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From: gmk@falstaff.MAE.CWRU.EDU (Geoff Kotzar)
Subject: Re: Paxton Question
Organization: /etc/organization

In article <380i0n$> (Bart Bobbit) writes:
#I find it interesting to read the various explanations as to why rifles
#are more accurate than handguns.   Some posted comments are, in reality,
#why rifles are `easier to shoot more accurately' than handguns; not why
#`rifles are more accurate' than handguns.  There is a distinct difference
#between these two situations.
#Wasn't the original issue related to why rifles are more accurate than
#handguns?  Not why rifles are easier to shoot more accurate than handguns;

If the original impetus for this discussion was the Paxton Quigley
writng, I suspect that she is not even aware of the distinction.
Inherent accuracy and practical accuracy are probably one and the
same to the novice.

#If both types of firearms are put in machine rests, the rifle will shoot
#more accurately than the handgun; typically.  And that eliminates sight
#radius, consistant holding, trigger quality, variables in recoil, etc.
#So, why are handguns typically less accurate than rifles?

The first question might be which handguns are we going to talk about?
Bolt action "short rifles" like the XP-100? Why should one of these be
any more or less accurate than the comparable quality long gun?

How about the other single shot actions like the Thompson/Center break
action or one of the falling block actions? I know that the T/C
Contender is at least as accurate, in general, as the T/C rifle. I
haven't worked with any of the falling block single shots or the other
action types that are used or hunting or silhouette competition so I
can't comment on the expected performance of them.

If you start talking about the two most common handguns handgun action
types, revolvers and semi-autos, there are several reasons why getting
rifle-like accuracy from them is difficult. For revolvers, number one
reason is that the chamber is not integral with the barrel. The bullet
is asked to undergo a gymanstic performance not required from rifles.
First the chamber throats may be smaller or larger than the groove
diameter of the barrel. If larger, the bullets slug up to fill the
throat, if they are soft enough to do so, then have to be slugged
back down in the forcing cone. If the bullets are too hard to set
up to fill the throat, they suffer from flame cutting and/or tipping
in the throat. If the throat is smaller than groove diameter the bullet
is swaged down and you can almost give up on serious accuracy.

Add to that the characteristic constriction in the barrel where it is
screwed into the frame. The smallest groove diameter of revolver barrels
occurs at the breech end in the region of the barrel threats. You already
know the effects on inherent accuracy of diameter variations. And I guess
I forgot to mention the obvious: the cylinder always has some angular play.
The bullet does not always enter the barrel in a coaxial fashion. Also the
bullets have significant velocity when they strike the rifling and typically
show some skidding along their length; this is especially true for lead
bullets even up through linotype hardness. Additionally, six shot cylinders
do not have the chambers oriented perfectly uniformly around the cylinder
axis. Shoot groups out of all six chambers and one groups size results;
shoot from only one chamber or the five best and a smaller group results.

In spite of all of these problems, non-premium revlovers like Rugers and
Smiths can be coaxed into shooting 1" 100yd groups regularly provided that
chamber throats are not smaller than groove diameter, not too much larger
than groove diameter, that the barrel constriction at the threads is removed,
and that the proper cast bullets are used. There are people who play at
producing groups that average 1.5 to 1.75 inches at 100 yards with what
might be called "regular" revolvers as opposed to the premium ones like
the Freedom Arms Casulls. Blackie Sleeva, who won the Buckmasters compe-
tition a few years ago, used a Freedom Arms .44 Mag which averaged 2"
groups at 100 yards with the factory loads supplied by the match promoters.
No tinkering, no fussing, no tuning. Off the shelf gun with off the shelf

When it comes to semi-autos, I haven't spent as much time behind them
as I should have but I can think of a couple of things that would effect
their inherent accuracy. First you have three non-rigidily connected
components in the frame, slide and barrel. Include the Beretta designs
and you also have a locking block in there that has to be accounted for.
You have frequently commented that producing small dispersions requires
reproducible orientation of all of the components so it is a wonder that
they shoot as well as they do.

Finally you come to the issue of how much effort the manufacturers put into
each handgun. They are seen as being short range weapons and understandably
only the minimum required effort is expended. Those that are used to hunt
woodchucks at 300+ yards are more finely fitted; those that are primarily
self-defense firearms and need to produce 3" groups at 25 yards are not.
Rifles are seen as long range tools. And no hunter wants to be handicapped
by a rifle that won't shoot to the limit of the cartridge it is chambered
for. What is the useful range of a 94 Winchester in .30-30? 150-175 yards?
And how big is  a deer's vital zone? 6 inches or so? So they have to shoot
groups smaller than 3 or 4 inches at 100 yards.

geoff kotzar

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