Cylinder endshake in the Dan Wesson

[unspellable]

What is normal cylinder endshake in a Dan Wesson?

If excessive, what's the fix?

How do you remove the ejector rod?

How do you remove the cylinder form the crane?

[cntryboy1289]

I stretch the gas ring to remove endshake by using a piece of wire and a vise.  Clamp the gas ring and a piece of wire in the groove and tighten the vise and turn it, repeat until the ring is strectched all the way around.  Then retry the cylinder again.

[unspellable]

I'm not quite sure I follow your method.  I'll have to drag out the exploded drawing and look at it I guess.

But before we get to cures, what's the proper amount of endshake?  One of the reasons for this question is that the ball and detent at the extractor applies a fairly stiff spring pressure to push the cylinder forward to the limit of its travel.  Since this would seem to eliminate the cylinder's forward run at firing, reduce the bounce back, and cushion the rearward run if any, I am wondering if the proper amount of endshake might be quite different than in a S&W.  maybe a better term is end play, since the spring tension eliminates "shake".  Also the gas ring collar limiting forward travel has a much larger bearing surface than the yoke tail in a S&W.

I've never heard of a DW shooting loose.  Mine don't have that much mileage on them anyway.  Any end play came that way from the factory.  (To tell the truth, I have a lot more endplay in my S&W's and Rugers that came from the factory than ever came from shooting.)

[gunnut69]

Because of DW's adjustable barrel/cylinder gap I think shims would be a better option. Ideally there should be no end shake, with the B/CylGap set properly. That is movement of the cylinder after lockup. The spring pushing forward on the cylinder will not stop the damage endshake causes.. The cylinder will be slowed a bit but the more endshake the faster you will get even more. There should be no more than needed for clearance at the rear of the cylinder. At least you won't have to worry about the B/C gap after it's tightened..

[unspellable]

I am not quite ready to discount the action of the spring.  The initial movement of the cylinder on firing is in the forward direction.  If the spring has it firmly forward to start with it cannot get a run.  It then would not bounce back either.  This thing may just be working on different principles than a S&W.

I was surprised to see that a Colt cap & ball has nothing at all to limit forward movement of the cylinder, but being a cap and ball the cylinder will blow backward on ignition of the powder charge rather than forward.

[unspellable]

If I had a shim, it would go in front of the gas collar?

Where would I get a shim?  A S&W, Ruger, or Colt shim might fit?

[gunnut69]

The shim is used to force the cylinder back limiting fore and aft movement of the cylinder. I don't know the caliber you have but doubt the spring can exert more force than the recoil of the round. When a cartridge fires the cylinder moves to the rear, to the limit of it's ability. The further it moves the more time it has to accelerate, the faster it'll wear. Shims can be bought from brownells or made by the gunsmith. The hammer blow will move any cylinder forward and the firing cartridge will move the vylinder to the rear.  This also adds to the barel/cylinder gap. There has to be enough tolerance for the action to function but as little as possible. Remember to measure with dummy cartridges in the cylinder. The recoil shield, case head clearance must be there to avoid locking up the gun on firing..

[cntryboy1289]

endshake should be no more than .002" on it.

[unspellable]

The cylinder is blown FORWARD on firing, not to the rear.  Any rearward movemnt is produced by bounce back after going forward.  Same principle as a blow forward action pistol.  In a S&W it's the yoke tail and bottom of the cylinder well that get beaten down, not the ratchet or frame.  That's also where the shim goes and why some people feel the revolver will hold up better with a shim because a good shim is well hardened.  The yoke tail is also the area that S&W heat treats in the endurance package.

On a cap & ball revolver the cylinder is closed at the rear and is blown back on firing.  A Colt cap & ball doesn't even have a limit to forward cylinder travel.  Remove the barrel and the cylinder will fall of the frame.

[gunnut69]

Motion of the cylkinder follows the energy release. The first energy relerase is the hammer strike against the primter and the cylinder moves forward. As the primer fires and pressure builds the bullet begins it's movement. For every action there's an equal and opposite reaction. So the cylinder moves to the rear. Its energy is transmitted to the frame at the recoil shield. The cylinder will bounce forward as the drops and the bullet exits the barrel. Then it's momentum being less thab the frame's will dissipate faster allowing it to slow a faster rate. The resulting inequality of velocities causes the cylinder to slam forward into the yoke.. The energy of the bullets acceleration is what forces the cylinder rearward. After the pressure drops the differentiation in mass will allow the cylinder to slow quicker causing it to slam forward as the recoil velocity of the frame is maintained at a higher level.  The greater the distance the cylinder has to  move back AND farward the faster this distance will grow. This is endshake. It must be control. In a S&W it is controled in several ways but the diffinculty is re-gapping the barrel after the endshake is removed. The DW doesn't have that problem. S&W realizing the advantages of this system used something similar in the new X-frames. The forward motion of a Colt C&B revolver is controled by the barrel/loading lever assembly and the wedge that retains it.

[unspellable]

On a cap and ball revolver the cylinder, being closed at the rear will on firing recoil to towards the rear.  It is simply a gun with in the gun.  In the case of a Colt, the wedge and ram have nothing what so ever to do with holding the cylinder back.  The cylinder is quite free to move forward and the only thing limiting forward travel is when it hits the barrel breech.  It would have to travel another eight of an inch to be limited by the front half of the frame.  The cylinder has no neck as does for example, the cylinder in a Blackhawk.

In a cartridge revolver the cylinder is blown FORWARD on firing.  Same principle as a blow forward action pistol.  When the primer detonates, it moves to the rear, out of the case.  When the powder burns it pushes the case to the rear, reseating the primer.  The case is limited in rearward travel by the recoil shield.  The cylinder is blown forward by the drag of the bullet on the throat walls.  The gas pressure is at right angles to the chamber walls and produces no significant force on the cylinder in either the forward or rearward direction.  In fact, a quick anaysis of the forces involved will show there is no significant force to move the cylinder to the rear other than bounce back after it hits the forward limit.

Check out a blow forward action pistol.  Its breech is stationary while the barrel is blown FORWARD.  This is an action type that never became very popular and is now obsolete, but it worked well enough.

Another example is the problem with setback in revolvers using bottle necked cartridges.  The case is limited in rearward travle by the recoil shield.  The cylinder is pushed forward and case expansion may prevent it from moving back again far enough to free up the cylinder.

You will note that in a S&W all the wear from end shake occurs at the interface between the yoke tail and the cylinder well bottom which limits FORWARD travel.  Very little wear occurs at the the ratchet which limits rearward travel.  When a ratchet does wear, it's due to the hand against the pawls which has nothing to do with firing stresses.

[gunnut69]

The case in a revolver seals to the shamber walls. This creates in effect a cylinder with the rear completely closed. The primer does extrude from its firing but the hammer or striker exerts enough pressure to retain it to a degree. If it were otherwise the primer would crater and have the raised rim distinctive to that condition. A cylinder IS sealed. It does not blow forward. The force of the hammer strike forces the cylinder forward, the pressure of the burning powder seals the case to the wall of the chamber. Where might the blow forward thrust come from?? The bottle necked Jet cartridge that S&W chambered in the M53 worked pretty well as long as the chambers were kept scrupulously clean. Any slippage would cause the case to extrude and lock up the revolver. If a revolver cylinder acted as a blow forward the case protruding from the rear of the cylinder and sealed to the walls of the chamber would lock up the gun every time.  The reason blow forward autoloaders and they were all autoloaders didn't fair well was the feed problem. It requires a mag that is designed to release the round in a rearward motion as opposed to the forward motion of common autoloaders. This makes putting the magazine in the grip frame quite difficult. The GyroJet Rocket pistol also had some magazine problems although that wasn't what killed it. A case blowing the chamber forward would act like a piston in an internal combustion engine, except it would not be forced back into the chamber. Instead it would lock up the cylinders rotation. A case under pressure is not free to slide in a chamber. If the prssure is great enough it will actually stretch. This is unusual in revolvers but in rifles it is the usual cause of case head seperations. As to gass pressure, note please the gas pressure in a cartridge is equal in ALL directions. It is simple physics. The gas will seek the least resistance and that is usually the bullet. Newtonian physics says that the motion inparted to the bullet by the powder gases and contained by the case sealed to the chamber walls, is applied to the containment structure. In this instance the cylinder.. The cylinder is the first part of the gun to recoil. The same facts are the reason the Browning A5 shotgun works. The entire bolt/barrels assembly is blown to the rear by the recoil caused by the accelerating shot charge.. If brass cases weren't formed to chamber dimensions by the pressures of firing, we wouldn't need sizing dies!

[unspellable]

When fired, the primer is pushed out of the case and conversely the case is pushed forward to the limit allowed by the head space.  The hammer does not restrain it.  There is a simple experiment you can perform here.  Simply load a primer in a case and fire the empty case with primer in a revolver.  The primer will back out, quite possibly tying up the revolver.  For this reason, cases for blanks and primer fired wax or plastic bullets have enlarged flash holes.  Back at the dawn of time there were pistol designs which used the force of the primer blowing back to actuate the pistol mechanism.  In a normal load the primer is reseated when the powder ignites and the case is pushed to the rear.  Note that the case DID NOT stick to the chamber walls.

In a blow back action, the case and breach block are blown to the rear.  This action would not work if the case stuck to the chamber walls.  Over the course of time, various attempts have been made to corrugate the chamber walls, etc. in an attempt to get the case to stick and retard the blow back.  They have met with VERY limited success.  It’s quite obvious that if the case were to stick to the chamber walls a blow forward action would not work.  The force tending to push the barrel or cylinder forward is due to the bullet drag on the walls.  In the blow forward action the case is free enough to allow the blow forward force to overcome not only the inertia of the barrel but the force of the return spring.

A gas in a container can exert a force on the walls only in a direction normal to the wall at any given point.  Hence the pressure tends to cause the chamber to expand, but it cannot produce any significant force tending to push the chamber either to the front or to the rear with a straight case such as the typical revolver case.

As for action and reaction, we are dealing with three components here, not two, the bullet is pushed forward, the case and recoil shield are pushed back, and the third component, the cylinder, is dragged forward with the bullet.  Any physical system can be modeled in any of several equally valid ways.  Some ways make a given point more obvious than others.  If instead of action/reaction, you examine the pressure induced force balance, you will find a force in all directions at right angles to the axis on the chamber walls.  The forces in this class sum to zero, producing no net movement.  The force on the base of the case is balanced by the force on the base of the bullet so they tend to move in opposite directions.  The drag of the bullet on the chamber/throat walls is the only unbalanced force acting on the cylinder so it tends to move forward.

Finally, all  this should be made obvious by the fact that in S&W’s we are forever stretching yokes or adding shims to compensate for wear at the yoke tail and cylinder well bottom which limits forward travel, but almost never replacing the ratchet which limits rearward travel.  We rarely have problems with headspace.  (I am excepting ratchets replaced because of pawl wear which occurs during rotation of the cylinder and has nothing to do with the discussion here.)

The revolver does not normally tie up because the case is springy and after firing the case contracts and is free to move within the chamber.

It’s true the 22 Jet would work well enough if kept religiously clean.  Other bottle necked cartridges in revolvers have done better as the 22 Jet case has a shape designed to provoke set back problems.  But the point is not howwell it did or didn’t work, but that the problem was one of shoving the cylinder forward and not allowing it to fall back thus tying up the revolver.

In the case of a recoil operated arm, the entire breech block, chamber, and barrel assembly recoil as a locked unit until the unlocking operation occurs.


All this said and done, we still don’t know what the correct end play clearance is for a DW revolver.

[gunnut69]

Pressure is not directional, It is applied withing a vesel equally to all surfaces at any tangent although resistance is directional. Perhaps the case/cylinder in its entirety moving rearward is what seats the bullet.  If the case cannot grip the chamber walls sufficiently to cause the cylinder to move rearward how would the bullet provide the force to accelerate the cylinder forward? The only reason the primer is forced from its chamber is the time line. The pressure builds in the primer cup prior to the powder charge igniting. The cylinder's inertia has not yet been overcome. If keeping the chamber walls oil free allowed the Jet to work, implying that it didn't work when the chamber was lubed, why? In your world the cases grip on the cylinder can't overcome any cylionder motion. Could it be that the slipage of the case on the chamber walls allowed it to force itself from the chamber and against the rcoil shield, tying up the piece. How amazing is it that a bullet reacting to the same prssures and having a fraction of the bearing surface of the case can effect the movment of a cylinder while the case, in the same pressure environment and having many times the bearing surface of the bullet has no effect on the chamber. I suggest you rethink your position.  If the case had no frip on the chamber walls the Jet would never have worked! If the Jet worked at all it was because it did grip the chamber walls and seal the cylinder.  All cases stick to the chamber walls. HK rifles have fluting in the chamber to reduce the cases grip on the chamber walls to allow this retarded blowback action to cycle without tearng off caseheads.  Blowback actions function because the action is held closed long enough by the mass of the reciprocating mechism, spring tension, and case adhesion to the chamber walls for prssure to drop to safe levels.

[unspellable]

The pressure of a fluid against a surface at any given point is normal to the surface at that point.  Basic statics 101.  There is NO force in any tangential direction.

That the case is sufficiently free to move to the rear is amply demonstrated by both the blow back and blow forward actions, both of which depend upon the case being free enough to slide in order to function.

The primer set back is related to the time line.  The primer compound is a high explosive, detonating and reaching its own peak pressure before the powder burn begins to build significant pressure.

Drive a case out the rear of a cylinder.  Then drive a bullet forward through the throat.  It will be obvious why the cylinder goes with the bullet.  (Unless you have an oversized throat.)

The case will initially be driven back.  If sticks to the cylinder, it will be with the cylinder forward, tying up the revolver.  This condition results because on firing both the case and the chamber expand.  When they spring back, the case must spring back to a size smaller than the chamber or you have a sticking case.

And finally, remember, we are quite used to dealing with wear at the point limiting forward travel of the cylinder, but it’s rare that we have to worry about such wear at the point limiting rear ward travel.  This is a telling point.  The end you beat on is the end you expect to get beat down.  (That said, I see a far more end play problems due to miss-fitted cylinders than due to wear.)

There is some friction between case and chamber.  In the traditional British pressure measuring method the cases are lightly oiled to reduce the error due to this effect.  The method actually measures back thrust rather than pressure.  The pressure is then derived from the measured back thrust.

The 22 Jet is an interesting problem that probably deserves more study.  Other bottle necked revolver cases do not seem to have had nearly the problem with set back that the 22 Jet did.  The obvious difference is the rather peculiar long tapered shoulder on the 22 Jet.  But when it ties up, it does so because the case does not spring back sufficiently.  The long tapered shoulder was probably an attempt to gain some grip on the walls, but its inspiration cartridge, the 22 Harvey K Chuck did not have the problem and it had a normal case with straight walls and normal shoulder.  I shoot the 17 HMR and the 357-44 B&D in revolvers and have never had either tie up due to back out.  So the 22 jet is an odd problem for which the correct answer mains to be found.

This still leaves the original question, what is the correct end play on a Dan Wesson?

[gunnut69]

Perhaps sir you should read and pay attention to the replies. cntryboy1289 supplied the answer to that question in his previuos reply. Blow forward and blow back actions actually function the same, they operate with low pressure rounds and relie on time selay and spring tension to hold the action shut until pressure has dropped enough to be safe. Oh wait,,, I already said that and you missed that also,, I believe sir that you miss a lot..

[RugerNo3]

The barrel to cylinder gap was already posted at .002". This all was overrun by a lot of unneccessary drivel and theory. The Freedom Arms 454 Casull is at.001-.0015" and that can get quite stiff from carbon build up. New S&W and Ruger ad infinitum production guns run at .005" nominal for a good compromise and function. A little noisy and less velocity, but what good is a locked up revolver from dirt and oily crust after a few days in the holster. Think about it as a function thing and not a wear thing. The nice feature on the Dan Wesson is this gap can be adjusted by setting the barrel back from time to time. My Ruger single actions have tight base pins and that is more important to wear and function then cylinder gap. Get it---.002" is a good compromise for function. An automotive feeler gauge can get this fit providing the barrel breech and cylinder are clean from carbon and or lead fouling. :roll:  

[gunnut69]

RugerNo3-- perhaps you'd better read a bit of that un necessary drivel. We weren't discussing barrel/cylinder gap and that is not what unspellable asked about. We were talking about endshake. That's the amount of front and back motion of the cylinder on it's rotational axis. Barrel cylinder gap is the distance between the rear of the barrel and the front of the cylinder. One should always know the question before answering it. Might I suggest you more closely read dome of the drivel, some cogent arguments were made and obviously you didn't understand them.

[killdeer]

Personally, I found that "UNNECESSARY DRIVEL"  entertaining as well as informative.