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From: bercov@bevsun.bev.lbl.gov (John Bercovitz)
Subject: Re: distance a .22 lr travels
Organization: Lawrence Berkeley Laboratory, California

In article <BxB8BM.3F5@news.cso.uiuc.edu> cs125c51@dcl-nxt31.cso.uiuc.edu
(cs125 student) writes:

#I'm fairly new to shooting .22's, and I have a question about how far they
#really travel. I use CCI mini-mags, hv, and do all of my shooting in the
#direction, a direction I need to shoot in. Now, (that's my Ross Perot
#imitation), on the box it says, "Dangerous to 1 1/2 miles", and I believe that.
#My question: Is that at a shooting angle of 45 degrees? Most of my shooting
#will be at angles of about 30 degrees and lower. Now how far will the bullet
#travel? After traveling a mile, will the terminal velocity really be enough to
#do some damage to a body, both head and non-head areas?

#Can I simply use 1.5 miles as maximum distance traveled at 45 degrees and use
#trig to figure out the rest? How much different is std velocity?

First thing is that you really must have a backstop.  You don't want to
shoot in a direction where you have to constantly monitor a vast area
for occupants, human or otherwise.  Too much responsibility.

That 1.5 miles is a nominal figure and depends on skipping - bullets bounce
or ricochet off flat surfaces and thereby go much further than their
ballistic trajectory alone would indicate.  For 22 rimfire bullets, maximum
ballistic range is found at a muzzle elevation of around 35 degrees, as I
recall.

That 45 degree figure you're thinking of is for a projectile in a vacuum.
In a vacuum, range is (1/g)(v^2)(sin(2 theta)).  So maximum range in a
vacuum is at 45 degrees.  The range in a vacuum for a 1500 fps bullet (how
fast _do_ CCI MiniMags go?) would be 1500^2/32.174 = 13 miles!  And on
the moon it would be 6 times that distance, of course.

I just ran the Sierra ballistic program for a 40 gn bullet with a bc of
.1 and an initial velocity of 1500 fps.  I found that at 1000 yards the
velocity had fallen to 300 or so fps.  This is getting into the sub-
lethal area but I sure as heck wouldn't count on it.

Anyway, this has been fun but you really must have a backstop.

John Bercovitz     (JHBercovitz@lbl.gov)


From: John De Armond
Subject: Re: .22 LR can kill at 1 mile
Organization: Dixie Communications Public Access.  The Mouth of the South.

th2_oate@csd.uwe-bristol.ac.uk (Tom Oates) writes:

#I can't help you regarding the angle of fire. However, I can certify that
#when a box of .22LR states that it can kill or injure someone at a range
#of over a mile - it's not exaggerating. I have read several newspaper accounts
#of people being killed or injured by stray .22LR bullets that were
#fired by some yo-yo who thought they wouldn't have any 'whack' left in
#them after travelling so far. I recall one incident that occurred about
#5 years ago in the UK: A farmer was out 'varminting' with his bolt-action
#in .22LR. He killed a few and went home. Later, the Police came round and
#questioned him about an incident that had happened earlier that afternoon:
#a little girl aged about 7 years old had been playing in her back garden
#(about a mile from the farm) when someone shot her in the side of the head
#with a .22. They took his rifle away to the forensic lab for testing. You
#can probably figure out the rest of this story for yourself. The Police
#were lenient with him because it was an accident and not intentional.
#However, afterwards that man had to live the painful knowledge that he had
#killed a child.

While acknowledging that people have been killed by mere taps to the
temple, the numbers in this case just don't add up.  I decided to
run a ballistic calculation on a .22.    I've used numbers from
Remington high velocity .22 ammo fired from my Model 55 match rifle.
Stingers, et al, will be faster but the bullet is lighter.  Ballistic
coefficient taken from the Speer book for a 40 gr .22 hornet bullet.
#From Frenchu's BALISTIC program:

                                .22 cal bullet
                       (Calculated using Ingalls' table)
      Bullet Weight .........  40 grains   Bullet Caliber ........ 0.224
      Sectional Density ..... 0.114        Coefficient of Form ... 0.791
      Effective Bal. Coeff... 0.144        Bal. Coeff. at STP .... 0.144
      Cross wind ............ 10.0 m.p.h.  Altitude .............. 0    Ft.
      Atmospheric pressure .. 30.00 in.    Temperature ........... 60.0 F

    Range  Velocity  Energy   Momentum  Mx. Ord. Defl.   Drop   Lead   Time
    yards   f.p.s.   ft-lb.   lb.-sec.    in.     in.     in.  in/mph  sec.
       0     1000      88.8    0.1776     0.0     0.0     0.0    0.0   0.000
     239      771      52.8    0.1370    32.8    18.8   120.3   14.5   0.824
     478      611      33.1    0.1085   169.2    76.9   577.2   32.9   1.871
     717      484      20.8    0.0860   493.9   183.3  1568.1   56.2   3.192
     956      383      13.1    0.0681  1146.7   350.7  3402.4   85.5   4.860
    1195      304       8.2    0.0540  2370.1   595.1  6563.6  122.6   6.966

Note that the program would not let me do a calculation out to a mile.
1195 yards is the program limit for this version.  Linearly extrapolating
to 1760 yards (1 mile) puts the velocity at about 200 fps.  I believe these
calculations to be conservative, considering that they are at the limit
of the ballistic algorithm built into BALISTIC.

In any event, a 40 grain bullet is not going to hurt anyone going 200 fps
unless it happened to hit an eye and then it would not kill.  Even 300
fps is not going to do much more than sting.  300 fps is about half the
velocity of an average .22 cal pellet rifle.  Indeed, I have one of
the super cheapo chinese made air rifles that sell for under $15 at
the gun shows that chronos out to almost 700 fps.

The label on the box says RANGE 1 mile.  As computed above, the bullet
will indeed go a mile and still have a tiny bit of velocity left.
I'm having a lot of trouble with the "girl killed a mile away by
farmer with a .22" line.  I've seen similar reports in papers here
in the US.  My inclination is to label it an urban legend (rural legend?),
though I will acknowledge that it is possible for some little girl
somewhere, already predisposed to some fatal problem, dying after being
struck by a .22 bullet, perhaps from a dislodged blood clot or something.
I will NOT accept the claim that someone was killed by bullet penetration
from a .22 fired a mile away.

John


From: John De Armond
Subject: Re: .22 LR can kill at 1 mile
Organization: Dixie Communications Public Access.  The Mouth of the South.

ems@michael.apple.com (E. Michael Smith) writes:

#In article <fpcqs4l@dixie.com> jgd@dixie.com (John De Armond) writes:

##While acknowledging that people have been killed by mere taps to the
##temple, the numbers in this case just don't add up.
#...
##Linearly extrapolating
##to 1760 yards (1 mile) puts the velocity at about 200 fps.

#If a tap can do it, then a 200 fps bullet ought to also ...
#Maybe you need to add a 'probably' in there?

*Sigh*.  Mike is again engaging in his hobby of quibbling about the
trees while missing the forrest.

I used what I considered reasonable but conservative numbers and techniques
in an effort to set off an order of magnitude feel for the numbers.
I forgot about Mike.  Let's zoom in on some particulars.  I used
a ballistic coefficient for the bullet taken from the Speer reloading
manual for a .22 hornet (as I noted)  I felt this coefficient would
be close.  I was wrong, though in the conservative direction.  Someone
emailed me with a quote from some literature that indicates the ballistic
coefficient for a .22 lr bullet ranges from about 0.05 to 0.09.  The
numbers for a range of a mile get too small to treat with any credibility.
Nontheless reruning the calculation using a coefficient of 0.07
and then fitting the data to a curve and extrapolating to a mile, the
computed velocity is about 100 fps.  I'd set the error term on this to
perhaps +25,-100 percent.  In other words, the bullet could very well
have essentially stopped at the range of a mile depending on the
bullet shape.

#This is being a bit absolutist.  I know it is a FOAF story, but the
#friend is a local police Seargent.  He worked a case where a child
#was killed by a BB from a plain old Daisy air rifle.

A BB emits from an air rifle anywhere from about 500 to 800 fps
velocity.

#Believe it, it can, does, and has happened.

Sorry but no.  Until and unless I see first hand evidence such as
the police report, I will NOT believe that anyone can be killed
by a .22 fired a mile away.

#I've shot pellets from a Benjamin pellet pistol into Coke cans and mellons
#with 3 pumps (rather than the usual 10).  I think you will find that a
#40 grain slug at 200 fps does a decent job of punching holes in both
#tin cans and mellons...

Your Benjamin is a rather high powered gun as air pistols go.
They claim about 700 fps as I recall.  Don't forget to square the velocity
when trying to compare the effects of different velocities.

As to observing the effects of pellets, I have plenty of personal
experience.  Like many of my contemporaries, the kids of my neighborhood
and I fought many a pellet gun war.  I've dug more than one BB or
pellet from my skin.  Not fun but certainly not fatal.  And I'm
talking about full bore pellet guns, not gymped down ones.

#If I had a cronograph, I'd measure the velocity of the pelets and report,
#but I don't so I can't.  Can someone with a cronograph do the test?

I do and I believe I noted in my first post that my junky chinese made
air rifle so loose that an air gap can be seen in the breech propels
a pellet to over 700 fps.  (I'll do > 1000 fps if a bit of ether
is sprayed in the compression chamber so it will diesel)

Until someone shows me first hand evidence to the contrary, I stand
by my assertion that a .22 lr bullet fired at a range of a mile cannot
kill a human.  And probably would not even hurt him much.

John



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