https://youtu.be/Eu9RHE0OZRU

A few weeks ago, I made a video for the AR15.com YouTube channel comparing real ballistic gelatin to clear gel. It's not uncommon to see folks using water jugs and other, affordable options to roughly gauge ammunition performance, so I fired a round of the same Nosler 64 gr bonded soft point through a row of water jugs to see how differently it penetrates in water (and thin layers of HDPE). I think it might be fun to map out a relationship between water and 10% gelatin for penetration. If anyone is willing to participate, we could take any load that is already documented in 10% gelatin and fire it through water to see how penetration compares. I suspect that the relationship is not linear, and the ratio changes with velocity.

iirc, the penetration ratio is 1:4 (water:gel)



it might be better to use quart sized cardboard drink containers to get a finer measurement of water penetration.  i think they are about 4" across

I don't believe it to be linear.

i'm not sure.  I know there were some discussions about this over at Lightfighter about 10 years ago that Doc Roberts was involved in and the thing that sticks in my head is 1:4



 

Well, this was four jugs for a total of 24" of water. The same round penetrated 15" of 10% ordnance gelatin. If it were 1:4, water to gel, the expected gel measurement would be 96". If it was the reverse, we would expect to see 6". If I recall correctly, Dr. Roberts has said that a ratio of about 1:1.6 - 1:1.8 gel to water can be expected. That fits perfectly with this test. (15" x 1.6 = 24") but I suspect that the ratio may change as velocity and bullet construction varies. I would imagine that it's still close to the ratio that Dr. Roberts gave, but I think the slight curve to the relationship is the reason that he gave a range of a factor of 0.2.

I plan to do exactly that. Or maybe phone books.

It has been discussed by Dr Roberts and other ballisticians, and it is indeed a corollary, however, HP's tend to over-expand in water. A good rule of thumb is that a HP that sucks in water, is a complete failure at life. A HP that works great in water, may or may not work great in gel or people or animals. Further evaluation is needed.

Also take into account that you are going through how many layers of plastic? The skin on one's back is equivalent to several inches of 10% gel. How many inches is 3-5 milk-jug skins equal to? I'd say it's significant for an expanded projectile.

Yeah, I'm not sure. You would expect the plastic to have a substantial effect, but the measurement here was consistent with Dr. Roberts' figure. I suspect that the plastic accounts for a lot less than the water that it contains. It's important to remember that the resistance that water offers is a result of the mass that must be moved, not its shear strength. Obviously, water has virtually zero shear strength while the HDPE has significant shear strength. I think Old_Painless' BOT is a more accurate way to measure water penetration because it allows the use of smaller increments of water (2"-3" thick bags, instead of 6" thick jugs) and the thinner LDPE is less substantial.

nice looking little bullet after that water test. soft points have made the choo-choo-tree round a great SD round for such a small caliber.

It worked well in gelatin, too.

I will say, I've often found bullets shot into jugs have heavily dented the far fall on the last jug, or almost made it through it, etc. So I know it's limiting them, I'd assume the other jug walls do, too. I honestly don't know how much it matters.

I've shot a lot of various plastic jugs filled with water over the years and recovered numerous projectiles.  I found the gallon jugs used commonly for milk or juice stay in place better than the 2 liter pop bottles.  The better performing pistol bullets tend to stop in the 3rd or 4th jug.  These recovered bullets appearance is very similar to pistol bullets recovered from deer.

I've shot several  deer which had been injured in motor vehicle collisions with pistols.  Most of these deer were recovered and used by local residents either for food or to feed their dogs.  Several people were able to recover bullets and were returned to me.   Most of the deer I put down were with head shots with different caliber pistols I carried as a LEO.  

I have recovered 357 magnum 125 grain JHP's, 357 Magnum 145 grain Silvertip, WW 9 MM 115 grain JHP +P+, 200 grain Speer/CCI JHP "flying ash tray" and 45 ACP 185 grain Silvertip.   The bullets used on deer head shots exhibited expansion similat to those bullets I recovered from being shot into jugs of water.  The bullets recovered from deer exhibited tearing or gouges in the bullets from striking hard bone.  


The deer shot with high velocity pistol bullets like the 125 grain 357 Magnum out of a 4" in barrel, 9 MM 115 grain JHP +P+ and 135 grain 40 S&W JHP were very effective and immediately dispatched the deer.  The slower heavier 45 ACP 185 grain and 180 grain 40 S&W did not seem as effective.  The one 45 ACP bullet which was very effective was the 200 grain Speer/CCI "flying Ash tray".  I shot this bullet out of a 3.5" Detonic, 4.25" Combat Commander and this bullet caused the same reaction in deer as the lighter faster bullets.  

The better pistol bullets I tested in water were usually captured in the 3rd or 4th jug.  The 223/5.56 55 grain FMJ usually fragments at the cannelure and stops in the 3rd jug but beyond 70-100 yards the bullet appears to flatten at the base and basically stays intact and will penetrate deeper.   I felt shooting into water was a practical way to compare bullets performance equally.  

A lot of my water testing was done in the late 70's to early 80's when JHP and JSP were just being adopted by LE.  For you old guys we even tested the Super Vel JHP bullets which were probably the first pistol JHP bullets.   There can be significant difference in bullet performance but shot placement is the most critical component IMHO.

Yeah, a great bullet won't make up for bad shot placement but almost any bullet that gets deep enough will get the job done if you put it in the right spot.

SWIFT bullet company uses water when they develop their projectiles, and they have been rather successful at making good projectiles that perform very well in the real world.

I'd bet that if you make a bullet that will expand at low velocity in water and hold together at high velocity in water, it will do really well in field conditions.

Yep. Especially if it's a soft-point, water makes JHP's look like a rock-star at lower velocities.

what would that jacket be made out of? or maybe just a thinner jacket? guess that might posse problems with higher velocity.

is the lead in normal jacketed bullets 100% lead or do they blend it like the hard cast pistol bullets?

My memory is hazy, but I think I recall reading some where years ago that water was typically 1.75 to gelatin.  Which is in the range described earlier.

I shot a lot of OJ cartons years ago.  With what most people would consider good JHP handgun rounds, performance was very similar, penetration wise, though some bullets splashed a lot more water than others.

Water is very consistent, wet newspaper is not.  

I would have to go upstairs to check, but I believe Duncan McPherson's book discusses water penetration compared to gelatin penetration.  I have another book which I know does.

I would consider water to be a valid test medium.  Not as good as gelatin, but much, much cheaper, and easier.

Certainly water is good enough for quick & dirty testing.

Water can do strange things to bullets.  I remember firing 7.62 x 51 FMJ into OJ cartons at 12 feet.  The bullet was recovered from the 3rd carton.  Won't do it all the time, but it did it once.

My State's crime lab uses a water tank to capture projectiles for ballistic comparisons.  Their tank has an angled tube for shooting the firearm into the tank.  I don't remember the size of the tank or how many gallons it held but they are able to use the tank to capture rifle bullets.  If I remember correctly they have a sreen which sets on the floor of the tank.  After firing they open the lid of the tank and raise the screen to retrieve the bullet and/or fragments.  

The 125 grain 357 magnum JHP bullets shed a lot of wight even if shot out of 2.5"-4" barrels.  The bullets recovered from dear had lost most of their 125 grain weight with just the base and core intact.  The mushroom had sheered off but this JHP at 357 magnum velocity was usually an effective bullet in revolvers when carried by LE.  The bullets I recovered from water exhibited the same type of expansion in water as in deer, whether 357, 9 MM, 40 or 45.  

I also compared bullets shot into water from different barrel lengths.  We shot 45 ACP out of 3.5", 4.25", 5", 7" (AMT Hard baller Long slide IIRC) and 16" carbine.  We also tested the 38/357 out of 2", 2.5", 4", 6" 8 3/8" and 16" barrels.  The 9 MM was tested in 3.5", 4", 4.25", 5" and 16" barrels.   My shooting partners and I also shot different projectiles through car doors and automotive glass.  We discussed submitting our results to gun magazines but raising families the data never got submitted.

Sorry for the thread hijack.  

Like Hornady's SST line.

Has a thin jacket up front so it expands at low/fast velocities and a inner banded core to keep the jacket together for penetration.

Best of both worlds.

Interesting thread, I had some gel test done a few weeks ago and then tested same bullets in water using gallon ziplocks instead of gallon jugs.
I did the math and wrote down my unscientific formula, but it's in my notes at home, seems it is pretty close to what you tested.
Thanks for posting this, I will check what I have in my notes this evening, I still have some more bag testing to do.
I modified 2 plastic storage containers so you can line up the ziplocks.

That's a cool design!

My videos are short and sweet, just started playing around, don't judge it too harshly, I also suck at editing, using an ipad mini to video.


I got the storage bins at Lowes, tried to size em for 1 gallon bags.


Cheaper than jugs and as I'm sure you know cleaning up 15-20 gallon jugs and packing em out sucks.









 
 

Nice! I subscribed and shared your video on Facebook.

If you have a PC, you may consider using Windows Movie Maker. It's pretty easy. As you grow, you'll probably transition into other software, but Movie Maker isn't bad at all. Email me at [email protected] if you have any questions about editing or whatnot.

Thanks,I appreciate it.


 

LOL, it was Doc Roberts who came up with it, anyway.