maybe the button nose gains an inch of penetration?)

(C) 105 grain ACM:
Velocity: (686+675+648+612+676)/5 = 659 f/s
Penetration in C-B gel: 22"+ (One recovered with nose poking out of 2nd gel brick (22"). Others went through and through.)
Predicted penetration in 10% ordnance gel: 19" (Modeled as expanded JHP.) (Translates to over 23" in C-B gel.)

[RC46]

On topic: found this in an old Dean Grennell book.

[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:

Attachment 240947

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 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:

Attachment 270191

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/5146...-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).

Attachment 270308



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:

"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:

Attachment 270487

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—

Attachment 270566

—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:

Attachment 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?