Im trying to get some more information on danger space for long range hunting. Danger space is the amount your range estimation can be off and the flatter a round shoots is the more danger space you have? Thanks
Range Report Danger Space Info Needed
- Thread starter bjax919
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Re: Danger Space Info Needed
Buy "Applied Ballistics for Long Range Shooting" by Bryan Litz. He is Berger bullets chief ballistician and the book has most of the information you will ever need when it comes to calculating ballistics equations.
Josh
Buy "Applied Ballistics for Long Range Shooting" by Bryan Litz. He is Berger bullets chief ballistician and the book has most of the information you will ever need when it comes to calculating ballistics equations.
Josh
Re: Danger Space Info Needed
Danger space is the distance beyond the backstop where an errant round could cause harm. I believe you are looking for the "maximum point blank range" term. I second the recommendation for Litz's book.
Danger space is the distance beyond the backstop where an errant round could cause harm. I believe you are looking for the "maximum point blank range" term. I second the recommendation for Litz's book.
Re: Danger Space Info Needed
I actually am waiting for it to arrive in the mail. Is there a formula for danger space in the book? Definetely not looking for MPBR. I'm trying to decide what bullet is best for my .308 Win. for long range hunting,deer at 600yds, currently using 208gr AMax and have the largest danger space.
I actually am waiting for it to arrive in the mail. Is there a formula for danger space in the book? Definetely not looking for MPBR. I'm trying to decide what bullet is best for my .308 Win. for long range hunting,deer at 600yds, currently using 208gr AMax and have the largest danger space.
Re: Danger Space Info Needed
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bjax919</div><div class="ubbcode-body">Im trying to get some more information on danger space for long range hunting. <span style="font-weight: bold">Danger space is the amount your range estimation can be off and the flatter a round shoots is the more danger space you have?</span> Thanks </div></div>
Correct. This is "danger space" in the context of tactical shooting.
Flatter rounds have a little more hit probability given a certain range estimation error.
Of course it also depends on the vertical size of your target (or killing zone within the target).
"Point blank range", for a certaing trajectory and certain zero, is the same concept but applied only from muzzle to X range for a certain Y target size. More used for hunting.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bjax919</div><div class="ubbcode-body">Im trying to get some more information on danger space for long range hunting. <span style="font-weight: bold">Danger space is the amount your range estimation can be off and the flatter a round shoots is the more danger space you have?</span> Thanks </div></div>
Correct. This is "danger space" in the context of tactical shooting.
Flatter rounds have a little more hit probability given a certain range estimation error.
Of course it also depends on the vertical size of your target (or killing zone within the target).
"Point blank range", for a certaing trajectory and certain zero, is the same concept but applied only from muzzle to X range for a certain Y target size. More used for hunting.
Re: Danger Space Info Needed
MPBR falls far short of maximum danger space, and is a hunter's term based on vertical deviation from line of sight.
Maximum danger space, for me, is based on residual terminal energy; mainly how far away can the bullet still manage to deliver dangerous terminal energy; and is most likely well beyond the point where it goes subsonic. For my purposes, I'd suggest a minimum of twice the transonic distance.
Greg
MPBR falls far short of maximum danger space, and is a hunter's term based on vertical deviation from line of sight.
Maximum danger space, for me, is based on residual terminal energy; mainly how far away can the bullet still manage to deliver dangerous terminal energy; and is most likely well beyond the point where it goes subsonic. For my purposes, I'd suggest a minimum of twice the transonic distance.
Greg
Re: Danger Space Info Needed
It appears what your asking for and what your looking for is two different things.
Danger space is where the bullet will still hit something "on" the target beyond or in front of the estimated POI range. With a 208 at 600 yards, using generic calculations @ 2500fps, you have about 10 yards (+/- 5 yards) of "miss guess" where the boolet will still strike a 6" vital area (3" high - 3" low).
From 550 to 640 the boolet will still be able to hit some part of the critter assuming a 40" critter height. That's hoof to ears.
For hunting men danger space is handy, for hunting stuff you want to eat ----- not so much.
On a ballistics table use the BULLET PATH in inches to determine what you are looking for. If you don't know the exact velocity and characteristics of your boolet/cartridge/rifle combo stay inside 300 yards. That's just my hunting ethics though.
Cheers,
Doc
It appears what your asking for and what your looking for is two different things.
Danger space is where the bullet will still hit something "on" the target beyond or in front of the estimated POI range. With a 208 at 600 yards, using generic calculations @ 2500fps, you have about 10 yards (+/- 5 yards) of "miss guess" where the boolet will still strike a 6" vital area (3" high - 3" low).
From 550 to 640 the boolet will still be able to hit some part of the critter assuming a 40" critter height. That's hoof to ears.
For hunting men danger space is handy, for hunting stuff you want to eat ----- not so much.
On a ballistics table use the BULLET PATH in inches to determine what you are looking for. If you don't know the exact velocity and characteristics of your boolet/cartridge/rifle combo stay inside 300 yards. That's just my hunting ethics though.
Cheers,
Doc
Re: Danger Space Info Needed
The army use to have a manual for setting up ranges listing the "danger space". I don't remember which one, I turned all that stuff over to my replacement when I retired from the NG in '92.
You could contact "Range Central" for any army base and they will give you the information.
The NRA also has information for setting up ranges including info on the "danger zone".
Gen Hatcher (Hatcher's Notebook) has a good method of determining the danger zone or max range small arms will go in a vacuum:
"divide the MV by 10, then squaring that result"
Heavy bullets a lower velocities max range would be 15-20% of that.
However higher BC puts that distance closer to the vacuum range. Hatcher shows the 45 ACP will .93 miles & 12% of max. vacuum range. M2 ball is 1.99 miles and 6% of VR.
M2 (50 Cal) is 4.13 miles and 9% of VR.
Whether the round has the remaining energy to kill or injure is a differant matter, however, you don't need to kill or injure, you just need rounds landing to get your range shut down.
I reciently laid out a pistol range for our local club. The problem was, the pistol range was next to our rifle range. So if shooting 50 yards with a pistol, and you, for example let a round go toward the rifle range, how were we going to protect the rifle shooters who may be down range changing targets. I figured the max. hight of the slowest pistol round, ( I think I used the 38 spl WC target round), to figure how high a seperation berm would have to be to make sure the round would over fly the rifle range. That works for lateral shots, but not down range.
The way that was laid out is to find a hill for a back stop that is higher then the Max ordinate of the rounds being fired. That's easy to do in Wyoming, not so in some of your "flat states".
I think using the guide lines set by the Army and/or NRA will help you in the liability department and might keep your range fron getting shut down.
The army use to have a manual for setting up ranges listing the "danger space". I don't remember which one, I turned all that stuff over to my replacement when I retired from the NG in '92.
You could contact "Range Central" for any army base and they will give you the information.
The NRA also has information for setting up ranges including info on the "danger zone".
Gen Hatcher (Hatcher's Notebook) has a good method of determining the danger zone or max range small arms will go in a vacuum:
"divide the MV by 10, then squaring that result"
Heavy bullets a lower velocities max range would be 15-20% of that.
However higher BC puts that distance closer to the vacuum range. Hatcher shows the 45 ACP will .93 miles & 12% of max. vacuum range. M2 ball is 1.99 miles and 6% of VR.
M2 (50 Cal) is 4.13 miles and 9% of VR.
Whether the round has the remaining energy to kill or injure is a differant matter, however, you don't need to kill or injure, you just need rounds landing to get your range shut down.
I reciently laid out a pistol range for our local club. The problem was, the pistol range was next to our rifle range. So if shooting 50 yards with a pistol, and you, for example let a round go toward the rifle range, how were we going to protect the rifle shooters who may be down range changing targets. I figured the max. hight of the slowest pistol round, ( I think I used the 38 spl WC target round), to figure how high a seperation berm would have to be to make sure the round would over fly the rifle range. That works for lateral shots, but not down range.
The way that was laid out is to find a hill for a back stop that is higher then the Max ordinate of the rounds being fired. That's easy to do in Wyoming, not so in some of your "flat states".
I think using the guide lines set by the Army and/or NRA will help you in the liability department and might keep your range fron getting shut down.
Re: Danger Space Info Needed
OP,
The formula is in there along with many others. Bryan's a smart dude and explains everything very well.
Josh
OP,
The formula is in there along with many others. Bryan's a smart dude and explains everything very well.
Josh
Re: Danger Space Info Needed
What Im doing is using Bryans Max Effective Range to decide the distance for "ethical" hunting shot and have always thought the distance you can almost guarantee POI in a 12in circle then thats acceptable for deer or anything larger. That being said I determine distance for whitetail having 12in vitals or 14-16in for mule deer. I have lots of time behind the scope shooting 600yds and closer and with 10mph wind say 90% of the time I'll hit well into 1.5 MOA, regularly .50 to .75 MOA, and with 20mph within 3 MOA so for a hunting situation any wind over a full value would mean a closer shot. So now using danger space to determine which bullet I should use that will give me a large danger space, because you dont always have forever to take a shot. I typically would use laser ranger finder and then verify with mil dot but theres not always time for that process especially without a spotter.
What Im doing is using Bryans Max Effective Range to decide the distance for "ethical" hunting shot and have always thought the distance you can almost guarantee POI in a 12in circle then thats acceptable for deer or anything larger. That being said I determine distance for whitetail having 12in vitals or 14-16in for mule deer. I have lots of time behind the scope shooting 600yds and closer and with 10mph wind say 90% of the time I'll hit well into 1.5 MOA, regularly .50 to .75 MOA, and with 20mph within 3 MOA so for a hunting situation any wind over a full value would mean a closer shot. So now using danger space to determine which bullet I should use that will give me a large danger space, because you dont always have forever to take a shot. I typically would use laser ranger finder and then verify with mil dot but theres not always time for that process especially without a spotter.
Re: Danger Space Info Needed
Thinking about using the new hornady 178gr bthp or nosler 200 gr accubond. I just finished loadind a batch of the accubonds so I'll find out soon how they do. I learned to shoot with a 45-70 silhoutte so I prefer the heavier slow bullets. Montanamarine always has had interesting info in that department, and how I got started with the 208gr amax. Appreciate all the help, hopefully I'll get Bryans book in the mail in the next couple days.
Thinking about using the new hornady 178gr bthp or nosler 200 gr accubond. I just finished loadind a batch of the accubonds so I'll find out soon how they do. I learned to shoot with a 45-70 silhoutte so I prefer the heavier slow bullets. Montanamarine always has had interesting info in that department, and how I got started with the 208gr amax. Appreciate all the help, hopefully I'll get Bryans book in the mail in the next couple days.
Re: Danger Space Info Needed
bjax, you understand the problem well...
IMO, 12" vital zone for a whitetail is too large, I would pick 10".
Remember you have to add all the possible errors if you want a first shot hit all the time:
- your real world accuracy with a given rifle/load under certain stress and time limitations, that's a certain spread at a given distance.
- your POI also may change a little in the real world, at least for the first shot, due to environmental conditions (wind, temp., pressure, not ideal shooting position, shooting angle, etc.). The most important factor at mid range (< 600 yds) is horizontal error due to wind, but you can have a vertical wind component too.
- your range estimation
A practical test would be to position 10" targets at random distances in the field (not recording the exact range), walk back (perhaps even do a couple pushups), and then within a time limit put a first shot (accounting for wind for the first time) on it.
bjax, you understand the problem well...
IMO, 12" vital zone for a whitetail is too large, I would pick 10".
Remember you have to add all the possible errors if you want a first shot hit all the time:
- your real world accuracy with a given rifle/load under certain stress and time limitations, that's a certain spread at a given distance.
- your POI also may change a little in the real world, at least for the first shot, due to environmental conditions (wind, temp., pressure, not ideal shooting position, shooting angle, etc.). The most important factor at mid range (< 600 yds) is horizontal error due to wind, but you can have a vertical wind component too.
- your range estimation
A practical test would be to position 10" targets at random distances in the field (not recording the exact range), walk back (perhaps even do a couple pushups), and then within a time limit put a first shot (accounting for wind for the first time) on it.
