Yoke side to side play on a M&P

[walnutred]

I have a M&P with good lock-up and little end play in the cylinder but the yoke seems loose. If I push laterally on the rear of the cylinder, no movement. However if I push laterally on the front of the cylinder or ejector rod there is play. The only thing that looks odd in the retaining pin in the barrel lug seems shorter than the ones in my other K frames. Could fixing this be as simple as replacing the locking plunger or are there other things I need to look at first?

Thanks

 

[john traveler]

Excessive yoke play can be caused by improper fit of the extractor rod to the forward locking lug, or by a slight misindex of the barrel. The side-to-side play of the extractor rod fit can be inspected by pushing on the crane with cylinder in locked position. If excessive, it can be the barrel is too loose by a few degrees.

 

[500 Magnum Nut]

The front lockup doesn't do much. That's why they put that ball on the yoke then under recoil the ball holds the yoke in place. You see this on some 357s from years ago or today on the X frame.

If the yoke barrel is under sized or worn, there is not much you can do but replace the yoke.

When the cylinder opens and closes does it do so without forcing it closed? It should close with a simple click as the center pin finds home. This will prove the yoke isn't sprung out of position.


Dryfire the gun & hold down the trigger. Now the gun is in lock up. In this position only is it critical how the chambers line up to the bore. If alignment is good (without pressing on anything to push it out of alignment) then your gun is safe to shoot.

But....


If you really want to check alignment then the tool I use for this are range rods. Range rods are finely made pins that slide down the barrel to gauge exactly where the bore is in relation to the chambers. The tool is used when the gun is in full lock up with the muzzle pointed upwards. Every chamber is inspected this way.

Only then you will prove the yoke is in proper alignment, the cylinder stop, hand & ratchets are all working together.

 

[walnutred]

Thanks for the pointers. Lock-up seems good when dry fired and the cylinder opens and closes smoothly. I have a spare front locking pin so maybe I'll replace that. However it shoots OK with no lead shaving so I may just not worry about it.