Just completed my first action job.

[scooter123]

On my model 67-1, with the assistance of Jerry Kunhausen's manual. After opening it up, it bacame pretty obvious why the action in this gun was so slick, the DA sear had previously been chamfered and the rebound slide had also been stoned. So all I actually did was swap in a 12 lbs. rebound spring and button it back up. I did not swap in a lighter mainspring or file down the strain screw because I wanted the ignition cycle to be at full power.

Overall it was pretty simple but I am really pleased that I had the forthought to purchase Brownell's rebound slide tool. Trying to put that back together without this tool would have had me taking the gun into a local gunsmith for re-assembly. With the tool it's a bit fussy getting the spring compressed and past the pin, without that tool I cannot concieve of how it could be done without triggering a stroke.

Getting the sideplate back on was a bit of trial and error because getting that hammer block back into it's nest in the side plate is a bit tricky.

Function test was 100% perfect and the lighter rebound spring has probably reduced the DA pull by about 1/2 to 1 lbs. Not a lot but just about where I wanted it. I have also tested the function in rapid fire with the lighter rebound spring and the gun works perfectly as fast as I can pull the trigger. So, in hindsight I probably could have used the 11 lbs. rebound spring. Since I have 3 more to do, I'll probably try the 11 lbs. spring in my 610 since it's not really suitable for rapid fire drills, too much muzzle mass for me to shoot it really quickly.

Now a question for those who can provide some guidance. Jerry's book doesn't cover the guns with a frame mounted firing pin, which my 610 and 620 have. I purchased 0.015 inch extended firing pins from Cylinder and Slide for these guns and plan on putting them in when I go into the action. I know that it's a simple matter of removing the retaining pin and swapping out the firing pin, however I do not know how to remove that retaining pin. Is it a simple slip fit that will fall out with some light tapping on the frame or is something more involved? Some tips on this would be greatly appreciated. BTW, I have some pretty powerful small neodymium magnets at work that might have enough pull to remove the pin if it is a slip fit.

I would also appreciate any tips on the best position to hold the gun to easily get that hammer block to nest into the sideplate.

 

[hsguy]

On my model 67-1, with the assistance of Jerry Kunhausen's manual. After opening it up, it bacame pretty obvious why the action in this gun was so slick, the DA sear had previously been chamfered and the rebound slide had also been stoned. So all I actually did was swap in a 12 lbs. rebound spring and button it back up. I did not swap in a lighter mainspring or file down the strain screw because I wanted the ignition cycle to be at full power.

Overall it was pretty simple but I am really pleased that I had the forthought to purchase Brownell's rebound slide tool. Trying to put that back together without this tool would have had me taking the gun into a local gunsmith for re-assembly. With the tool it's a bit fussy getting the spring compressed and past the pin, without that tool I cannot concieve of how it could be done without triggering a stroke.

Getting the sideplate back on was a bit of trial and error because getting that hammer block back into it's nest in the side plate is a bit tricky.

Function test was 100% perfect and the lighter rebound spring has probably reduced the DA pull by about 1/2 to 1 lbs. Not a lot but just about where I wanted it. I have also tested the function in rapid fire with the lighter rebound spring and the gun works perfectly as fast as I can pull the trigger. So, in hindsight I probably could have used the 11 lbs. rebound spring. Since I have 3 more to do, I'll probably try the 11 lbs. spring in my 610 since it's not really suitable for rapid fire drills, too much muzzle mass for me to shoot it really quickly.

Now a question for those who can provide some guidance. Jerry's book doesn't cover the guns with a frame mounted firing pin, which my 610 and 620 have. I purchased 0.015 inch extended firing pins from Cylinder and Slide for these guns and plan on putting them in when I go into the action. I know that it's a simple matter of removing the retaining pin and swapping out the firing pin, however I do not know how to remove that retaining pin. Is it a simple slip fit that will fall out with some light tapping on the frame or is something more involved? Some tips on this would be greatly appreciated. BTW, I have some pretty powerful small neodymium magnets at work that might have enough pull to remove the pin if it is a slip fit.

I would also appreciate any tips on the best position to hold the gun to easily get that hammer block to nest into the sideplate.

The easiest way I have found to deal with the hammer block is to place it in the gun pushed all the way to the top of it's travel and then angle to top of the side plate so the block fits in the groove and slide the plate into position.

 

[haggis]

The FP retaining pin is a very loose fit.

Buck

 

[500 Magnum Nut]

On my model 67-1, with the assistance of Jerry Kunhausen's manual. After opening it up, it bacame pretty obvious why the action in this gun was so slick, the DA sear had previously been chamfered and the rebound slide had also been stoned. So all I actually did was swap in a 12 lbs. rebound spring and button it back up. I did not swap in a lighter mainspring or file down the strain screw because I wanted the ignition cycle to be at full power.

12 LB rebound, I bet you a coffee that full power main spring is either replaced or it's strain screw was shortened.

No way the trigger would reset otherwise.

Push up the block all the way, before placing the side plate back on. There is a picture in the FAQ.

 

[scooter123]

Magnum Nut, today I did the same to my 610-3, which was factory new before I opened it up and the trigger resets perfectly with a 12 lbs. rebound spring, even when I release the trigger in slow motion. When released very slowly there is one point where it starts to catch but it will move past that point with very little pressure on the finger and resets fully. Based on this, I now know that the 11 lbs. rebound spring would probably be a problem. I do know that you have a lot more experience than I do with these revolvers, but I can only report what I have found in using these springs on two of my revolvers.

BTW, I purchased the full rebound spring kit from Brownell's, so if any reset issues do come up I can always put in a heavier rebound spring. These are Wolff gunsprings purchased through Brownells, so the spring rate may not be quite as advertized. What I do know is the springs marked as 12 lbs. has a wire diameter of 0.029 inch while the factory spring has a 0.034 inch wire diameter. Length for the Wolff spring is also 0.05 inches longer than the factory spring from the 610. However, I just trimmed one of the 12 lbs. Wolff springs to match the factory length and just swapped it into the 610 and it still resets perfectly with the slightly shorter 12 lbs. marked spring.

Concerning the 67-1, the gun was purchased used and it obviously had some prior action work. After doing the 610 I found the rebound spring for the 67 had been cut back by 2 full coils by comparing it to the spring from the 610. The trigger on the 67 was always so slick that I suspected an action job and what I found just confirmed it. However, the gunsmith did miss on chamfering the corner on the rebound slide so I added that chamfer when I had it out of the gun.

I've also found that the weaker rebound spring reduces the trigger pull in single action by a bit. With the factory rebound spring in place I could pick up the 610 by the trigger with the gun cocked and the trigger would not release, now the trigger releases before the gun will lift off the floor. BTW, the 610 has a rail and older red dot mounted so it's about 55 ounces total weight. Best guess is the single action pull is now in the range of 2 1/2 to 3 lbs., which I am not totally comfortable with. I've always shot with a 3.5 to 4 lbs. SA trigger and the now lighter SA trigger in the 610 is going to take some getting used to. However, I'll see how it works at the range in single action before deciding it's just too light for me in single action.

I also found the sideplate on the 610 much easier to get back in place because S&W has opened up the channel for the hammer block. With the 610, all I had to do was slide the safety bar to the top postition as suggested, get the sideplate positioned, and push it down firmly with my thumb. Then it's just a matter of a couple of taps with a rubber handled screwdriver to seat it fully and putting the screws back in place.

BTW, I noticed on the 610 that the Flat Head sideplate screw was not used for the rearmost position. Both of the rear screws on my 610 were the Round Head sideplate screws. Don't know if that was a mistake on S&W's part or a change they have made because they are now shipping the guns with rubber grips and the round head screw standing proud of the surface isn't an issue with rubber grips. However, I am glad that I ordered some extra sideplate screws from Brownells, because I have some spare Flat Head that I can use if I decide to mount some wood grips on the 610.

As for swapping out the firing pin, holy smokes that was as easy as it could get. I really didn't need the extended firing pin because the 610 has been 100% reliable for ignition. However, it's only been shot using Federal 40 S&W from Walmart. This weekend I'll be hitting the range and I'll make sure to check for any evidence of pierced primers with the Federal ammunition. If it's an issue, I'll put the factory pin back in. I was thinking along the lines of trying a reduced power mainspring, which is why I purchased the extended pins. However, as much as a simple rebound spring change reduced the SA trigger pull, I may just let the gun remain as is. One thing I am not confident of is modifying the SA sear, so I intend to leave that as it left the factory on all of my revolvers.

Now, what is left is my 617 no dash and my 620. I'll be curious to see if the 620 uses the same screw set as what came on my 610.


Now a question. My 617 has the serated target trigger and I am starting to find that I like this trigger. Brownells only lists a serated trigger for the K frames and I am toying with the thought of putting a serated trigger in my 610. That way both of my long barreled full lug target guns would have matching hammers and triggers, a symetry I find appealing. Are the K and N frame triggers the same part or should I be posting a WTB request in the WTB forum?

PS, before anyone freaks out about my cavilier mention of function checks and lifting a cocked gun by the trigger, I ALWAYS ALWAYS make sure to load the cylinder with snap caps before doing any of this kind of testing. Safety for me is JOB one and I am a bit OCD about it, to the point where I will look 4 or 5 times to make sure that any gun I am working on is really really unloaded before I do any work on it. Mild OCD runs in the family and sometimes it's not a handicap, however people watching me working on something do get a bit impatient with my obsession for triple and quadruple checking.

 

[500 Magnum Nut]

Little differences, but the correct vintage should work and be a drop in. Swap the hand original to the gun with the replacement trigger.

 

[scooter123]

A quick followup on my installation of the 12 lbs. rebound spring in my 617 and 610. Turns out that just because it works fine in a function check, that doesn't mean it will work fine during live fire. On the 617 the 12 lbs. rebound spring caused zero issues in 100 rounds downrange. With the 610, it was another story, the trigger failed to reset twice in 48 rounds of live fire with the 40 S&W. It's either a matter of the recoil causing a slght bind, or just carrying the rebound slide with the frame due to inertia, but 500 Magnum Nut was CORRECT, 12 lbs. is too light for a gun using the factory mainspring. I've learned from this and my 610 and 67 are now equipped with a 14 lbs. rebound spring and I'll see if I have any reset issues on my next trip to the range. I'm going to leave the 12 lbs. spring in my 617 simply because I am curious to see if the lighter spring will present an issue at some point.

I also took a good look at the fired cases from the 610 because at the same time I did the rebound spring I put in an extended firing pin. Firing pin impression is very distinct but I did not see any hint of the primer being struck hard enough to cause a pierced primer. BTW, ammo used was Federal Champion 40 S&W.

Next up will be to make up some steel shims to place under the strain screw. It will take some time, but I plan on experimenting with 0.010, 0.020, & 0.030 shims under the strain screw and seeing what effect this has on the reliability and trigger pull.

BTW, this experiment noticeably reduced the trigger pull in Single Action, which was a bit of a concern since I haven't much experience with a SA trigger this light. Turned out that it wasn't as big of an issue as I thought it might be, did not have one single premature or inadvertant discharge, however I was paying attention to what I was doing with my trigger finger. While I wouldn't want a trigger this light in a SD situation, it turns out that in a range setting it wasn't a problem. All I had to do was pay attention, which I always do when handling any firearm. However, in comparing my bench shooting results with the 617 before/after the change in the rebound spring, I didn't seen any improvement in my grouping due to the lighter SA trigger.