"Tarver Engineering" wrote...
No John Weiss, it is you that changed the subject, one having to do with the
striking the engine compressor with a sholder fired 50 cal. I do wish you
would work on your reading and comprehenbsion, Weiss.
Hmmm... Let's look up the thread...
From: "Tarver Engineering"
Sent: Saturday, August 16, 2003 6:28 PM
Even with a lot of skill, you aren't going to hit a flying 747 engine with a
50 cal, except by luck.
From: "John R Weiss"
Sent: Saturday, August 16, 2003 3:14 PM
If the target is an airplane, it would be more a matter of skill than luck.
From: "Tarver Engineering"
Sent: Saturday, August 16, 2003 12:15 PM
Hitting a target moving at 120 kts with a bullet would be pure luck.
From: "Jim Yanik"
Sent: Saturday, August 16, 2003 11:24 AM
But the chance of hitting something critical still is very small,and the
frontal area of an airplane is still pretty small and a moving target.
From: "John Keeney"
Sent: Friday, August 15, 2003 11:47 PM
Aim for the cockpit from along the flight path: high probability of
escape if the plane doesn't fall on you and if it does, well, a plane
load of tourist seems worth dyeing for to a lot of jihadist.
From: "Jim Yanik"
Sent: Friday, August 15, 2003 8:30 PM
Hitting a passenger jet with a .50BMG (single shot or semi-auto,10 round
magazine)will not be easy,and will have little effect,as hitting something
critical is unlikely.Probably go in one side and out the other,very little
damage.
From: "Peter Glasų"
Sent: Friday, August 15, 2003 11:00 AM
Or a few men armed with 0.50 cal. sniper rifles -
readily available in the US.
The top of this thread, where the "Igla" discussion switched to rifles, said
absolutely nothing about engine compressors. As a matter of fact, your message
of 10:42 AM today is the FIRST that mentions an engine compressor at all!
My reading and comprehension are fine. I doubt yours, though.
Nope, the discussion is tied to a URL for a specific exploding ammunition in
50 calibre. The fact that you can't read is not a reason for you to become
insulting, Weiss.
I don't know where you got this "URL for a specific exploding ammunition" stuff!
Peter Glaso's Aug 15, 11:00 AM message was the first that mentioned rifles at
all. Nowhere in the thread is there any mention of exploding ammunition or a
URL reference to it.
Again, I can read just fine. If you want to be insulted, I can't stop you.
First you can't read and then you have a brain fart.
1000 yards is about the effective range of the weapon, on a stationary
target.
So, the stated range is well inside the effective range -- not a problem!
Big problem, as the flying airplane is well outside the parameters of
"stationary".
I have not found a definition of "effective range" for rifle ammunition that is
limited to stationary targets:
What is the definition of Maximum Effective Range?
The greatest distance at which the weapon may be expected to inflict
casualties
http://www.armystudyguide.com/m16/studyguide.htm
MAXIMUM EFFECTIVE RANGE- The greatest distance at which a weapon may be
expected to fire accurately to inflict damage or casualties.
http://www.tpub.com/maa/85.htm
EFFECTIVE RANGE
THAT RANGE AT WHICH A WEAPON OR WEAPONS SYSTEM HAS A FIFTY PERCENT
PROBABILITY OF HITTING A TARGET
http://members.aol.com/usmilbrats/glossary/e.htm
effective range means the greatest distance a projectile will travel with
accuracy
http://www.directives.doe.gov/pdfs/n...y/termsk_r.pdf and
http://www.fs.fed.us/r3/coronado/scr...ess/rgrisk.htm
However, a comprehensive discussion of calculating lead for moving targets can
be found at
http://www.alpharubicon.com/leo/mildot.htm. According to the
writer, a .308 is an "effective" sniper round against moving targets at 600-800
yards (listed effective range is 800-1000 yards, according to
http://www.snipercentral.com/308.htm). This translates to an effective range
for moving targets that is 75-80% that for stationary targets, and is consistent
with the effective ranges of the Chieftain's 120mm gun against moving and
stationary targets (2000 m vs 3000 m, or 66%;
http://call.army.mil/products/newsltrs/90-8/90-8ch9.htm); an M72 antitank rocket
(165 meters vs 200 meters, or 82%;
http://www.isayeret.com/weapons/rockets/law/law.htm); or an RPG-7 (300 m vs 500
m, or 60%;
http://www.sof-land.net/index.php?bo...wpguide&page=3). It makes
complete sense that the .50 BMG should easily be "effective" against a moving
target at 300 yards -- only 16% of its listed effective range (1800 meters
against equipment size targets;
http://www.fas.org/man/dod-101/sys/land/m82.htm).
FWIW, "The M82A2 was obviously designed as a cheap anti-helicopter weapon,
suitable for use against highly mobile targets when fired from the shoulder."
(
http://world.guns.ru/sniper/sn02-e.htm), so the suitability of .50 BMG weapons
in their current form, against moving targets, has been explored in their
development history.
Lead becomes the problem and I think you know I lowballed the airspeed.
The lead-computation formulae in the alpharubicon discussion above (as well as
others) shows us that lead can be computed in advance for known or expected
targets. Besides, the airspeed is not too low for a small airliner. Further
the airspeed of a 747 on final approach (130-160 knots) or just after takeoff
(140-185 knots) is in the same order of magnitude. At the outside limit (185
knots instead of 120), the time in view for any point of the airplane (using
previously presented parameters) is still 3.65 seconds. A single sniper could
still easily place 4 rounds of a 5-round magazine into the center fuselage or
wing section in that time.
I have a real problem with the idea of bracketing shots from a sholder fired
50 caliber at a target traveling at 3 miles a minute.
I don't doubt that for a second!
No, the thread is specificly about a sholder fired 50 calibre, of which a
single shot and a semi automatic are available to the public, using specific
ammunition and striking the compressor face.
Hardly! None of the initiators of the ".50 cal./.50BMG thread limited the
discussion to "shoulder fired" or "specific ammunition"; a compressor face never
entered the discussion until your mention immediately above.
Of course, if we change the subject to some completely different set of
parameters, Weiss might be correct. A tripod mounted 50 calibre machine gun
could do the job.
No specific parameters were presented other than round, range to target and
airspeed. I merely selected a representative set of parameters as an example
exercise for analysis. The parameters are suitable to a bipod-mounted .50 BMG
"sniper rifle" such as:
Barrett M82A1A equipped with bipod
http://www.fas.org/man/dod-101/sys/land/m82.htm
Barrett M95
http://www.biggerhammer.net/barrett/
EDM Windrunner XM107 with M14 bipod
1/2 MOA accuracy
http://www.50-bmg.com/50.htm
I think Weiss has us back to a Humvee mounted machine gun.
Not yet, though that would substantially increase the number of hits...
Of course, Weiss has a habbit of changing the subject such that what he
wrote previously isn't as luney as when it was penned. Educational though.
No change in subject here!
I am more than happy to provide you with the education you must have previously
missed.