Thoughts on Multiple Assailants, Hit Rate & Capacity

[Hangingrock]

Assumptions are points of convenience in establishing a viewpoint. The true meaning of assume can or may mean: ass-u-me. Other terms “In Theory” or “In All Probability” those are used also in presenting a viewpoint. Data may be manipulated to prove or disprove a position/viewpoint.

In the July issue of Precession Shooting an article Writers Discussion Part II. There is a story related that occurred in South Africa. A South African veteran of Angola interrupted a bank robbery by individuals armed with automatic and semiautomatic weapons. The veteran armed with a BHP (Browning High Power) pistol engaged the individuals at an extended distance, moving, using cover and caused great mischief. The robbers could not locate their antagonist because they looked close but not far or other wise they would have killed him. Now the South African veteran may or may not have had a “Death Wish” but his example would be outside of the accepted norm.

Statistics and grim reality some times clash when your circumstance falls outside the accepted norm. An instructor at the Jungle Warfare School at Fort Sherman in the Canal Zone four decades plus past made the statement “How far up a goat’s rear end can you look” or of recent reference a Special Forces NCO “You don’t know what you don’t know”.

 

[Averageman]

I would like to see how someone with training and practise would do.
I have a fairly extensive amount of training and experiance and shoot between 100 and 300 rounds weekly and participate in IDPA matches on weekends.
I would like to think I have a bit more experiance than the average "Bad Guy" but who knows?

 

[Kleanbore]

Posted by Hangingrock: Assumptions are points of convenience in establishing a viewpoint.

I won't try to speak for John in stating his intent in going through the considerable effort in developing the calculations and displaying them in an understandable manner.

However, for me at least, the assumptions he has chosen do not lend themselves at all toward the establishment of any kind of viewpoint; nor are the assumptions the real key to the message.

What we learn from John's post, and it came as a surprise to me, is a set of probabilities that would apply, given certain reasonably plausible assumptions.

Let's recap the assumptions:

1. Two hits on each assailant constitutes success.
2. The shooter is able to continue shooting until success is achieved or he or she runs out of ammunition.
3. The probability of hitting, which one can vary, is the same for each shot.
4. The shooter stops shooting at the target after having achieved two hits on the target.

How valid are they?

The first one is plausible for the first attacker. Variations from the assumption are likely to be on the high side, reducing the probability of success for a given number of total rounds fired, because one can only go lower by one, but one can go quite a bit higher. For a second attacker, the number could range from zero, should the attacker disengage, to several shots.

If the second assumption proves invalid, success is not achieved--same as not having enough ammunition, or not being able to hit the target.

The third is not realistic, but without it, the stats would be too difficult to present or to comprehend.

Variation from the fourth, which was also necessary to keep the problem reasonably simple, would have to be on the upside and could again reduce the chance of success for the same number of rounds.

Now let's consider the calculations. What they show is that, given those assumptions, having a low capacity firearm in hand may serve well as a deterrent, but should deterrence fail, there is a reasonably high likelihood that the weapon would prove inadequate for the task should the firearm ever be needed.

That, for me, is a real eyeopener.

 

[epijunkie67]

This is exactly why I switched my ccw to a higher capacity weapon. Although I never had such concrete numbers I've done a lot of reading about civilian firearms engagements. In a surprisingly large number of cases the weapon was fired until empty. In a surprisingly large number of cases more than one assailant was involved. Reloading is also unlikely to occur.

I came away with the sense that in a real world firefight 6 rounds was very likely to be insufficient. Obviously we can't carry around ARs and AKs with 30 round mags but we can carry a larger capacity handgun. I recently purchased an M&P9c and a PT111 that both double the round count of my PM9. After breaking them both in and determining their reliability I'll be switching to one as my ccw.

 

[Lawdawg45]

I would like to see how someone with training and practise would do.
I have a fairly extensive amount of training and experiance and shoot between 100 and 300 rounds weekly and participate in IDPA matches on weekends.
I would like to think I have a bit more experiance than the average "Bad Guy" but who knows?

Good comment, and the type of training is critical. For decades LEO's have put millions of rounds down range but still had a 50% drop in accuracy under real fire, and research showed the Parasympathetic Nervous System (fight or flight syndrome) to be the biggest opponent. Training for recruits recently has been modified to simulate this reaction by adding physical endurance sprints immediately before firing, such as running full tilt for a 100 yards or crawling through an obstacle course, and some even use flash bang devices.

LD

 

[PabloJ]

Good comment, and the type of training is critical. For decades LEO's have put millions of rounds down range but still had a 50% drop in accuracy under real fire, and research showed the Parasympathetic Nervous System (fight or flight syndrome) to be the biggest opponent. Training for recruits recently has been modified to simulate this reaction by adding physical endurance sprints immediately before firing, such as running full tilt for a 100 yards or crawling through an obstacle course, and some even use flash bang devices.

LD

These results are not surprising at all. When I see husband or boyfriend help gal or significant other but five shot revolver I cringe....."the tear gas/stun gun section is over there folks". I suspect a person with tinge of sociopathy would outscore most even members of elite fighting units.

 

[Owen Sparks]

In the real world if you start shooting people usually scatter like chickens unless you are facing a professional military unit. Self sacrifice in combat requires highly diciplined people who are willing to put the mission above their own lives. Common criminals usually are selfish and lazy by nature and want something for little effort. That is why they would rather steal than work. People like this are usually not going to lay down their lives so that one of their buddies can walk off with your giant screen plasma TV. If you shoot the first one there probably will not be any more targets.

 

[Hangingrock]

From the perspective of a youthful inexperience of bringing a pistol to a rifle fight armed with a 1911A1 and three (seven round) magazines. One of my three MOS’s dictated that I’m issued the previously mentioned pistol as opposed to a rifle. So that said I am not primarily a shooter. The problem is that circumstances/situations are lest we say not as we would envision or like them to be.

So when some one runs a spread sheet in regards to potential wounding/lethal hits and weapon ammunition capacity rationalizing a certain number of wounding/lethal hits solves a problem or has the potential to solve a problem I’m a skeptic based on my experiences which are I’ll say limited but lasting impressions.

Two solid hits to what is referred to as center mass with a 1911A1, one with a M1 carbine, and the finishing shot with a M14 the recipient being knocked down twice before finally being put out of the fight. There were more shooting incidents that day but the first typifies the fact by the end of the day I had supplemented my pistol with a rifle.

In closing one may also be a recipient of wounding/lethal hits.

 

[Kleanbore]

Posted by Owen Sparks: If you shoot the first one there probably will not be any more targets.

That is of course a possibility, but one has to decide in advance whether to accept or to mitigate the very real risk that it will not turn out that way.

In any event, that point was already addressed in Post #13:

That [(the assymption that in 99.9% of such cases a single gunshot ... will scatter the attackers)] 's another thing that cannot be predicted.

In an incident in which a couple of robbers try to take something for the sake of its monetary value, a second perp will likely run after the shooting starts, if he can safely do so, to rob again some other day.

If he cannot, all bets are off.

If quickly obtaining a car different from the one they have been driving, or a car with a higher supply of gasoline, or a car that is still able to be driven, is essential to the continued travel and to the escape of the perps(perps of that kind are very common along the highways that go through our area), it would seem very imprudent to count on anyone taking off after the shooting starts.

It was also addressed in Post # 28.

For a second attacker, the number [of shots] could range from zero, should the attacker disengage, to several shots.

Let's ty to avoid going in circles here.

 

[Owen Sparks]

Therefore, we can assume that unless you are involved in international espionage, are a major player in the illicit drug trade or you are a Don of a major Mafia family your chances of being assaulted in your home by a paramilitary death squad are essentially zero. Take cover and start shooting and the bad guys will scramble. Someone once did a study of over 20 years worth of 'The armed citizen' articles from the American Rifleman and there was not one case of a besieged homeowner having to reload while fighting off intruders.

 

[JohnKSa]

So when some one runs a spread sheet in regards to potential wounding/lethal hits and weapon ammunition capacity rationalizing a certain number of wounding/lethal hits solves a problem or has the potential to solve a problem I’m a skeptic based on my experiences which are I’ll say limited but lasting impressions.

There is nothing in the calculations or the assumptions relating to wounding or lethality.

The idea was to find out what the likelihood of scoring 2 or more hits on either one or two attackers (depending on the numbers poked into the spreadsheet) given a fixed hit rate probability (another number poked in) and a certain number of shots (a third parameter than can be varied) available to accomplish that goal.

The calculations do that and nothing more.

Two solid hits to what is referred to as center mass with a 1911A1, one with a M1 carbine, and the finishing shot with a M14 the recipient being knocked down twice before finally being put out of the fight. There were more shooting incidents that day but the first typifies the fact by the end of the day I had supplemented my pistol with a rifle.

Yup, tried to make that point. The results assume that 2 hits is enough. That means that your experience shows that the probability of success may actually be WORSE than what was calculated for a given capacity/# of shots and hit rate.

In closing one may also be a recipient of wounding/lethal hits.

Tried to make that point as well. The assumption is that the defender will get to fire all his rounds. Obviously that isn't always true in the real world, nor is it generally true that your hit rate probability will remain the same after being hit yourself.

The calculations give a sort of "best case" answer based on the stated assumptions. It's certainly possible, that neutralizing a person in the real world might take more than 2 hits from a carry pistol or that a person might be killed or badly injured before firing all his shots.

There's no way to factor all that in, and there's no attempt made to do so. The results provide a limited insight into one very narrowly defined aspect of handgun self-defense. They are not intended to, nor has any claim been made that they fully and accurately replicate all the intricacies of a real-world gunfight.

Therefore, we can assume that unless you are involved in international espionage, are a major player in the illicit drug trade or you are a Don of a major Mafia family your chances of being assaulted in your home by a paramilitary death squad are essentially zero. Take cover and start shooting and the bad guys will scramble. Someone once did a study of over 20 years worth of 'The armed citizen' articles from the American Rifleman and there was not one case of a besieged homeowner having to reload while fighting off intruders.

The bad guys will scramble except when they don't. It's true that bad guys tend to run when the shooting starts, but it's also true that's only a tendency, not an absolute.

1. If you're convinced that the bad guys will always scramble when you "take cover and start shooting" you can dispense with a firearm entirely and just carry a noisemaker that looks convincingly like a gun.

2. If you don't believe there's any chance at all of facing multiple attackers then take a look at the first part of the OP that deals with facing a single attacker and ignore the rest.

 

[Owen Sparks]

Very few people are willing to 'take one for the team' outside of the military. If you respond with armed resistance most criminals will flee unless cornered. Real life is not like an IDPA match where the bad guys are stapled to targer frames and can not run away.

 

[Kleanbore]

Posted by Owen Sparks: Therefore, we can assume that unless you are involved in international espionage, are a major player in the illicit drug trade or you are a Don of a major Mafia family your chances of being assaulted in your home by a paramilitary death squad are essentially zero.

What that has to do with this discussion, I don't know.

Someone once did a study of over 20 years worth of 'The armed citizen' articles from the American Rifleman and there was not one case of a besieged homeowner having to reload while fighting off intruders.

Reloading is not the subject of this thread, and the cited study, which has been covered here several times, is completely irrelevant to the discussion.

Very few people are willing to 'take one for the team' outside of the military.

Allrighty, then. The question is, what might a second assailant decide to do for himself.

If you respond with armed resistance most criminals will flee unless cornered.

One more time, do you really think it prudent to base your strategy upon what you think "most criminals" will do?

What is it that you are trying to say?

 

[LiveLife]

Someone once did a study of over 20 years worth of 'The armed citizen' articles from the American Rifleman and there was not one case of a besieged homeowner having to reload while fighting off intruders.

Recent home invasions involving more than one intruder (first example with three robbers pretending to be FBI agents):

http://abclocal.go.com/kabc/story?section=news/local/los_angeles&id=8273717

suspects were wearing ski masks and had badges identifying themselves as FBI agents when they barged into the home after midnight Wednesday.

http://www.fresnobee.com/2012/06/22/2884664/4-guilty-in-valley-home-invasion.html

The four defendants were part of a crew of 10 suspects who targeted affluent homeowners in Fresno and Merced counties

http://abclocal.go.com/kabc/story?section=news/local/los_angeles&id=8535612

several men entered the house at around 3 a.m. on Wednesday.

A couple in their 60s was sleeping when the suspects rang their doorbell and kicked open their front door. The men barged into their bedroom

http://www.utsandiego.com/news/2012/jun/11/home-invasion-robbery-in-san-marcos/

Three men, one armed with a knife and one armed with a semi-automatic handgun, entered the residence ... They told the man not to call authorities and bound him with zip-ties

http://www.mercurynews.com/californ...sco-victims-held-at-gunpoint-mission-district

Two suspects barged into a home in San Francisco's Mission District and held several people at gunpoint while they ransacked the residence on Wednesday night, police said. The suspects, two men believed to be in their 30s, came through the front door carrying handguns

http://abclocal.go.com/kabc/story?section=news/local/los_angeles&id=8543730

four men accused in two home-invasion robberies ... The first robbery happened on the 1000 block of South Dwight Avenue. The second robbery occurred 45 minutes later on the 400 block of North Kemp Avenue.

http://scoopsandiego.com/news/local...cle_b9d7ce0e-b184-11e1-966a-001a4bcf6878.html

http://abclocal.go.com/kabc/story?section=news/local/los_angeles&id=8475027

http://abclocal.go.com/kabc/story?section=news/local/orange_county&id=8459020

http://abclocal.go.com/kabc/story?section=news/local/orange_county&id=8352431

http://abclocal.go.com/kabc/story?section=news/local/los_angeles&id=8543377

http://abclocal.go.com/kabc/story?section=news/local/los_angeles&id=8582196

http://www.fresnobee.com/2012/06/26/2888616/police-seek-3-in-northwest-fresno.html

 

[Teachu2]

If success (survival) is the goal, it might be wise to consider other options. Drawing and shooting it out isn't going to be a wise course of action unless you're sure they'll give up easily or unless there is no other reasonable course of action available.

Bold underline mine.

Isn't that always the case?

The scenario here - multiple determined attackers - is still pretty rare for people not engaged in high-risk occupations. In my area, home invasions have been limited to targeted individuals who run cash businesses, ie pawnbrokers and drug dealers.

The odds can be shifted favorably three ways: more capacity, better accuracy, and more effective caliber choice. If you move from a .38 snubbie 5-shooter with a 30% hit rate to a .45acp 10+1 with a 50% hit rate, the odds of going home increase significantly.

There are other problems with applying the 30% police rate. Granted, it's a real-world number for that particular group, but (as a former LEO) I believe that I can still outshoot the majority of LEOs - as can many firearms enthusiasts. Practice is key - and a very high % of LEOs simply do not practice. Some members here shoot more rounds in a year than many LEOs do in a career.

Bottom line - carry as much gun as you can shoot well, and practice often. Pay attention to your surroundings, and avoid high-risk behavior. If the SHTF, make your 1st shot count - it may be all you'll need.

 

[JohnKSa]

Isn't that always the case?

At the risk of hijacking my own thread, no, it isn't always the case. Generally speaking, compliance, as a tactic, offers a high probability of surviving uninjured. When faced with two determined armed attackers, it's highly likely that compliance offers a better chance of surviving uninjured than trying to shoot it out.

The odds can be shifted favorably three ways: more capacity, better accuracy, and more effective caliber choice. If you move from a .38 snubbie 5-shooter with a 30% hit rate to a .45acp 10+1 with a 50% hit rate, the odds of going home increase significantly.

The calculations make no attempt to compare calibers, but the results indicate that increasing capacity (with the assumption that the defender is able to make use of that capacity) and increasing the hit rate probability both improve the chances of "success" as defined by scoring 2 or more hits on each attacker.

There are other problems with applying the 30% police rate.

The 30% hit rate assumption applies only to the two tables. The plots provided allow you to determine the chances of "success" for any capacity from 5 rounds to 11 rounds with any hit rate probability from 10% to 90%. There's an explanatory paragraph above each plot that tells how to use them.

 

[Lawdawg45]

Very few people are willing to 'take one for the team' outside of the military. If you respond with armed resistance most criminals will flee unless cornered. Real life is not like an IDPA match where the bad guys are stapled to targer frames and can not run away.

When you or I feel threatened, the weapon comes out. When we fear for our life, we open fire. Why do we assume that a career criminal or group of career criminals would do anything less?

LD

 

[Kleanbore]

Posted by Teachu2: The scenario here - multiple determined attackers - is still pretty rare for people not engaged in high-risk occupations.

In On the Best Defense: Multiple Attackers (Number 50, Episode 11 Season 4) which has been linked in a previous post, Michael Bane states,

A mugging situation is often thought of as a one on one attack. In most cases, there are more than one. This is reality you need to factor in when it comes to your self defense plan.

In that program, it is pointed out that whether it is necessary to employ deadly force against a second attacker is a question--a question that one will likely have to answer very quickly indeed.

In the data set that has been linked in Post #13, multiple attackers were involved in 75% of the incidents.

The question is, for what do you want to prepare?

In my area, home invasions have been limited to targeted individuals who run cash businesses, ie pawnbrokers and drug dealers.

If you say so--but that is irrelevant to the discussion.

Also irrelevant, but worth keeping in mind, is that violent criminal attacks are more prevalent outside the home than inside.

There are other problems with applying the 30% police rate.

I see that John has already responded to that.

The 30% hit rate assumption applies only to the two tables. The plots provided allow you to determine the chances of "success" for any capacity from 5 rounds to 11 rounds with any hit rate probability from 10% to 90%. There's an explanatory paragraph above each plot that tells how to use them.

 

[Billy Shears]

When you or I feel threatened, the weapon comes out. When we fear for our life, we open fire. Why do we assume that a career criminal or group of career criminals would do anything less?

Because you and I are being attacked and defending ourselves; they're not. There's a big difference.

As I've said, human predators are like any other predators, they're looking for prey not a fight. If a target looks like too tough a nut to crack, they often back down and go in search of easier prey. Sure there are exceptions, but this is why lots of would be muggers are driven off without a shot ever being fired when their intended victim produces a gun. This instinct for self preservation doesn't abandon criminals when they operate in groups, nor does their innate selfishness.

 

[jimbo555]

It boils down to whether you have a low capacity or a high capacity firearm if you are confronted by multiple determined and trained individuals you will most likely lose.

 

[Kleanbore]

Posted by Billy Shears: This instinct for self preservation doesn't abandon criminals when they operate in groups, nor does their innate selfishness.

I think we can accept that for the general case, possible exceptions being meth addicts.

So, the operative question would seem to be whether or not the criminal would think that breaking off the attack would be best way to escape and survive.

He may well see it that way. Or not, particularly if...

• He is blocked from escaping.
• You are firing, and he is close enough to cut you, and turning around would put him at greater risk.
• The only safe and effective means of escape available to him at the time involves the taking of your automobile.

Again, the question becomes whether you want to limit your preparations to those required for the general case. I do not.

 

[Skribs]

You have to prepare for what you believe will occur. If you believe that multiple attackers will scatter 99% of the time, and that it isn't prudent to prepare for a situation where they don't (or where you miss), then by all means, prepare to take down one attacker and scatter the others. If they don't scatter, then its a fight you'll lose. Of course, I'm not trying to be argumentative, it's just a very likely outcome in that unlikely situation. With any defense and preparation you have ready, there is something that will defeat it.

With that all said, I come from a background of gaming, and specifically theorycrafting. I'm the guy that does the spreadsheets to figure out exactly how much throughput I can get with various builds in games that I play. So I LOVE this kind of math. Yes, it makes a lot of assumptions, but one has to make a lot of assumptions in order to even compare, as the OP said. Also, based on statistics and generic training, I don't think the OP's assumptions were all that wild.

I agree with one of Kleanbore's earlier posts, I'd fire multiple shots between assessing whether or not the target has stopped. If you fire 4 shots from a J Frame on the first target, you have one shot left for the second target...if you stopped the first target.

I'll admit, when I first started looking at the 9mm over the .40 or .45, it wasn't to get "moar bullets", it was actually to get double-digit round count in a smaller package. Although the more I look at things, the more I wonder how many would be "enough". Like the OP said, if you assume a 30% hit rate and need 4 hits to "win", then 12 rounds would only give you a 50% chance of success.

I did my math a bit differently, simply took the capacity times the accuracy, and I still get 3.6 hits out of 12 rounds, with 30% accuracy. In order to average 4 hits, you'd need 13.33 rounds (I round up to 14). I think the OP was using a more statistical model, mine is a simpler equation, but it says a lot. In order to average 6 hits (3 attackers) you need to carry an XDm 9 with +1 or a FiveseveN (or use an extended magazine).

Really makes me think twice about a revolver, a pocket pistol (as primary), or carrying without reloads.

 

[mcole]

one can improve the % of center mass and head shots, significantly and consequentially, by learning to "point shoot." one must also learn to also remain calm. mcole

 

[Skribs]

one must also learn to also remain calm

How exactly does one practice remaining calm in a self defense situation, without putting themselves in self defense situations?

 

[Lawdawg45]

Because you and I are being attacked and defending ourselves; they're not. There's a big difference.

As I've said, human predators are like any other predators, they're looking for prey not a fight. If a target looks like too tough a nut to crack, they often back down and go in search of easier prey. Sure there are exceptions, but this is why lots of would be muggers are driven off without a shot ever being fired when their intended victim produces a gun. This instinct for self preservation doesn't abandon criminals when they operate in groups, nor does their innate selfishness.

I agree, and when you step out by yourself with a weapon, that's when the 2 or 3 home invaders will open up on you. You speculate that they will run, but statistics show they often stay and fight.

LD