Model 29 Endurance package question

[awp101]

Is the Endurance package developed for the Model 29 an update that can be retrofitted to older models that didn't get it (like the "M" mods for the original L Frames) or are the changes substantial and go beyond just a simple parts swap?

Thanks!

[mike454]

i don't believe that the whole endurance package could be added to an existing gun. I thought to add the bolt block, some changes were made to the frame, could be wrong on this. Also the cylinder bolt notch dimentions were changed, perhaps the bolt as well. the yoke and perhaps some other related parts were hardened and the internal studs were changed to a radiused design.

[awp101]

Thanks, that's what I was thinking but didn't know for sure. I didn't know if it was something S&W would/could do if a pre-29-4(?) went back to the Mothership or if it had to leave the factory that way.

[bradshaw]

Oct 31, 2017 6:53:05 GMT -5 mike454 said:

i don't believe that the whole endurance package could be added to an existing gun. I thought to add the bolt block, some changes were made to the frame, could be wrong on this. Also the cylinder bolt notch dimentions were changed, perhaps the bolt as well. the yoke and perhaps some other related parts were hardened and the internal studs were changed to a radiused design.

*****

S&W’s answer to "CYLINDER FLOAT" was to elongate the STOP NOTCH. The S&W STOP (a.k.a. cylinder stop; Colt calls it a bolt), oscillates on a post in the frame. Oscillation----fore and aft movement----enables the stop to reset after the trigger disengages it from the cylinder. As for a "bolt block,” the traditional S&W stop is drop forged with a built in “block” to prevent side movement in the retracted position. Otherwise, the stop could get hung up during trigger or hammer cocking. Owing to the forward-aft movement of the stop and its cramped space in the frame, the S&W stop spring is weak, much weaker than, say, the stop spring on a Ruger double action Security-Six, GP-100, Redhawk, etc.

A cylinder stop or bolt is held in the raised position by a spring and rotates vertically. There is no mechanical lever to hold the stop against the cylinder, just a spring. Inertia of a stop acts to hold it in place as a big bore revolver rises on recoil. This inertia can cause the cylinder to unlock. At the same time, the hammer can bounce from steel-on-steel contact with the frame.

“... internal studs... changed to a radiused design.” Not sure what this means. Does it refer to posts in the frame on which the hammer and trigger rotate? If so, the posts have for generations been domed to ease placement of the SIDEPLATE. While the elongated----“enhanced”----notch helps keep the stop from bouncing out on recoil, it does nothing to increase cylinder strength.

The hammer and trigger post, along with the yoke pivot, have been known to work loose on improperly made Model 29s. I refer to the Bangor-Punta era, when quality veered from superb to lousy. I have seen the yoke pivot pop out on a new M-29 before it has fired a box. Trigger and hammer posts coming unswaged. All the while, a properly made M-29 holds up with ZERO failures of any kind through many thousands of rounds of silhouette and hunting ammunition. Oh, expect maintenance of continuous use: the barrel must be set back to correct BARREL FACE erosion, the cylinder pin will peen and need replacement, or a touch of file work, the stop may wear out, yet with maintenance & lube these revolvers never experience a failure to cock, lock-up, or fire. This all takes place just below max load levels. Softening pressure just enough to award the revolver a degree of immortality. Power enough for a steel ram or the wiley whitetail.
David Bradshaw

[kooz]

I have a 629-1 that I sent back to have the cyl replaced and an action job . I asked if I could have the endurance enhancements done that could be done while there , they said no problem . They obviously can't do them all , but what could be fitted to the gun they accomplished .

[awp101]

Thanks for the info Mr B and kooz. I'm slowly warming to the idea of picking up a Model 29 so I'm trying to do my due diligence ahead of time. Most likely anything I get would never need the package since it would only see .44 Special and occasional light Mag loads.

[mike454]

Nov 2, 2017 8:07:51 GMT -5 bradshaw said:

Oct 31, 2017 6:53:05 GMT -5 mike454 said:

i don't believe that the whole endurance package could be added to an existing gun. I thought to add the bolt block, some changes were made to the frame, could be wrong on this. Also the cylinder bolt notch dimentions were changed, perhaps the bolt as well. the yoke and perhaps some other related parts were hardened and the internal studs were changed to a radiused design.

*****


“... internal studs... changed to a radiused design.” Not sure what this means. Does it refer to posts in the frame on which the hammer and trigger rotate? If so, the posts have for generations been domed to ease placement of the SIDEPLATE. While the elongated----“enhanced”----notch helps keep the stop from bouncing out on recoil, it does nothing to increase cylinder strength.

The hammer and trigger pivots were radiused where they join the frame to help prevent shearing

[bradshaw]

mike454.... which radius at the base of the pin----with corresponding chamfer on hammer & trigger----tells us these guns have a stress factor unknown to earlier S&Ws, which do not suffer broken pins.
David Bradshaw