Bang Flop Research - a year on

NigelM

Well-Known Member
This time last year I put out an appeal for some help with research into the Bang Flop phenomena.

12 months on and 5 of us have contributed to the data pool and we have good information on 141 deer shot in the chest. We are not interested in head or neck shots, we all know what happens to them already.

Because there are so many different calibre's, bullet weights, bullet constructions, terminal velocities, species etc. our data pool is still not large enough to come up with too much in the way of conclusions. We set out to get 1000 records and it looks like we will have to get that many to prove anything.

I was very fortunate that one of the SD members volunteered to help work on the data. He is a scientist, statistician and keen stalker. His analysis of the data has been very professional and he has kept me on the straight and narrow. I will not mention his name here, but he will make himself known if he wants to.

There are some patterns emerging, but the numbers we have for each calibre and bullet type are not great enough to prove anything statistically.

A couple of things we have been able to prove statistically.

The greater the awareness of the deer to imminent danger the lower the chance of a Bang Flop.

Awareness on colapse.png
The larger the animal the lower the chance of a Bang Flop.

Weight on colapse.png

The faster you drive a bullet the higher the chance of a Bang Flop.

MV on BF.png

What we want to get into is the effect that calibre has, the effect that bullet weight has and the effect that bullet construction has. To get there and prove it beyond reasonable doubt we are going to need help.

This is an appeal to all you guys to help by sending us your data. I have a simple spreadsheet that we would ask you to complete with each deer shot. When you get to 10 on the sheet just send it back to me and we will add yours to the pool of data. Your chance to be part of a study that could give us all some proven answers on subjects that we all spend a lot of time discussing.

We are interested in everyones data. Everything is relevant - providing it's UK deer species shot with a legal calibre. There are so many gaps it's difficult to go through all of them, but here are a few we would like to get hold of:

Those driving .30 cal bullets over 3000 fps MV
Anyone with a 270
Anyone driving 7mm bullets slowly
.25 cal
Anyone using Barnes TTSX or TSX bullets

Remember, it's chest shots only.

If you can help please PM your email address to me and I will send out the form and instructions.

Thanks,

NigelM
 
Nigel, I was also thinking of the following. Were the bullets pass throughs or not. What was the size of the deformed bullet if it was not a pass through?
 
So I keep detailed records for all deer shot by Myself or guests going back years with my own rifles.
The rifles used during the last 5 years on all the UK deer are, 243, 7x57, 7x64, 308, 375 and I even have data for .729[12 bore]from 20 years ago.
Would any of this be useful.?
 
So I keep detailed records for all deer shot by Myself or guests going back years with my own rifles.
The rifles used during the last 5 years on all the UK deer are, 243, 7x57, 7x64, 308, 375 and I even have data for .729[12 bore]from 20 years ago.
Would any of this be useful.?

That would ALL be extremely useful!
 
This is a fantastic start to a vey worthwhile project. Having seen the results so far I would ask that anyone who can help, even with a few cases steps forwards and joins in. The data collection is not difficult or arduous but the results have the potential to change how we conduct our stalking activities. Surely we must be able to get to 1000 cases between us all!
 
Just to say that I'm the one responsible for the statistics.

The figures that Nigel has posted have robust statistical support, and are not terribly controversial (which means that I have confidence in our ability to detect genuine patterns).

However, we do need a lot more data, especially in the areas Nigel has outlined.
 
Nigel, I was also thinking of the following. Were the bullets pass throughs or not. What was the size of the deformed bullet if it was not a pass through?

In terms of the outcome we're interested in, this shouldn't matter: we have data on bullet weight, bullet construction, velocity, animal live weight and shot distance. Those variables will be the ones that largely determine whether or not you get a pass through.

Think of it this way: whether or not you get a pass through is really an OUTCOME rather than a contributing variable.
 
So I keep detailed records for all deer shot by Myself or guests going back years with my own rifles.
The rifles used during the last 5 years on all the UK deer are, 243, 7x57, 7x64, 308, 375 and I even have data for .729[12 bore]from 20 years ago.
Would any of this be useful.?

That would be fantastic. PM me your email address and I will send you the forms out.

Thank you.
 
This is a fantastic start to a vey worthwhile project. Having seen the results so far I would ask that anyone who can help, even with a few cases steps forwards and joins in. The data collection is not difficult or arduous but the results have the potential to change how we conduct our stalking activities. Surely we must be able to get to 1000 cases between us all!


Just to echo this: it doesn't matter how few records you have - any will do. Especially people shooting slower cartridges (7X57, 6.5X55, 7X65R), people shooting fast 30cals (300WM, hot loads for .30-06), people shooting 6mms at larger species, and people shooting copper bullets at any speed.
 
Kevin "Doctari" Robertson a qualified Zimbabwe vet has extensively written about this subject in his book "The Perfect Shot" and also goes onto demonstrate in his accompanying DVD the cause of the apparent randomness of chest shots that result in either runners or dead on the spot kills.

He also advocates heavy for calibre bullets at moderate speeds which he believe dumps more energy into the animal, he must know something as Norma do an entire range of bullets based on his findings.
 
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In terms of the outcome we're interested in, this shouldn't matter: we have data on bullet weight, bullet construction, velocity, animal live weight and shot distance. Those variables will be the ones that largely determine whether or not you get a pass through.

Think of it this way: whether or not you get a pass through is really an OUTCOME rather than a contributing variable.

I have to think about this. Yes its an outcome but it may tell me more about what is the mechanism by which the animal dies or is incapacitated instantly. On the larger animals, I am now completely focused on penetration. If a large deer is shot at say 300 yards, if the bullet has completely penetrated the chest cavity it generally has taken out both lungs, the deer may or may not run. If the bullet doesn't penetrate the animal may still survive even with one lung and might almost definitely run.


From the last study on moose than Nigel posted I was interested in the distance of the animal travelled after the shot with 0 being bang flop obviously. I would like to see the statistics around the distance travelled, ie up to 500m.

Another thing I have found is the quantity of the blood trail. On average I'm only finding a good blood trail very 10th deer. Many times I get hardly a drop even though the bullet has completely penetrated both sides. I guess I'm asking for some scope creep but if the animals doesn't go down immediately, statistically I'd like to know what is combination providing the lowest possible travel distance and/or the best blood trail to follow up on.
 
Well done for initiating some meaningful research, with hopefully plenty more to come. I've sent Nigel a PM in order to sign up for data collection.

Can I ask though, does 'chest shot' mean anywhere forward of the diaphragm? Basically, are we counting high shoulder shot deer in the same category as ones shot in the heart/lungs? As the high shoulder shot will surely have a higher incidence of bang flops.
 
Josh, there are three shot placement options, Heart, Lung and Shoulder. The shoulder category will cover your high shoulder shots.
 
Well done for initiating some meaningful research, with hopefully plenty more to come. I've sent Nigel a PM in order to sign up for data collection.

Can I ask though, does 'chest shot' mean anywhere forward of the diaphragm? Basically, are we counting high shoulder shot deer in the same category as ones shot in the heart/lungs? As the high shoulder shot will surely have a higher incidence of bang flops.

We're counting anything in front of the diaphragm that doesn't hit the spine.

We then ask for more info on exact placement (heart, lung, shoulder) to deal with the fact that shoulder shots may cause a higher probability of instant collapse.

So far, based on the data we have, there is no statistically detectable effect of placement - but we have a relatively small sample of shoulder shots.
 
I have to think about this. Yes its an outcome but it may tell me more about what is the mechanism by which the animal dies or is incapacitated instantly. On the larger animals, I am now completely focused on penetration.
If a large deer is shot at say 300 yards, if the bullet has completely penetrated the chest cavity it generally has taken out both lungs, the deer may or may not run.
If the bullet doesn't penetrate the animal may still survive even with one lung and might almost definitely run.

not sure that is the case in the UK
It might be on very heavy skinned or heavy boned animals

I would say a very high %age of the single side penetrations have resulted in bullets recovered under the skin or in the ribs of the opposite side.
Those that went off on an angle and didn't exit was not down to bullet failure to penetrate but angle of shot


Another thing I have found is the quantity of the blood trail. On average I'm only finding a good blood trail very 10th deer. Many times I get hardly a drop even though the bullet has completely penetrated both sides. I guess I'm asking for some scope creep but if the animals doesn't go down immediately, statistically I'd like to know what is combination providing the lowest possible travel distance and/or the best blood trail to follow up on.


lack of blood through entry/exit would indicate mostly lung and no major destruction of blood vessels.
A High lung could drop them quickly due to shock to the spine
A Low lung/Heart with vessel or heart destruction usually sees blood exit the wound hole under pressure as the animal moves off

the only time I have seen a combination of both on clear display was when I shot a large red stag a while back and found the bullet under the skin on the opposite side but the chest cavity looked like a raspberry smoothie.

The blood flow from entry and nose/mouth was incredible.
it fell 5-10 yards from where it was standing after a brief stagger and basically bleed out through the nose and mouth leaving a pool of blood about 18" in diameter in heather/moss.
 
So in partial answer to the questions about distance run, here are the results FROM THIS DATA SET AS IT CURRENTLY STANDS:

View attachment 67261




I look forward to the howls of anguish from the 6.5 fans... the data are what they are, folks. If you think it's unrepresentative, send in your own.
 
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not sure that is the case in the UK

lack of blood through entry/exit would indicate mostly lung and no major destruction of blood vessels.

Maybe but I've seen 7mm holes, 30 cal holes, 338 cal holes , 35 whelen holes, 9.3x62 holes, 375H&H holes and 45/70 holes. The larger the hole the less likely the skin can closer over the wound. I've notice that it doesn't take much for the combination of mud/hair/blood to clot very quickly. The larger the hole the less like this will happen and by the time you get to the 9.3 nothing is going to close over, this is especially if you are not getting complete pass throughs with bullets that haven't deformed.
 
not sure that is the case in the UK
It might be on very heavy skinned or heavy boned animals

I would say a very high %age of the single side penetrations have resulted in bullets recovered under the skin or in the ribs of the opposite side.
Those that went off on an angle and didn't exit was not down to bullet failure to penetrate but angle of shot.

Nigel's survey includes impact velocity. For example I would find it very difficult to believe that a 243Win using 80gr sp would penetrate to the other side of a red stag at 300m, however if somebody provides statistically to the contrary I'll believe it.
 
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