Greetings,
I am trying to track down a flat primer issue in my S&W 629-3. No matter how I reload I am getting flatened primers. Factory ammo, at least 180gr. doesn't flatten. It was suggested that it might be a head space issue, ie the distance between the head of the case and the frame. What should the head space measure, how is that measured?
Thanks.

stephen b

Headspace in the Smith & Wesson revolver is considered "go" with a clearance over shell head of .006, and "no-go" being .010, though some will argue .012.

Cylinder end shake is usually responsible for excess headspace in the S&W revolver and must be dealt with first when determining actual headspace. Here's how to check the headspace on your gun.

Insert a unprimed factory case in the chamber. push and hold the cylinder at it's most forward position and insert a feeler guage between the shell head and the recoil shield at the firing pin bushing. You should be able to insert a feeler guage of .006 -.009 to be considered safe. If a leaf of .010 or greater will fit then it is considered unsafe.

Try this and then repost your results.

Good luck,

Malm

Stephen,

I appologize, I addressed only part of your post. If you experience no problem with factory loads, then the problem may just lie with your handloads. How flat are your primers? What primers are you using?

Malm

Malm,
Thanks for your reply. I did as you have instructed and found that my head space was between .011 and .012 depending on the position of the cylinder (?). I checked the head shake and at full lockup it was .008.
I'm using Winchester large pistol primers, 240 Hornadys 240gr xtp\hp's and 23.2 gr w-296.
From what you have said it looks like my 629 might be going back to Springfield,MA.

stephen b

Stephen,

Now, re-measure with the cylinder held at it's rear most position. When addressing endshake in S&W's, the repair moves the cylinder back towards the recoil shield effectively closing the gap or headspace. There is also yoke endshake which exists at the point where the cylinder screw is located. This too needs to be taken into account when correcting any headspace/endshake trouble. Make this measurement and repost the results please.

23.2 grains of 296 powder and a 240 grain bullet is about a mid load for the 44 Mag. Were it me, I would try a different primer just to see what happens.

Malm

Malb,
The gap at the rear of the cylinder, pushed back, is .009. If the cylinder screw is that screw which retains the crane, the measurement between the cylinder and the frame, at the screw, is .012.
I will definately try different primers. I presume that the excessive play in the cylinder needs to be adressed as it seems to be a safety issue.

stephen b

Stephen,

.009 is fine. Now find someone who can stretch and finish the crane, or fit endshake bearings to reduce the gap and you will be good to go. The yoke screw was just mentioned because there can exist enough lateral play in this area, to add to the endshake problems.

Good luck,

Malm

Malm,
Thanks for your help. I'm glad that I was alerted to the problem before it got any worse. When purchased, the 629 looked virtually unused and was very tight. I've shot about 500 rounds through it and it has loosened up ever so slightly. I had not gapped the tolerences so I don't know what they were to begin with, but I will in the future.
I appreciate the imparted knowledge.

stephen b