[ revised on Mar 21 ]
Sometimes most shots in a sudden handgun fight are misses, or grazing hits.
Hits might first pass through a heavy coat, bone, or safety glass, sometimes
at shallow angles, before causing effective soft-tissue penetration, which is
more important than expansion, fragmentation, or yaw. [per FBI]
A second effective hit on a perp is often necessary; maybe within 2 seconds;
and likewise for any second perp. Sometimes you might want to penetrate
laminated auto door glass. (Windshield penetration is for cops while on duty.)
The drag coefficient of a stable bullet in air is an indicator of penetration potential
through solids. A narrow stable full-jacket bullet has low drag in air, and is more
efficient in penetrating obstructions. They must then have remaining energy to
penetrate soft-tissue at least 5".
Expanding bullets limit soft tissue penetration, and can even prevent penetration.
Yaw (key-holing) reduces energy and penetration, and is no "advantage" unless
there are no obstructions and the target is close. (test those short-barrel guns)
Expanding or flat-nose bullets are not effective from short barrels ( < 2.5")
for 22lr, 32acp, 380acp, and other loads under 180 ftlb (from the actual barrel).
I would never use anything but FMJ in a low-energy pocket gun. (no flat nose)
A 9mm or 357 are different, but they tend to be too heavy and too large.
Maybe a 22wmr from a 4" barrel is good enough for flat/soft points.
(I will test in poplar cylinders someday, using 50gr subsonics if I can get them)
The 25acp should not be chosen for personal defense; it's just too weak through
leather and bone. A 22lr-rn-hv can be effective if fired from a semi-auto barrel
that is least a 3" long, based on my tests on poplar wood.
- - - - - - - - - - - - - - - -
In 380 bullets, the center of pressure during yaw (pressure from air, leather, bone)
is substantially closer to the center of gravity than for the 32acp.
For a given barrel length, the 380 is less stable through all media, and a
short barrel increases this relative instability.
I saw a thread about frequent keyholing from a popular "high-end" pocket gun.
Their product site does not even reveal the barrel length. (which is 2.1").
.
Monday, December 28, 2009
My Carry for Routine Days
Other mods are attached to https://sites.google.com/site/concealedgun/
Would prefer KT PF-9 or Kahr PM-9, but those are a bit bulky, and 9 is too much for wife.
(Will consider Taurus PT-738, .380 fmj, if it proves reliable in reports, but for me the 380
pocket guns don't really beat a P-32 when balancing several factors, including noise.)
pocket guns don't really beat a P-32 when balancing several factors, including noise.)
(I think a 22mag needs a 4" barrel to penetrate coat, bone, and 6" of soft tissue from 10 feet.)
.Tuesday, December 1, 2009
Don't Try to Fix SW380 or SW9
(Updated April 2011)
Regarding the ill-fated Sigma compacts with the pinch-release mags . . .
There are other lines of various SW "Sigma" designs still produced;
I don't know about them, just the two models discontinued in 2001.
Around 1995, Smith introduced Sigma Compacts sw380/sw9m, mainly as backup
guns for law enforcement. .I hope LEO is rid of them by now, but they show
up in at least one list of approved backup/off-duty guns.
I hope there was no death or serious wound resulting from failures to fire.
They were cheap, small, and light (14oz empty), with no protruding features,
except the prominent front corners. They were striker guns, like Glock, and
the operation was too similar; they lost a patent suit by Glock.
I bought a used SW380 at a gun show, knowing little except that it was small,
light, easy to rack for my wife, and a name brand. .It has been a major waste
of time to try to make it work, and it's another serious blot on any reputation
Smith still has. [see "The Dark Side of Smith & Wesson" by Chuck Hawks,
Dec 2008. www.chuckhawks.com/smith-wesson_dark.htm]
When I installed a "lighter" Wolf target spring, it was much longer than
the spring that was in my used sw380. This is part of the light-strike problem.
But even with the Wolf spring, and extensive careful work, it will not fire
more than three in six rounds, even after shaving firing pin surfaces that
might drag on the interlock spool, and even after testing without the spool.
I dealt with every conceivable factor in battery, mechanisms, slam-fire block,
and alignments; and I took material off a dozen surfaces, even the impact nose.
I even used a punch to deform a cartridge centering wall to better align primers
with the firing pin.
Smith now has the 380 manual on their website, but they still want you to send
the gun in for striker part replacement. The striker is very light, so if the
assembly is not right, the impact is light. I think the problem is that the
striker, which combines a hammer and firing pin function, is too light, even
without and dirt, grease, or excess drag.
The slide is cast or MIM soft alloy, with a steel breach face cast or pressed
into the soft slide. What I read is that some have been good guns, and others
junk, like mine.
I would not pay ten cents for another one, since it might not fire when needed.
And I am very reluctant to buy another used gun at a gun show, or any Smith.
.
Regarding the ill-fated Sigma compacts with the pinch-release mags . . .
There are other lines of various SW "Sigma" designs still produced;
I don't know about them, just the two models discontinued in 2001.
Around 1995, Smith introduced Sigma Compacts sw380/sw9m, mainly as backup
guns for law enforcement. .I hope LEO is rid of them by now, but they show
up in at least one list of approved backup/off-duty guns.
I hope there was no death or serious wound resulting from failures to fire.
They were cheap, small, and light (14oz empty), with no protruding features,
except the prominent front corners. They were striker guns, like Glock, and
the operation was too similar; they lost a patent suit by Glock.
I bought a used SW380 at a gun show, knowing little except that it was small,
light, easy to rack for my wife, and a name brand. .It has been a major waste
of time to try to make it work, and it's another serious blot on any reputation
Smith still has. [see "The Dark Side of Smith & Wesson" by Chuck Hawks,
Dec 2008. www.chuckhawks.com/smith-wesson_dark.htm]
When I installed a "lighter" Wolf target spring, it was much longer than
the spring that was in my used sw380. This is part of the light-strike problem.
But even with the Wolf spring, and extensive careful work, it will not fire
more than three in six rounds, even after shaving firing pin surfaces that
might drag on the interlock spool, and even after testing without the spool.
I dealt with every conceivable factor in battery, mechanisms, slam-fire block,
and alignments; and I took material off a dozen surfaces, even the impact nose.
I even used a punch to deform a cartridge centering wall to better align primers
with the firing pin.
Smith now has the 380 manual on their website, but they still want you to send
the gun in for striker part replacement. The striker is very light, so if the
assembly is not right, the impact is light. I think the problem is that the
striker, which combines a hammer and firing pin function, is too light, even
without and dirt, grease, or excess drag.
The slide is cast or MIM soft alloy, with a steel breach face cast or pressed
into the soft slide. What I read is that some have been good guns, and others
junk, like mine.
I would not pay ten cents for another one, since it might not fire when needed.
And I am very reluctant to buy another used gun at a gun show, or any Smith.
.
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