After reading responses about the two .22 revolvers only 1 is a good
candidate for what I want to do. So now comes the machining part.
First, measuring the cylinder shows that the ends are not parallel.
the ends may not be square to the central hole either. This hole is
tapered. On the back end the hole measures .191 and at the front .188.
the rod that goes through it measures .185 at the back and .186 at the
front. The hole in the frame at the front measures .191. At the tip of
the rod the diameter is reduced to .137. The hole in the pistol is
..142. It all seems pretty sloppy. I haven't checked the accuracy of
the hole spacing or the accuracy of the indexing teeth. It seems that
as long as the teeth all have the same relationship to their
respective holes (chambers?) then the chambers should all line up with
the barrel if one does. My proposed plan of action is to first remove
the taper from the central hole and then make sure the cylinder faces
are parallel and square to the central hole. Then, make the new rod
that goes through the cylinder. The rod will be .190 diameter with the
smaller diameter at the front being .141. I will make a dummy cylinder
out of brass and charge the ends with fine abrasive to lap the faces
in the frame where the cylinder contacts square to the cylinder. Next,
the faces on the teeth where they cantact the frame will be checked
for squareness and made square if need be. After this is done the
headspace needs to be checked. If too small I will face enough off the
back end of the cylinder to set the headspace correctly. What is the
proper headspace? Is there a way to determine this for any revolver?
After all that then the front of the cylinder where the play is set
will need to be changed. This little spud is .246 dia and protrudes
..108. I am going to counterbore the cylinder .250 dia. by .250 deep
and press in a short tube that's .180 I.D. by ..400 long before the
cylinder I.D. has the taper removed. Then when the frame is ready I'll
measure the inside dimension of the frame and make the cylinder .001
shorter. Finally, after all that's done, the barrel will be removed
and modified to set the proper clearance between the cylinder and the
barrel.
ERS

The standard rim thickness for the 22 rf is .044" Therefore the headspace
in a revolver needs to be .044" + enough to allow free rotation of the
cylinder. I don't have the industry standard dimensions to hand, but
..048"-.050" should be plenty. A real headspace gauge looks like a short
cartridge case with the proper thickness rim machined on it. They are
commonly made in Go and NoGo sizes. In practice you can use a cartridge and
a feeler gauge since the actual dimension is not too critical in a revolver.

BTW, the ratchet teeth do not determine indexing. It is controlled by the
cylinder bolt in the bottom of the frame window locking into the bolt
notches on the cylinder OD. Thus, the indexing accuracy is determined by
the accuracy of the cylinder machining when it was made.

The rest of your plan sounds good to me.

Randy


"Eric R Snow" wrote in message
...
After reading responses about the two .22 revolvers only 1 is a good
candidate for what I want to do. So now comes the machining part.
First, measuring the cylinder shows that the ends are not parallel.
the ends may not be square to the central hole either. This hole is
tapered. On the back end the hole measures .191 and at the front .188.
the rod that goes through it measures .185 at the back and .186 at the
front. The hole in the frame at the front measures .191. At the tip of
the rod the diameter is reduced to .137. The hole in the pistol is
.142. It all seems pretty sloppy. I haven't checked the accuracy of
the hole spacing or the accuracy of the indexing teeth. It seems that
as long as the teeth all have the same relationship to their
respective holes (chambers?) then the chambers should all line up with
the barrel if one does. My proposed plan of action is to first remove
the taper from the central hole and then make sure the cylinder faces
are parallel and square to the central hole. Then, make the new rod
that goes through the cylinder. The rod will be .190 diameter with the
smaller diameter at the front being .141. I will make a dummy cylinder
out of brass and charge the ends with fine abrasive to lap the faces
in the frame where the cylinder contacts square to the cylinder. Next,
the faces on the teeth where they cantact the frame will be checked
for squareness and made square if need be. After this is done the
headspace needs to be checked. If too small I will face enough off the
back end of the cylinder to set the headspace correctly. What is the
proper headspace? Is there a way to determine this for any revolver?
After all that then the front of the cylinder where the play is set
will need to be changed. This little spud is .246 dia and protrudes
.108. I am going to counterbore the cylinder .250 dia. by .250 deep
and press in a short tube that's .180 I.D. by ..400 long before the
cylinder I.D. has the taper removed. Then when the frame is ready I'll
measure the inside dimension of the frame and make the cylinder .001
shorter. Finally, after all that's done, the barrel will be removed
and modified to set the proper clearance between the cylinder and the
barrel.
ERS

On Mon, 12 Sep 2005 11:22:17 -0500, "R. O'Brian"
wrote:

The standard rim thickness for the 22 rf is .044" Therefore the headspace
in a revolver needs to be .044" + enough to allow free rotation of the
cylinder. I don't have the industry standard dimensions to hand, but
.048"-.050" should be plenty. A real headspace gauge looks like a short
cartridge case with the proper thickness rim machined on it. They are
commonly made in Go and NoGo sizes. In practice you can use a cartridge and
a feeler gauge since the actual dimension is not too critical in a revolver.

BTW, the ratchet teeth do not determine indexing. It is controlled by the
cylinder bolt in the bottom of the frame window locking into the bolt
notches on the cylinder OD. Thus, the indexing accuracy is determined by
the accuracy of the cylinder machining when it was made.

The rest of your plan sounds good to me.

Randy
I see that cylinder bolt now that you told me about it. It not only
stops rotation but also keeps the cylinder from moving fore and aft.
From careful examination it appears that the cylinder bolt is part of
thr trigger. And the radius on the end of the bolt matches the radii
in the cylinder notches. So I need to make sure that when measuring
the trigger is pulled so that the cylinder will be in the proper
position.
ERS

"Eric R Snow" wrote in message
.. .
After reading responses about the two .22 revolvers only 1 is a good
candidate for what I want to do. So now comes the machining part.
First, measuring the cylinder shows that the ends are not parallel.
the ends may not be square to the central hole either. This hole is
tapered. On the back end the hole measures .191 and at the front .188.
the rod that goes through it measures .185 at the back and .186 at the
front. The hole in the frame at the front measures .191. At the tip of
the rod the diameter is reduced to .137. The hole in the pistol is
.142. It all seems pretty sloppy. I haven't checked the accuracy of
the hole spacing or the accuracy of the indexing teeth. It seems that
as long as the teeth all have the same relationship to their
respective holes (chambers?) then the chambers should all line up with
the barrel if one does. My proposed plan of action is to first remove
the taper from the central hole and then make sure the cylinder faces
are parallel and square to the central hole. Then, make the new rod
that goes through the cylinder. The rod will be .190 diameter with the
smaller diameter at the front being .141. I will make a dummy cylinder
out of brass and charge the ends with fine abrasive to lap the faces
in the frame where the cylinder contacts square to the cylinder. Next,
the faces on the teeth where they cantact the frame will be checked
for squareness and made square if need be. After this is done the
headspace needs to be checked. If too small I will face enough off the
back end of the cylinder to set the headspace correctly. What is the
proper headspace? Is there a way to determine this for any revolver?
After all that then the front of the cylinder where the play is set
will need to be changed. This little spud is .246 dia and protrudes
.108. I am going to counterbore the cylinder .250 dia. by .250 deep
and press in a short tube that's .180 I.D. by ..400 long before the
cylinder I.D. has the taper removed. Then when the frame is ready I'll
measure the inside dimension of the frame and make the cylinder .001
shorter. Finally, after all that's done, the barrel will be removed
and modified to set the proper clearance between the cylinder and the
barrel.
ERS

On Mon, 12 Sep 2005 09:48:46 -0700, Eric R Snow
wrote:

On Mon, 12 Sep 2005 11:22:17 -0500, "R. O'Brian"
wrote:

The standard rim thickness for the 22 rf is .044" Therefore the headspace
in a revolver needs to be .044" + enough to allow free rotation of the
cylinder. I don't have the industry standard dimensions to hand, but
.048"-.050" should be plenty. A real headspace gauge looks like a short
cartridge case with the proper thickness rim machined on it. They are
commonly made in Go and NoGo sizes. In practice you can use a cartridge and
a feeler gauge since the actual dimension is not too critical in a revolver.

BTW, the ratchet teeth do not determine indexing. It is controlled by the
cylinder bolt in the bottom of the frame window locking into the bolt
notches on the cylinder OD. Thus, the indexing accuracy is determined by
the accuracy of the cylinder machining when it was made.

The rest of your plan sounds good to me.

Randy
I see that cylinder bolt now that you told me about it. It not only
stops rotation but also keeps the cylinder from moving fore and aft.
From careful examination it appears that the cylinder bolt is part of
thr trigger. And the radius on the end of the bolt matches the radii
in the cylinder notches. So I need to make sure that when measuring
the trigger is pulled so that the cylinder will be in the proper
position.
ERS

As I posted before...pull the hammer back and hold it while pulling
the trigger. This loads the entire system, pawls, sear, etc

Gunner


"Eric R Snow" wrote in message
. ..
After reading responses about the two .22 revolvers only 1 is a good
candidate for what I want to do. So now comes the machining part.
First, measuring the cylinder shows that the ends are not parallel.
the ends may not be square to the central hole either. This hole is
tapered. On the back end the hole measures .191 and at the front .188.
the rod that goes through it measures .185 at the back and .186 at the
front. The hole in the frame at the front measures .191. At the tip of
the rod the diameter is reduced to .137. The hole in the pistol is
.142. It all seems pretty sloppy. I haven't checked the accuracy of
the hole spacing or the accuracy of the indexing teeth. It seems that
as long as the teeth all have the same relationship to their
respective holes (chambers?) then the chambers should all line up with
the barrel if one does. My proposed plan of action is to first remove
the taper from the central hole and then make sure the cylinder faces
are parallel and square to the central hole. Then, make the new rod
that goes through the cylinder. The rod will be .190 diameter with the
smaller diameter at the front being .141. I will make a dummy cylinder
out of brass and charge the ends with fine abrasive to lap the faces
in the frame where the cylinder contacts square to the cylinder. Next,
the faces on the teeth where they cantact the frame will be checked
for squareness and made square if need be. After this is done the
headspace needs to be checked. If too small I will face enough off the
back end of the cylinder to set the headspace correctly. What is the
proper headspace? Is there a way to determine this for any revolver?
After all that then the front of the cylinder where the play is set
will need to be changed. This little spud is .246 dia and protrudes
.108. I am going to counterbore the cylinder .250 dia. by .250 deep
and press in a short tube that's .180 I.D. by ..400 long before the
cylinder I.D. has the taper removed. Then when the frame is ready I'll
measure the inside dimension of the frame and make the cylinder .001
shorter. Finally, after all that's done, the barrel will be removed
and modified to set the proper clearance between the cylinder and the
barrel.
ERS


"Pax Americana is a philosophy. Hardly an empire.
Making sure other people play nice and dont kill each other (and us)
off in job lots is hardly empire building, particularly when you give
them self determination under "play nice" rules.

Think of it as having your older brother knock the **** out of you
for torturing the cat." Gunner

According to R. O'Brian :
The standard rim thickness for the 22 rf is .044" Therefore the headspace
in a revolver needs to be .044" + enough to allow free rotation of the
cylinder. I don't have the industry standard dimensions to hand, but
.048"-.050" should be plenty. A real headspace gauge looks like a short
cartridge case with the proper thickness rim machined on it. They are
commonly made in Go and NoGo sizes. In practice you can use a cartridge and
a feeler gauge since the actual dimension is not too critical in a revolver.

BTW, the ratchet teeth do not determine indexing. It is controlled by the
cylinder bolt in the bottom of the frame window locking into the bolt
notches on the cylinder OD. Thus, the indexing accuracy is determined by
the accuracy of the cylinder machining when it was made.

But the ratchet teeth need to move the cylinder to the proper
point so the "cylinder bolt" will drop into it. If the notch is not in
line, then the hammer will fall with the cylinder out of line. If it is
a *lot* out of line, the firing pin won't hit the primer, so there will
be no real problem (assuming that your life is not depending on the
thing firing when the trigger is pulled), but if it is just slightly out
of line, then the cartridge will fire, and it will (at best) spit a lot
of lead out one side or the other. With something as small as a .22,
and with as large a sensitive primer area (the whole rim), I could see
it being out of time by 1/2 the diameter of the bullet, which could be
quite nasty.

So -- make sure that when you are done, the locking lug
("cylinder bolt" above) falls cleanly into the index notch -- *before*
you ever put any ammunition in it.

Check what happens both with slow cocking and fast (as with
fast, it is likely that the momentum of the cylinder will spin it a bit
more, so the locking lug will drop in anyway as the notch tries to spin
past it).

And -- if it is double action -- see whether the behavior is the
same when it is driven by the trigger instead of the hammer (as wear in
the linkage between them could cause shifts in the timing, depending on
just how the indexing pawl is driven. Those that I have seen were
directly driven by the hammer, but a worn or sloppy bearing pin for the
hammer to rotate on could shift in different directions, depending on
whether the hammer is being pulled back by a thumb, or cammed back by a
trigger.)

So -- make sure that you know what it is going to do
mechanically *before* you let it fire live ammo.

Good Luck,
DoN.
--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

In article , DoN. Nichols
wrote:

According to R. O'Brian :
The standard rim thickness for the 22 rf is .044" Therefore the headspace
in a revolver needs to be .044" + enough to allow free rotation of the
cylinder. I don't have the industry standard dimensions to hand, but
.048"-.050" should be plenty. A real headspace gauge looks like a short
cartridge case with the proper thickness rim machined on it. They are
commonly made in Go and NoGo sizes. In practice you can use a cartridge and
a feeler gauge since the actual dimension is not too critical in a revolver.

BTW, the ratchet teeth do not determine indexing. It is controlled by the
cylinder bolt in the bottom of the frame window locking into the bolt
notches on the cylinder OD. Thus, the indexing accuracy is determined by
the accuracy of the cylinder machining when it was made.

But the ratchet teeth need to move the cylinder to the proper
point so the "cylinder bolt" will drop into it. If the notch is not in
line, then the hammer will fall with the cylinder out of line. If it is
a *lot* out of line, the firing pin won't hit the primer, so there will
be no real problem (assuming that your life is not depending on the
thing firing when the trigger is pulled), but if it is just slightly out
of line, then the cartridge will fire, and it will (at best) spit a lot
of lead out one side or the other. With something as small as a .22,
and with as large a sensitive primer area (the whole rim), I could see
it being out of time by 1/2 the diameter of the bullet, which could be
quite nasty.

So -- make sure that when you are done, the locking lug
("cylinder bolt" above) falls cleanly into the index notch -- *before*
you ever put any ammunition in it.

Check what happens both with slow cocking and fast (as with
fast, it is likely that the momentum of the cylinder will spin it a bit
more, so the locking lug will drop in anyway as the notch tries to spin
past it).

And -- if it is double action -- see whether the behavior is the
same when it is driven by the trigger instead of the hammer (as wear in
the linkage between them could cause shifts in the timing, depending on
just how the indexing pawl is driven. Those that I have seen were
directly driven by the hammer, but a worn or sloppy bearing pin for the
hammer to rotate on could shift in different directions, depending on
whether the hammer is being pulled back by a thumb, or cammed back by a
trigger.)

So -- make sure that you know what it is going to do
mechanically *before* you let it fire live ammo.

Agree with all of the above. It can be a right fiddly PITA to do, too.
However, if you're only making one cylinder, or a couple, for the same
frame, here's what I did.

First, I cut the indexing star and made sure I had that right. Second,
I cut the locking bolt recesses and checked the cylinder locked up
tight. At this point I had a solid cylinder with indexing star and
locking bolts. I'd sorted end shake, headspace etc etc as well.

Then I made an accurate threaded barrel stub with reamed slip fit hole
on centre. Custom made centre punch to fit the bore. Remove barrel,
substitute barrel stub, bring cylinder to lockup, then use the punch to
mark the cylinder face. Ditto for all chambers. Worth doing it a couple
of times, not being too heavy handed, to check repeatability.

Now you *know* the centre of each chamber, at the important end - where
it lines up with the barrel. Pick up the centres, drill/bore/ream each
chamber. For a 22, using 4140, call it done.

Worked for me.

PDW

On Tue, 13 Sep 2005 17:48:03 +0100, Peter Wiley
wrote:

In article , DoN. Nichols
wrote:

According to R. O'Brian :
The standard rim thickness for the 22 rf is .044" Therefore the headspace
in a revolver needs to be .044" + enough to allow free rotation of the
cylinder. I don't have the industry standard dimensions to hand, but
.048"-.050" should be plenty. A real headspace gauge looks like a short
cartridge case with the proper thickness rim machined on it. They are
commonly made in Go and NoGo sizes. In practice you can use a cartridge and
a feeler gauge since the actual dimension is not too critical in a revolver.

BTW, the ratchet teeth do not determine indexing. It is controlled by the
cylinder bolt in the bottom of the frame window locking into the bolt
notches on the cylinder OD. Thus, the indexing accuracy is determined by
the accuracy of the cylinder machining when it was made.

But the ratchet teeth need to move the cylinder to the proper
point so the "cylinder bolt" will drop into it. If the notch is not in
line, then the hammer will fall with the cylinder out of line. If it is
a *lot* out of line, the firing pin won't hit the primer, so there will
be no real problem (assuming that your life is not depending on the
thing firing when the trigger is pulled), but if it is just slightly out
of line, then the cartridge will fire, and it will (at best) spit a lot
of lead out one side or the other. With something as small as a .22,
and with as large a sensitive primer area (the whole rim), I could see
it being out of time by 1/2 the diameter of the bullet, which could be
quite nasty.

So -- make sure that when you are done, the locking lug
("cylinder bolt" above) falls cleanly into the index notch -- *before*
you ever put any ammunition in it.

Check what happens both with slow cocking and fast (as with
fast, it is likely that the momentum of the cylinder will spin it a bit
more, so the locking lug will drop in anyway as the notch tries to spin
past it).

And -- if it is double action -- see whether the behavior is the
same when it is driven by the trigger instead of the hammer (as wear in
the linkage between them could cause shifts in the timing, depending on
just how the indexing pawl is driven. Those that I have seen were
directly driven by the hammer, but a worn or sloppy bearing pin for the
hammer to rotate on could shift in different directions, depending on
whether the hammer is being pulled back by a thumb, or cammed back by a
trigger.)

So -- make sure that you know what it is going to do
mechanically *before* you let it fire live ammo.

Agree with all of the above. It can be a right fiddly PITA to do, too.
However, if you're only making one cylinder, or a couple, for the same
frame, here's what I did.

First, I cut the indexing star and made sure I had that right. Second,
I cut the locking bolt recesses and checked the cylinder locked up
tight. At this point I had a solid cylinder with indexing star and
locking bolts. I'd sorted end shake, headspace etc etc as well.

Then I made an accurate threaded barrel stub with reamed slip fit hole
on centre. Custom made centre punch to fit the bore. Remove barrel,
substitute barrel stub, bring cylinder to lockup, then use the punch to
mark the cylinder face. Ditto for all chambers. Worth doing it a couple
of times, not being too heavy handed, to check repeatability.

Now you *know* the centre of each chamber, at the important end - where
it lines up with the barrel. Pick up the centres, drill/bore/ream each
chamber. For a 22, using 4140, call it done.

Worked for me.

PDW


Sweet!! GOOD idea. Ill put that in my "Tips" book.

Gunner

"Pax Americana is a philosophy. Hardly an empire.
Making sure other people play nice and dont kill each other (and us)
off in job lots is hardly empire building, particularly when you give
them self determination under "play nice" rules.

Think of it as having your older brother knock the **** out of you
for torturing the cat." Gunner

On Tue, 13 Sep 2005 17:48:03 +0100, Peter Wiley
wrote:

In article , DoN. Nichols
wrote:

According to R. O'Brian :
The standard rim thickness for the 22 rf is .044" Therefore the headspace
in a revolver needs to be .044" + enough to allow free rotation of the
cylinder. I don't have the industry standard dimensions to hand, but
.048"-.050" should be plenty. A real headspace gauge looks like a short
cartridge case with the proper thickness rim machined on it. They are
commonly made in Go and NoGo sizes. In practice you can use a cartridge and
a feeler gauge since the actual dimension is not too critical in a revolver.

BTW, the ratchet teeth do not determine indexing. It is controlled by the
cylinder bolt in the bottom of the frame window locking into the bolt
notches on the cylinder OD. Thus, the indexing accuracy is determined by
the accuracy of the cylinder machining when it was made.

But the ratchet teeth need to move the cylinder to the proper
point so the "cylinder bolt" will drop into it. If the notch is not in
line, then the hammer will fall with the cylinder out of line. If it is
a *lot* out of line, the firing pin won't hit the primer, so there will
be no real problem (assuming that your life is not depending on the
thing firing when the trigger is pulled), but if it is just slightly out
of line, then the cartridge will fire, and it will (at best) spit a lot
of lead out one side or the other. With something as small as a .22,
and with as large a sensitive primer area (the whole rim), I could see
it being out of time by 1/2 the diameter of the bullet, which could be
quite nasty.

So -- make sure that when you are done, the locking lug
("cylinder bolt" above) falls cleanly into the index notch -- *before*
you ever put any ammunition in it.

Check what happens both with slow cocking and fast (as with
fast, it is likely that the momentum of the cylinder will spin it a bit
more, so the locking lug will drop in anyway as the notch tries to spin
past it).

And -- if it is double action -- see whether the behavior is the
same when it is driven by the trigger instead of the hammer (as wear in
the linkage between them could cause shifts in the timing, depending on
just how the indexing pawl is driven. Those that I have seen were
directly driven by the hammer, but a worn or sloppy bearing pin for the
hammer to rotate on could shift in different directions, depending on
whether the hammer is being pulled back by a thumb, or cammed back by a
trigger.)

So -- make sure that you know what it is going to do
mechanically *before* you let it fire live ammo.

Agree with all of the above. It can be a right fiddly PITA to do, too.
However, if you're only making one cylinder, or a couple, for the same
frame, here's what I did.

First, I cut the indexing star and made sure I had that right. Second,
I cut the locking bolt recesses and checked the cylinder locked up
tight. At this point I had a solid cylinder with indexing star and
locking bolts. I'd sorted end shake, headspace etc etc as well.

Then I made an accurate threaded barrel stub with reamed slip fit hole
on centre. Custom made centre punch to fit the bore. Remove barrel,
substitute barrel stub, bring cylinder to lockup, then use the punch to
mark the cylinder face. Ditto for all chambers. Worth doing it a couple
of times, not being too heavy handed, to check repeatability.

Now you *know* the centre of each chamber, at the important end - where
it lines up with the barrel. Pick up the centres, drill/bore/ream each
chamber. For a 22, using 4140, call it done.

Worked for me.

PDW
Greetings Peter and DoN,
I have decided to nix the extra cylinder. I feel that the smaller
pistol is too light weight for .22 mag and the other, top break pistol
may be too weak at the top for .22 mag. However, the smaller pistol
does need some work done on the cylinder system. As DoN suggested, the
indexing may be different faster or slower, trigger vs hammer. And
this is true. When using the trigger or hammer slowly it will index
perfectly. However, using the trigger fast will sometimes cause the
cylinder to index incorrectly. When this happens the trigger jams, as
does the cylinder. Fortunately, the hammer locks in a safety position
before the cylinder jams. So the hammer can't fall on the round. It
doesn't always jam. Just maybe one out of 40 or 50 trigger pulls. So
it's obvious that work needs to be done to this pistol. So, the first
thing to do is get the cylinder back in shape as mentioned in a
previous post. Then the indexing will be addressed. It looks like I'm
gonna be real familiar with this pistol when it's finished. Thanks for
the good advice.
Cheers,
Eric

On Tue, 13 Sep 2005 07:40:38 -0700, Eric R Snow
wrote:

. However, using the trigger fast will sometimes cause the
cylinder to index incorrectly. When this happens the trigger jams, as
does the cylinder. Fortunately, the hammer locks in a safety position
before the cylinder jams. So the hammer can't fall on the round. It
doesn't always jam. Just maybe one out of 40 or 50 trigger pulls. So
it's obvious that work needs to be done to this pistol. So, the first
thing to do is get the cylinder back in shape as mentioned in a
previous post. Then the indexing will be addressed. It looks like I'm
gonna be real familiar with this pistol when it's finished. Thanks for
the good advice.
Cheers,
Eric


One assumes that when you say...using the trigger fast, that you are
talking about a double action pull, IE pulling the trigger indexes the
cylinder, cocks and then drops the hammer after the bolt has locked
the cylinder in place?

You have a Timing problem in the works. Google Revolver Timing for
some good tips on fixing the issue

Gunner

"Pax Americana is a philosophy. Hardly an empire.
Making sure other people play nice and dont kill each other (and us)
off in job lots is hardly empire building, particularly when you give
them self determination under "play nice" rules.

Think of it as having your older brother knock the **** out of you
for torturing the cat." Gunner

DoN. Nichols wrote:
But the ratchet teeth need to move the cylinder to the proper
point so the "cylinder bolt" will drop into it. If the notch is not in
line, then the hammer will fall with the cylinder out of line. If it is
a *lot* out of line, the firing pin won't hit the primer, so there will
be no real problem (assuming that your life is not depending on the
thing firing when the trigger is pulled), but if it is just slightly out
of line, then the cartridge will fire, and it will (at best) spit a lot
of lead out one side or the other. With something as small as a .22,
and with as large a sensitive primer area (the whole rim), I could see
it being out of time by 1/2 the diameter of the bullet, which could be
quite nasty.

Most I've seen have the firing pin at 12 O'clock or 6 o'clock. I would
think very little rotation would move the pin off the edge of the case.