Fragmentation VS Retained Weight

[madmag]

The past months I have been doing a lot of reading and viewing of video tests show results of (pistol) bonded VS non-bonded bullets penetration water jugs, denim, gelatin, etc. When they show the results they imply that the bullets that fragment are not as effective as the bonded bullets that retain 100% of their original weight. But I have noticed some things about the fragmented bullets. They seem to penetrate about as well as the bonded bullets, and the fragmented pieces seem to make it to the final depth of penetration. So, I assume fragmentation occurs toward the end of their travel.

Question: Is fragmentation really an indication of failure? Does bonded mean it's going to be a lot better, or are they closer in doing the job than we think??

 

[demigod]

Fragmentation is desireable when talking rifle bullets in combat. But since pistol bullets are generally a weak compromise to carrying a rifle with us at all times, we generally want a bullet that expands but retains it's full mass for deepest penetration.

Even though a test may show the frags going as far as the main projectile, perhaps the bullet would have penetrated another inch or two if it didn't frag.

 

[madmag]

Even though a test may show the frags going as far as the main projectile, perhaps the bullet would have penetrated another inch or two if it didn't frag.

OK, but there must be a least some collateral damage from the fragments....does that help?

PS. My main reason for researching is I have a lot of older ammo that is not bonded. I use to think it was pretty good, now I am re-thinking.

 

[mete]

Penetration is proportional to mass so the larger the piece the more it penetrates ! Yes the premium 'bonded 'bullets perform better. While small pieces 'might' do damage consistant performance is more important.
When we shoot high velocity bullets we sometimes get 'secondary projectiles' where the bullet hits bone and small pieces of bone can do damage. My most interesting experience with secondary projectiles was butchering a friends deer .He hit the shoulder with a 130 gr .270.I found a small hole in the ham .The bullet projected a small [1/8" ] piece of bone from the shoulder going half way through the thickest part of the ham !!!

Last week I had a flat tire - caused by a 1/2" piece of bone apparently from a road kill - small pieces can be dangerous !

 

[Kreyzhorse]

Question: Is fragmentation really an indication of failure? Does bonded mean it's going to be a lot better, or are they closer in doing the job than we think??

I guess it depends on how bad the bullet frags. I don't think that a few fragments are a bad thing so long as the bullet still penetrates and retains most of its weight.

 

[demigod]

I have some corbon 165 gr 40 s&w ammo that sheds its jacket religeously in water. I quit carrying those rounds. I just pic a nice gold dot or Ranger load and don't obsess on it.

Where you put the bullet will be much more important.

 

[madmag]

I just pic a nice gold dot or Ranger load and don't obsess on it.

I have Gold Dot in all my calibers. I agree they are a great choice. I was just trying to decide if I consider my older HP's (non-bonded) to be just for target practice.


Ok, I know this is a little on the anal side. But what if a same caliber (non-bonded) is a hotter load than a load you have that is bonded. Is the bonded still a better choice?

 

[demigod]

All things equal, I guess bonded is a better choice. I keep my old defensive ammo for mags that I stick in the door pocket of my car or in my brief case, etc.

 

[Jim March]

To understand what happens when a JHP starts to "shed it's nose", you have to look at gelatin shots.

The general pattern is that as the nose falls apart and/or the jacket sheds, the total expansion width drops back down on the main core and the "extra bits" are found dribbled back along the main wound path.

I don't think JHP fragmentation at handgun velocities aids wounding.

My gun is loaded with Gold Dot slugs, the 125gr 357 high speed variety. These tend to retain 100% weight or close to it as the jacket is strongly bonded to the lead core.

Weird thing is, if you look at a real frangible load like the Glaser Silver, the fragments appear to "explode forward" and with some spread along the wound channel, a totally different sort of effect. With enough raw power I think the larger-pellet Glaser Silver might have some usefulness and if my gun was a 44Mag, I'd consider them. With full-house 357 loads, I've decided that the more conventional Gold Dots are the best idea both in terms of wounding and going to the sight's point of aim.

 

[madmag]

Ok, I do have Gold Dot for my first line ammo. Maybe I will just consider some of my older HP's as back-up.

I don't want to turn my own thread into a brand discussion, but I do have some non-bonded ammo that seems to perform well. I have shot quite a lot of Winchester WB 230g HP .45ACP ammo. I know this is not really premium grade, but it functions very well and I have seen several reports and videos that show it to retain weight about as well as any bonded ammo. It does not have that neat petal look, but it doesn't fragment. I understand money is not the main issue for SD, but this ammo just seems to work well. But I have some expensive non-bonded .357 and .38 stuff that is bad for fragmentation.

With enough raw power I think the larger-pellet Glaser Silver might have some usefulness and if my gun was a 44Mag, I'd consider them.

I have tried the Glaser Blue in .38 spl. +P, didn't like them at all. POA was too different and I don't have the money to buy enough for real evaluation.

 

[Webleymkv]

It depends on how deeply the bullet penetrates before fragmenting. The old .357 Magnum 125grn SJHP's from Remington and Federal routinely fragment, but they do so slowly and still penetrate adequately. These loadings have a very good, and well deserved, reputation. Problems with fragmentation come about when you have very light-for-caliber bullets driven at very high velocities. A good example of this is the various 90grn 9mm loadings that were popular for a time. These bullets tended to fragment violently relatively early and thus did not penetrate well.

Also, just because a bullet is not bonded does not necessarily mean that it's likely to fragment. The Winchester Black Talon/SXT is a non-bonded bullet yet it does not seem to have issues with fragmentation and has a well deserved reputation as an excellent performer.

The main issue is that non-bonded bullets have a much narrower velocity window than bonded ones do. Driving a non-bonded bullet too fast is much more likely to produce fragmentation than a bonded one. This is why custom ammo makers like Buffalo Bore and Double Tap prefer bonded bullets. Conversely, non-bonded bullets that are intended to be driven at high velocities often expand less aggressively and may have issues with reliable expansion if driven at lower velocities. A good example of this is the Hornady XTP. While these bullets tend to hold together quite well at relatively high velocities, they often have trouble with reliable expansion in lower velocity loadings such as Hornady's standard pressure 158grn .38 Special loading.

 

[LordTio3]

When they show the results they imply that the bullets that fragment are not as effective as the bonded bullets that retain 100% of their original weight. But I have noticed some things about the fragmented bullets. They seem to penetrate about as well as the bonded bullets, and the fragmented pieces seem to make it to the final depth of penetration. So, I assume fragmentation occurs toward the end of their travel.

Question: Is fragmentation really an indication of failure? Does bonded mean it's going to be a lot better, or are they closer in doing the job than we think??

A failure to what end? I find that when most questions like this get asked, the person asking doesn't completely understand what question they are asking. You asked if, when a round fragments, if it is an indication of failure. The real question is, "And indication of failure to Do What Exactly?" If it is intended to retain it's structure, then yes. But fragmenting rounds are not designed to retain their structure. They are designed to fragment, so to say that they fragment is to say that they perform as they were intended to perform.

What question you should really be asking, in order to understand what you're studying, is "Which variety of projectiles (bonded or fragmenting), once they enter the human body, have a larger propensity to cause debilitating damage?"

So, let's look at it. A single bonded hollow point should typically leave a single cavity with a relatively large wound channel, causing consistent damage to a consistent depth, in a single direction. Fragmenting rounds can cause multiple wound channels, with varying depths, vectors, and damage potential depending on what the round impacts and at what depth the fragmentation takes place.

Conclusively, at the KE and velocity levels that most handguns perform at, the differences in performance is minimal. And as long as both rounds function reliably in the weapon, they could probably be used interchangeably without a noticeable level of performance variation. Surgeons will tell you that it is much more difficult to remove several pieces of a single round and stop internal bleeding from multiple smaller wounds than from a single wound channel, but during the course of fire in the precious seconds of a gun-fight, what his surgeon is going to think in 45 minutes is quite irrelevant.

~LT

 

[madmag]

They are designed to fragment, so to say that they fragment is to say that they perform as they were intended to perform.

My question was not about ammo that is designed to fragment, it was about ammo that is non-bonded (intended to maintain structurer) and happens to fragment.

What question you should really be asking, in order to understand what you're studying, is "Which variety of projectiles (bonded or fragmenting), once they enter the human body, have a larger propensity to cause debilitating damage?"

Thought that's what I asked, just with a shorter non fancy sentence.

Does bonded mean it's going to be a lot better, or are they closer in doing the job than we think??

 

[MikeNice81]

Another question you have to ask is, do the test corelate to real life? If somebody is shooting in to water they usually get the absolute maximum expansion. In a non bonded bullet this could be fragmentation. If they are shooting in to gel it is more like shooting through flesh.

Either way I would not be overly concerned about fragmentation. I would be more worried about faliure to expand. The Hornady XTP is a great example. The bullet performs great when it reaches certain velocities. However, in the .380 load they have trouble expanding from a Kel Tec sized gun. Yet their 124gr 9x19 load performs excellently in a Kel Tec PF-9. My point is, make sure you are achieving the velocity to make them work.

My overall feeling is that bonded are great if you need to shoot through a barrier. I believe they offer a real advantage in such a situation. However, when it comes to clothes and flesh I believe they are relatively similar.

 

[madmag]

Another question you have to ask is, do the test corelate to real life? If somebody is shooting in to water they usually get the absolute maximum expansion.

Yes, that was my thinking. Not sure how about real life VS the water test.

However, when it comes to clothes and flesh I believe they are relatively similar.

Makes sense...thanks.

 

[Rampant_Colt]

If a bullet does not expand in water, it will likely not expand in living tissue

 

[madmag]

If a bullet does not expand in water, it will likely not expand in living tissue

I agree, but does the water put stress on the round that the human body does not? Rounds appear to do better for fragmentation in gelatin than water.

 

[Rampant_Colt]

The human body is anywhere from 55% to 78% water depending on body size. Don't forget to add skin, muscle and bone into the equation. Bullets expand using simple hydraulics, and water represents the ideal test media. Again, if a bullet won't expand in water, it certainly won't expand in flesh unless bone is encountered

 

[MikeNice81]

Water isn't the ideal medium because it shows a "best case scenario" for each shot. ballistics gel is a better test because it is more analogous to muscle and soft tissue.

Gel gives you a much better of idea what will happen after the bullet penetrates the skin. It doesn't simulate flesh or bone, it simulates muscle and tissue. However it is the closest thing we have. Well the closest you can get without shooting a dead (or living) pig.

 

[madmag]

ballistics gel is a better test because it is more analogous to muscle and soft tissue.

OK, that gets back to one of my original concerns. It appears from my reading that bullets do not fragment as much in gel as water. I don't have collective data, just my take on see and reading tests. If thats the case, then some of the dramatic fragmentation in water may not be a real world result.

Or, maybe I am just looking for an excuse to use some of my older non-bonded ammo.