MODERN REVOLVERS
    Revolvers were the first of the "Modern" handguns developed in the
 last century and were long ago brought to a state of near perfection.
 They have somewhat lost popularity because of the current obsession with
 large capacity semi-autos.  This is unfortunate because revolvers still
 are more reliable, safer to handle and more accurate than semi-autos in
 general.  Trading reliability for a large magazine may not be the wisest
 course in a purely self defense weapon.

   The first and most obvious place to start when checking out a revolver
 is the "indexing".  This term is used to indicate the accuracy of the
 alignment of each cylinder with the bore.

                             INDEXING
   To check this gunsmiths use a "range rod", usually a brass tube which
 fits the bore tightly and is inserted into the muzzle to the full depth
 of each chamber in the cylinder as it locked in place by the "stop".
 This is the part that rises into the locking notch on the cylinder from
 the frame just below the cylinder.  This is the typical pattern of modern
 revolvers.

                            THE STOP
   The range rod, which fits the borrel bore tightly, must pass freely
 into each cylinder without the slightest contact of the chamber. To do
 this two conditions must simultaneously exist.  With the trigger held
 back the stop must lock the cylinder tightly to prevent rotation.
 Allowing the slightest movement will disturb the indexing.  The other
 condition required is that the indexing itself must have been cut by
 precision machinery so that each bullet is started into the mouth of
 the barrel in perfect alignment.

                         THE CYLINDER CHAMBERS
  The exit side of each cylinder chamber must not be oversize. They must
 fit the bullet closely to prevent "cocking" or "tilting".  This short
 distance the bullet must travel corresponds to the "throat"area in a
 rifle.  With tremendous gas pressures building behind the bullet as it
 accelerates across this space it must be held in alignment and fit very
 tight to minimize escape of gases around it.  Misalignment caused by a
 loose fit results in distorted bullets with irregular bases and erratic
 flight upon leaving the muzzle, the very same conditions serious rifle
 shooters try to avoid.

                         TRANSITION TO THE BARREL
  The gap between the cylinder and the barrel must be maintained very
 close yet allow for the buildup of lead, jacket material and combustion
 products. A gap of six to ten thousandths of an inch is typical and can
 be observed as a tiny slit when held up to the light with the trigger
 pulled tightly.

                        THE FORCING CONE
  The entrance to the barrel from each chamber is the "forcing cone".
 This is actually the bore of the barrel reamed out to a funnel shape
 to enable the bullet to start into the rifling easily without "shaving".
 Too deep a cone or too wide an angle may allow the bullet to tip over
 before engaging the rifling, thus again there is the possibility of the
  bullet base being distorted and affecting accuracy.

                       MANUFACTURING TOLERANCES
  Revolver manufacturers building utility pistols without supreme accuracy
 in mind allow greater tolerances in the chamber exit and entrance to the
 barrel. This does help in a utility pistol and allows them to be reliable
 even when poorly cared for.   True target revolvers must be built to much
 closer tolerances in the points we have covered so far and may require
 more comprehensive maintenance to maintain accuracy and reliability.

                            TIMING
   Up to this point we have only considered indexing.  The cylinder is
 turned into each index position by the "hand".  On most modern revolvers
 the hand is a pawl pivoted on the upper part of the trigger.  It rises
 through a slot in the breech face to engage notches on a circular ratchet
 called a "spider".  This spider usually serves a dual function of aiding
 in the turning and also in spent cartridge extraction.  Wear of the hand
 and poor machining of the spider will affect what is called "timing".
 Poor or late timing may result in the cylinder not being in alignment
 when the hammer drops. This misalignment will distort the bullet as it
 passes from the cylinder to the barrel.  Discharge of shaved particles
 and excess hot gases through the gap also result. Accuracy is not helped
 by distorted bullets.

                         THE BARREL
   The barrel itself should have clean, sharp rifling. The more important
 condition however is the size of the bore. Oversized bores will lead to
 gas escape around the bullet and tipping as well as possible stripping
 out of the rifling. The muzzle must be as perfectly square with the base
 of the bullet as possible when it exits. Uneven escape of gas may tip
 the bullet as it exits resulting in erratic flight and poor grouping.
 This final exact finishing of the muzzle is called the "crown".

                         THE TRIGGER AND SIGHTS
   Since the trigger and sights are so obvious it is not necessary to
 spend much time and energy in discussing them.  Sights are easy to
 understand and should be satisfactory to the user. The trigger must be
 easy and consistent to release without undue pressure but not light
 enough to be dangerous.