earlthegoat2
Member
If you do your part they will all put lethal holes in said target.
The issue is in mixing FBI ammunition penetration ratings with standard penetration figures.If one does not care about barrier penetration like the FBI does, that's fine, but the suggestion of 12"-18" of penetration (12" is a minimum standard, and anything up to 18" is progressively better) into simulated bad guy still applies.
Well, actually they're saying that they want 12 to 18" of penetration as defined by their testing.In other words, the FBI is NOT saying that they prefer to have 18" of penetration into bare gelatin so that they can therefore have 12" of penetration after going through barriers. They're saying that they're going to shoot a bunch of test bullets through a variety of barriers, and that they still prefer to have 18" in all cases after the bullet passes through (usually they won't get it, but the closer the better).
The issue is in mixing FBI ammunition penetration ratings with standard penetration figures.
In other words, the fact that the FBI says a particular loading has penetration rating under 12" is not indication that it won't penetrate 12" in a typical self-defense encounter. Their penetration rating is much more stringent than most people understand.Well, actually they're saying that they want 12 to 18" of penetration as defined by their testing.
If you have documentation or support that the FBI prefers 18" in all cases or that anything greater than 12" is progressively better up to 18" I wouldn't mind seeing that.
It is essential to bear in mind that the single most critical factor remains penetration. While penetration up to 18 inches is preferable, a handgun bullet MUST reliably penetrate 12 inches of soft body tissue at a minimum, regardless of whether it expands or not. If the bullet does not reliably penetrate to these depths, it is not an effective bullet for law enforcement use.
It doesn't say anything about their testing protocols because they are readily available and widely known. Here we have an FBI Special Agent from the FBI Firearms Training Unit writing a document for use by the FBI. He is writing about penetration performance standards and using the identical quoted standard (12"-18") described as the performance standard in the FBI ammunition testing protocol. But we're supposed to believe he's not talking about FBI penetration standards and protocols? That seems quite a stretch. What rationale are you providing as the basis for such a leap of faith?It's all about what the bullet does and should do to the bad guy, according to their findings, and says nothing about testing protocols. This is where they recommend a range of penetration depths for ammunition to be sufficiently effective (12"-18"), and that's all I talked about, too: how far a bullet needs to go into the bad guy to be as effective as it can be.
Since it's stated as the lower limit of a range, it's hard to understand how anyone could consider it as ideal. It's clearly "acceptable" but there's nothing implying it's ideal.Many people seem to believe that 12" is what they're suggesting as an ideal depth of penetration...
18" is the maximum acceptable penetration rating.because 18" is supposed to be even better.
It doesn't say anything about their testing protocols because they are readily available and widely known. Here we have an FBI Special Agent from the FBI Firearms Training Unit writing a document for use by the FBI. He is writing about penetration performance standards and using the identical quoted standard (12"-18") described as the performance standard in the FBI ammunition testing protocol.
But we're supposed to believe he's not talking about FBI penetration standards and protocols? That seems quite a stretch. What rationale are you providing as the basis for such a leap of faith?
Since it's stated as the lower limit of a range, it's hard to understand how anyone could consider it as ideal. It's clearly "acceptable" but there's nothing implying it's ideal.
18" is the maximum acceptable penetration rating.
The quote says "penetration UP TO 18". In other words, just as 12" is the lower limit of acceptable (and as you say not ideal), 18" is the upper limit of acceptable. I don't see anything in the document that says it gets better and better as it gets deeper, it just provides two limits and says it needs to stay between them.
If one were to speculate (which I'm not advocating) a far more reasonable interpretation would be that the ideal penetration figure is somewhere in the middle of the two acceptable extremes rather than at one of the extremes.
The point is that an FBI penetration rating is NOT a simple penetration measurement. It is an average of the results from 8 different tests, most of which involve intermediate barriers and those results are the average of five shots.I guess I have absolutely no idea what point you're trying to make.
The point is that if you don't carefully specify the intermediate barriers, etc. then "penetration depth" can mean anything. I could tell you that the penetration depth of round X is consistently zero and unless you know that I measured that penetration depth in a gelatin block on the other side of a 6" concrete block you would have a VERY skewed idea of the penetration capability of round X.Penetration depth is how far a bullet goes into ballistic gelatin after passing through different types of barriers, each measured separately, including no barrier at all, yes or no?
No, he said that: "UP TO 18 inches is preferable". This is clearly stating an upper limit. Otherwise he would have simply said (as you did) that "18 inches is preferable".No, the special agent who wrote the document said that 18" is "preferable."
That's not what it says. I'm reading it directly from the quote in your post and I clicked through to the link and read the document (again) to verify that the quote in your post is correct. It clearly says that "UP TO 18 is preferable". You can't just go through a paper deleting the author's words to support your point of view. That approach is just as invalid as inserting words. The document doesn't say that it's progressively better up to 18".No, they just say that 18" is preferable.
The point is that an FBI penetration rating is NOT a simple penetration measurement. It is an average of the results from 8 different tests, most of which involve intermediate barriers and those results are the average of five shots.
Trying to equate an FBI penetration rating (described above) with a simple penetration depth measurement is misleading.The point is that if you don't carefully specify the intermediate barriers, etc. then "penetration depth" can mean anything.
I could tell you that the penetration depth of round X is consistently zero and unless you know that I measured that penetration depth in a gelatin block on the other side of a 6" concrete block you would have a VERY skewed idea of the penetration capability of round X.
Similarly when the FBI says "12" to 18" of penetration" it's important to know what they mean. It's not the same thing that the man on the street means when he says "12" to 18" of penetration" unless he understands the FBI ammunition testing protocol.
As you know, interposing barriers can drastically alter the penetration of the round and different barriers have different effects.
So when the man on the street says: "I saw a gel block test where round X penetrated 14" and therefore it passes the FBI standards.", that is not a true statement. The round in question might miserably fail to pass the FBI testing protocols due to the effects of intermediate barriers on the round's penetration.
Similarly when an FBI agent talks about round X reliably penetrating to Z inches he's talking about Z inches of penetration with round X as defined by the results of the FBI's testing protocol.
Bottom line, trying to define the performance of a caliber or round using FBI penetration standards without also keeping in mind the FBI penetration testing protocols can give a very skewed idea of what those rounds and calibers will do.
It's not a huge deal, it's just something to keep in mind.
No, he said that: "UP TO 18 inches is preferable". This is clearly stating an upper limit. Otherwise he would have simply said (as you did) that "18 inches is preferable".
The acceptable range is 12" to 18". Acceptable is inside the range, unacceptable is outside the range. 12" is the lower limit, 18" is the upper limit. Rounds must reliably penetrate 12". Rounds must not penetrate more than 18".That's not what it says.
I'm reading it directly from the quote in your post and I clicked through to the link and read the document (again) to verify that the quote in your post is correct. It clearly says that "UP TO 18 is preferable". You can't just go through a paper deleting the author's words to support your point of view. That approach is just as invalid as inserting words. The document doesn't say that it's progressively better up to 18".
For what it's worth, I believe that Fackler goes along with the FBI standard but also states that 12.5" to 14" is ideal which is consistent with the idea that the FBI's standards provide only upper and lower limits on penetration but not IDEAL penetration figures.
damn... some stupid posts in this thread.
unreal. I thought people who invested time into joining online gun forums would do some research and forget some of the gun sales BS they got at the counter when buying their first gun.
Ok, we're talking past each other a bit due to the way the thread topic has drifted over time.Rating? It's not a rating of the performance of any particular load,
OK, here is an example where it's important to understand how a penetration rating is derived. It's an average of results. Therefore one can have a round that goes too deep in one test and still have an average that's acceptable.If it were an upper limit as you claim, then the FBI's main duty load would have failed their own tests, with 19" of penetration through "Heavy Cloth" and 21.8" through "Denim (4 Layers)." I guess it's not an upper limit after all.
I realize that--I even stated in my last post that I was quoting from one of your posts when I put in the "up to". It was only when you were "interpreting" the quote that you left out words that didn't fit your interpretation.Oh, and I did NOT delete the "up to" when I quoted the entire paragraph earlier...
I'm not trying to suppress anything. I've read that paper through several times--quoted it numerous times and linked to it frequently. That's why your interpretation caught my eye as being inconsistent with the actual statement in the document.Knowing this, one can read everything they say and choose to agree or disagree with them, but I want it to be known.
ok, place 9mm and a 45acp on a table with one round in each. someone is coming through the door. which weapon do you pick up to stop the intruder?
there you go
Ok, we're talking past each other a bit due to the way the thread topic has drifted over time.
This thread started off with a question about various calibers and how they perform relative to each other. When you mentioned the FBI penetration standards I merely pointed out that if you're going to talk about relative caliber performance and the FBI penetration standards then it's important to understand their testing protocols.
Then the thread stopped being about comparing calibers and started being primarily about what it takes for a handgun round to be effective regardless of caliber. Once the discussion stopped being about comparing calibers then the testing protocol doesn't enter into it.
OK, here is an example where it's important to understand how a penetration rating is derived. It's an average of results. Therefore one can have a round that goes too deep in one test and still have an average that's acceptable.
I realize that--I even stated in my last post that I was quoting from one of your posts when I put in the "up to". It was only when you were "interpreting" the quote that you left out words that didn't fit your interpretation.
I'm not trying to suppress anything. I've read that paper through several times--quoted it numerous times and linked to it frequently. That's why your interpretation caught my eye as being inconsistent with the actual statement in the document.
ok, place 9mm and a 45acp on a table with one round in each. someone is coming through the door. which weapon do you pick up to stop the intruder?
Shooting through ANYTHING to hit the bad guy is on the outside fringe of possibilities. And if I were doing it, I wouldn't prefer a handgun at all. If I were shooting through a door with my .45, I wouldn't be thinking; "I really wish that I had a 9mm to do this."; I would be thinking; "I really wish I had my AR to do this."
.50BMG isn't guaranteed to knock a man down.