Need advise with a S&W 629 hammer

Doyle · June 19, 2009, 01:56 PM

I just picked up a used 629. The trigger pull appears to have been lightened as the DA pull is nice and sweet and the SA pull is almost scarry light. Those are OK. What worries me though is the hammer pullback. When I thumb the hammer back, the first half of hammer travel is extremely light. Then, it's like a 2nd spring kicks in and the last half of the pullback is much more difficult. I've never before seen another hammer feel the same way.

Any ideas?

Scorch · June 19, 2009, 02:07 PM

Sounds like someone has tried to do a trigger job by cutting a coil or two off of the rebound slide spring. I would recommend you take the pistol to a good smith or send it to S&W for service/repair.

Doyle · June 19, 2009, 03:08 PM

Scorch,looking at the schematic I can see how that might make the hammer pull lighter (as in the first half of the hammer travel). But, how would that make the 2nd half harder than normal?

If it really is the rebound slide spring, how hard is it to get to? I'm getting to be a fair garage gunsmith for simple jobs and Numrich has the replacement spring for less than $2.00.

Scorch · June 19, 2009, 05:24 PM

If you nip off a couple of coils, the trigger pull is reduced because the force of the spring against the trigger is reduced, and you will really feel it when the mainspring starts to flex then the rebound spring starts to get compressed. Check the strain screw on the mainspring also to make sure it is tight. If you really want to get into the guts of the pistol, open it up and take everything out, measure the length of the rebound spring and compare it to what S&W says it should be. While you have it open, you can check all the internal surfaces for burrs and varnished oil. Many times, just giving it a bath and oiling the works will smooth out the trigger.

LHB1 · June 19, 2009, 06:42 PM

The stacking/increasing resistance when cocking the hammer manually sounds to me like someone has severely bent and reshaped the orginal hammer spring. Try replacing this leaf spring with a Wolff reduced power hammer spring from Brownells and see if the problem goes away. I use this Wolff spring in all my K/L/N frame Smiths and it is great. It has slightly less strength than factory S&W hammer spring but I have not had any failures to fire in at least 8 different S&W revolvers over the last 20 years. ALWAYS keep the hammer spring tension screw in front of grip TIGHT.

To increase the trigger pull, simply replace the (probably shortened) rebound spring with one of the springs from Wolff reduced power hammer spring pack.

dahermit · June 19, 2009, 06:54 PM

Quote:

If you really want to get into the guts of the pistol, open it up and take everything out, measure the length of the rebound spring and compare it to what S&W says it should be.

If the rebound spring has not been cut, the ends of the spring will have a "finish" configuration on both ends. It it has been cut, it will be obvious upon inspection.
The length of lighter after-market reduced weight springs are all the same length despite having different pull weights.
In any case, measuring the length of rebound spring will not provide any useful information.

Dfariswheel · June 19, 2009, 06:58 PM

It's possible you're feeling "knuckling" of the mainspring.

If the strain screw is backed out or shortened too much, the mainspring can sort of kink, or "knuckle" during cocking.

My first move would be to check the strain screw to be sure it's screwed in all the way, and to see if it looks like it's been shortened.

Doyle · June 19, 2009, 06:59 PM

Please take a look at this Midway video. It looks like the spring kit from Wolfs is an easy change out. http://www.youtube.com/watch?v=5YWDK3OS7IA

I might order one (only $15.00) and put it in. Even if it doesn't solve the issue, I'll only be out small change.

**James K** · June 19, 2009, 07:55 PM

What has probably happened is that someone either screwed out the mainspring strain screw too far, or ground it off on the inside to reduce mainspring (hammer spring) tension. When you do that, the spring is too straight and when the hammer comes back part way, it comes up against the top of the mainspring, resulting in very hard cocking from that point on.

This is an indication of a "trigger job" done by an ignoramus, and likely a sign of more trouble to come. If you are lucky, you might get by with a new strain screw, but I bet you are looking at a new hammer and probably new trigger down the road.

Jim

Doyle · June 20, 2009, 11:44 AM

Problem solved. Jim's response made me take a look under the hood and sure enough, some cork soaker had backed the main spring strain screw all the way out. I'm going to shoot it like it is for a while and see if it is smooth enough for me. If not, I'll invest in a $15 spring kit from Wolf and see what that does.

Thanks for all your help guys. This is my first S&W. I have previously been a Ruger man. The Smiths are a lot more complex.

June 19, 2009, 01:56 PM	#1
Doyle Senior Member Join Date: June 20, 2007 Location: Bradenton, Fl Posts: 4,158	Need advise with a S&W 629 hammer I just picked up a used 629. The trigger pull appears to have been lightened as the DA pull is nice and sweet and the SA pull is almost scarry light. Those are OK. What worries me though is the hammer pullback. When I thumb the hammer back, the first half of hammer travel is extremely light. Then, it's like a 2nd spring kicks in and the last half of the pullback is much more difficult. I've never before seen another hammer feel the same way. Any ideas?

June 19, 2009, 02:07 PM	#2
Scorch Senior Member Join Date: February 13, 2006 Location: Washington state Posts: 11,113	Sounds like someone has tried to do a trigger job by cutting a coil or two off of the rebound slide spring. I would recommend you take the pistol to a good smith or send it to S&W for service/repair. __________________ Never try to educate someone who resists knowledge at all costs. But what do I know? Summit Arms Services Taylor Machine

June 19, 2009, 05:24 PM	#4
Scorch Senior Member Join Date: February 13, 2006 Location: Washington state Posts: 11,113	If you nip off a couple of coils, the trigger pull is reduced because the force of the spring against the trigger is reduced, and you will really feel it when the mainspring starts to flex then the rebound spring starts to get compressed. Check the strain screw on the mainspring also to make sure it is tight. If you really want to get into the guts of the pistol, open it up and take everything out, measure the length of the rebound spring and compare it to what S&W says it should be. While you have it open, you can check all the internal surfaces for burrs and varnished oil. Many times, just giving it a bath and oiling the works will smooth out the trigger. __________________ Never try to educate someone who resists knowledge at all costs. But what do I know? Summit Arms Services Taylor Machine

June 19, 2009, 06:42 PM	#5
LHB1 Senior Member Join Date: March 25, 2005 Location: Houston, TX Posts: 1,545	The stacking/increasing resistance when cocking the hammer manually sounds to me like someone has severely bent and reshaped the orginal hammer spring. Try replacing this leaf spring with a Wolff reduced power hammer spring from Brownells and see if the problem goes away. I use this Wolff spring in all my K/L/N frame Smiths and it is great. It has slightly less strength than factory S&W hammer spring but I have not had any failures to fire in at least 8 different S&W revolvers over the last 20 years. ALWAYS keep the hammer spring tension screw in front of grip TIGHT. To increase the trigger pull, simply replace the (probably shortened) rebound spring with one of the springs from Wolff reduced power hammer spring pack. __________________ Good shooting and be safe. LB

June 19, 2009, 07:55 PM	#9
James K Staff Join Date: March 17, 1999 Posts: 16,611	What has probably happened is that someone either screwed out the mainspring strain screw too far, or ground it off on the inside to reduce mainspring (hammer spring) tension. When you do that, the spring is too straight and when the hammer comes back part way, it comes up against the top of the mainspring, resulting in very hard cocking from that point on. This is an indication of a "trigger job" done by an ignoramus, and likely a sign of more trouble to come. If you are lucky, you might get by with a new strain screw, but I bet you are looking at a new hammer and probably new trigger down the road. Jim __________________ Jim K

June 19, 2009, 03:08 PM	#3
Doyle Senior Member Join Date: June 20, 2007 Location: Bradenton, Fl Posts: 4,158	Scorch,looking at the schematic I can see how that might make the hammer pull lighter (as in the first half of the hammer travel). But, how would that make the 2nd half harder than normal? If it really is the rebound slide spring, how hard is it to get to? I'm getting to be a fair garage gunsmith for simple jobs and Numrich has the replacement spring for less than $2.00.

June 19, 2009, 06:58 PM	#7
Dfariswheel Senior Member Join Date: May 4, 2001 Posts: 6,589	It's possible you're feeling "knuckling" of the mainspring. If the strain screw is backed out or shortened too much, the mainspring can sort of kink, or "knuckle" during cocking. My first move would be to check the strain screw to be sure it's screwed in all the way, and to see if it looks like it's been shortened.

June 19, 2009, 06:59 PM	#8
Doyle Senior Member Join Date: June 20, 2007 Location: Bradenton, Fl Posts: 4,158	Please take a look at this Midway video. It looks like the spring kit from Wolfs is an easy change out. http://www.youtube.com/watch?v=5YWDK3OS7IA I might order one (only $15.00) and put it in. Even if it doesn't solve the issue, I'll only be out small change.

June 20, 2009, 11:44 AM	#10
Doyle Senior Member Join Date: June 20, 2007 Location: Bradenton, Fl Posts: 4,158	Problem solved. Jim's response made me take a look under the hood and sure enough, some cork soaker had backed the main spring strain screw all the way out. I'm going to shoot it like it is for a while and see if it is smooth enough for me. If not, I'll invest in a $15 spring kit from Wolf and see what that does. Thanks for all your help guys. This is my first S&W. I have previously been a Ruger man. The Smiths are a lot more complex.