Jump to content
Brian Enos's Forums... Maku mozo!
Justin M

Trigger Job Question

Recommended Posts

I have developed what I believe is a fairly straight-forward method to get to a 4lb trigger on a N-Frame S&W.  I'm a pragmatic guy who relishes in routine.  I used a 4" 627 to develop my method so as not to screw up any of my "race" guns.  Once I had the process, I applied it to a couple of 929s and 627/327s.  No issues at all.  I suspect this is very similar to how everyone else does it - no new or novel approach here.  All parts get stoned and/or hit with the Foredom (big Dremel, sometimes it's a Dremel - if that's closer on the bench), an 11lb rebound spring cut down between 1-2 coils, a Wilson mainspring bent to my particular pattern (I've snapped two S&W mainsprings, so I refuse to use them any longer), a X Frame cylinder stop spring, a Cylinder & Slide firing pin (against all recommendations), a snipped firing pin spring, and a 175-200gr "Carmonized" hammer.  All guns, so far, are reliable with Federal 100s - plus or minus a couple ounces of 4lbs.  I usually end up moving the pull weight up to between 5 and 6lbs because I happen, for whatever reason, to shoot better points with a slightly heavier trigger.  

 

So, buddy asked me to "Carmonize" his hammer and get his new (to him) 929 ready for USPSA.  He wants to use Winchester primers, because, um... not sure, but that's his thing, right?  I go about my routine to get to a 4lb trigger figuring I'll get it set up at 4lbs, make sure it's reliable with Federal 100s, then up the mainspring until it reliably fires Winchester primers, and balance out the rebound spring. Gun refuses to reliably fire Federal 100s at 4, 5, 6, ... all the way up to about 10lb.  It'll fire some, but not all.  It'll fire some, but not all Winchester primers at the heavier settings as well.  Of course, match in the morning, because that's how this usually goes, right?!.  I take out my beautiful, super-light "Carmonized" hammer and throw in an Apex hammer and it starts to work, but still at the heavier settings.  Maybe 8lbs give or take.  

 

I'm having hime come back this afternoon to try out an Apex pointy firing pin and to check headspace.  I cannot figure out what else it might be.

 

My questions: 

 

1.  On the Apex pointy pin, why pointed?  All things being equal, will that pin give more reliable ignition than a stock or a similar (rounded or blunt nose) firing pin?  

 

2. What else could be going on here?  There's no drag on the "Carmonized" hammer, the Apex hammer, the firing pin, etc.  Hammer block is laying on bench.  Not more than .002" end shake. Not sure where to look.

 

3.  Unrelated, I think, but still might inform some of this: Why does the Apex .22 hammer have more mass?  If lighter is better for hammers, why does this change from rimfire?

 

Share this post


Link to post
Share on other sites

Have you checked to make sure the hammer isn't cracked?

Some have had cracked hammers when too much is taken off or if there might be a weak spot in the metal you weren't expecting.  Hair line cracks can be hard to see also.

Also did it work reliably stock?

Way outside the norm issue, does the fp hole match where the primer is?  Would seem really obvious but weird things do happen.

 

Keep us informed.

 

Apex did an action job at 4 lbs for me on a 625PC.  I never could get used to it, the sweet spot for me is also 5-6 lbs.

At 4 lbs my mind kept telling my finger I was shooting a 1911 and I would fail to release the trigger enough. I know after a few thousand rounds I'd get used to it, but at that weight it just doesn't take much to cause a ftf.  Upping a pound and a half seemed to be a bit of insurance also.

Share this post


Link to post
Share on other sites

1. Don't know about pointed, ask Apex.

 

2. It sounds like the hammer is hitting something in the action that absorbs some of the striking force. The main 2 things I can think of right off are the hammer block and the rebound slide. The hammer block may not be getting all the way down. You can check that by removing it and test firing to see if the problem goes away. The rebound slide may not be getting all the way back, especially if there's a trigger stop. Then the bottom of the hammer could hit the rebound slide just before the top hits the firing pin. You can check that by pulling the trigger, then hold the top of the hammer all the way down on the frame. Then move the trigger front to back and see if there is some free play where the rebound slide is going back behind the hammer.

 

3. The .22 hammer has to be heavier because the rim of the .22 case is harder to dent than a centerfire primer. The primer has one thickness of metal with support far away from where the firing pin hits. The rimfire is 2 thicknesses of metal with a 180 degree bend where the firing pin hits. The bent area lends a good bit of support right where the dent goes.

Share this post


Link to post
Share on other sites
5 hours ago, Justin M said:

big Dremel, sometimes it's a Dremel 

 

 

 

No.

Share this post


Link to post
Share on other sites
11 minutes ago, alecmc said:

No.

 

I'm not sure I should reply, but I feel I must (and it beats working)... What is that "no" for?  Are you disagreeing that a Foredom is just a big Dremel? 

 

I will be checking out the 929 this afternoon, I hope, to see what I can come up with.  

 

So far, this is what I know:

 

1.  Hammer is not cracked.  I inspected it as best as I could.  Put it under magnification, tested it another gun (627), and - short of magna fluxing it - I believe it to be sound.  

 

2. The hammer was free to move when I installed it.  I checked this several times when the problem first came up.

 

3.  I will check firing pin hole location when I get the gun back.

 

4. I will be checking headspace as well.  This was an issue with my first revolver, a TRR8.

Share this post


Link to post
Share on other sites
Posted (edited)
35 minutes ago, Justin M said:

 

I'm not sure I should reply, but I feel I must (and it beats working)... What is that "no" for?  Are you disagreeing that a Foredom is just a big Dremel? 

 

I will be checking out the 929 this afternoon, I hope, to see what I can come up with.  

 

So far, this is what I know:

 

1.  Hammer is not cracked.  I inspected it as best as I could.  Put it under magnification, tested it another gun (627), and - short of magna fluxing it - I believe it to be sound.  

 

2. The hammer was free to move when I installed it.  I checked this several times when the problem first came up.

 

3.  I will check firing pin hole location when I get the gun back.

 

4. I will be checking headspace as well.  This was an issue with my first revolver, a TRR8.

 

 

I disagree that a dremel belongs anywhere near a revolver trigger job. -- It has its place in bobbing hammers and chamfering cylinders - but " buffing " parts - Nope.

 

And I can only say because i've been there and done that, and had some extremely knowledgeable and reputable mentors properly educate me.

 

Also, In my opinion - there is a difference between making a trigger light, and actually making a trigger smooth. Making a trigger light is easy - a few springs and some federal primers and you have a light trigger. But a smooth responsive trigger is something that takes alot of work. 

 

Again, just my personal opinion - Do whatever works for you and gives you the results you want - more than one way to skin a cat. 

 

As far as your issue - Make sure that the timing is spot on - If your primer strikes are off center they can also cause light strikes. 

 

Also , check to make sure that the hammer is making it's full stroke back, double check to make sure the hammer is actually transitioning off the double action sear , to the double action cam on the hammer , and falling off from there. If you removed too much material from one surface or another it may be falling early and not having it's full potential momentum to light off the primers.

 

 

Best of luck,

Alec

Edited by alecmc

Share this post


Link to post
Share on other sites
Posted (edited)
37 minutes ago, alecmc said:

I disagree that a dremel belongs anywhere near a revolver trigger job. -- It has its place in bobbing hammers and chamfering cylinders - but " buffing " parts - Nope.

 

We agree. 

 

37 minutes ago, alecmc said:

Also, In my opinion - there is a difference between making a trigger light, and actually making a trigger smooth. Making a trigger light is easy - a few springs and some federal primers and you have a light trigger. But a smooth responsive trigger is something that takes alot of work. 

 

We are still in agreement.

 

37 minutes ago, alecmc said:

As far as your issue - Make sure that the timing is spot on - If your primer strikes are off center they can also cause light strikes. 

 

Timing is on.  Again, that mess that was my first revolver (TRR8) was a complete shitshow and didn't carry up on something like four or five of chargeholes when I bought it.  I didn't know any better at the time.  Now, it's one of the things that I check immediately.  

 

37 minutes ago, alecmc said:

Also , check to make sure that the hammer is making it's full stroke back, double check to make sure the hammer is actually transitioning off the double action sear , to the double action cam on the hammer , and falling off from there. If you removed too much material from one surface or another it may be falling early and not having it's full potential momentum to light off the primers

 

Now, this might be interesting (...as in "hang him, he's a witch"...), but I have been experimenting with removing the double action cam surface.  Slightly shorter throw for the hammer, sure, but a little more "buffer" before trigger bottoms out.  The first hammer I tried it on was an Apex and it seemed to work well, so I tried it on a couple "Carmonized" hammers.  I've got about two or three thousand rounds thru a 929 set up this way.  

 

The way I look at it, with the problem 929 it should have at least been reliably detonating Federals at some point with a "Carmonized" hammer set so damn heavy.  

 

I'll try a "Carmonized" hammer with the double action cam surface intact (...what, exactly, is the proper name for that?) and see if that produces different results in the problem gun.

 

Thanks.

Edited by Justin M

Share this post


Link to post
Share on other sites
3 minutes ago, Justin M said:

 

but I have been experimenting with removing the double action cam surface.  

 

 

I'm no engineer , but IMO this is counter intuitive for getting the best possible results.  I cant say 100% but i was under the impression that aftermarket hammers like the Apex and TK have slightly different geometry so that the DA stroke is a touch longer over factory.  More travel, more momentum, better ignition. That whole E=Mc2 thing..or something.

 

From what i've read those short stroke DA triggers were popular back in the day - shorter pull , but much heavier trigger. 

 

You cant have both. 

 

 

Share this post


Link to post
Share on other sites
3 hours ago, alecmc said:

 

 

I'm no engineer , but IMO this is counter intuitive for getting the best possible results.  I cant say 100% but i was under the impression that aftermarket hammers like the Apex and TK have slightly different geometry so that the DA stroke is a touch longer over factory.  More travel, more momentum, better ignition. That whole E=Mc2 thing..or something.

 

From what i've read those short stroke DA triggers were popular back in the day - shorter pull , but much heavier trigger. 

 

You cant have both. 

 

 

I am an engineer, and I'll say with certainty that unless you did major surgery to alter the geometry of your revolver action, shortening the hammer travel will require a heavier pull.  I experimented with these things myself and have settled on the opposite of your approach for mechanical advantage and firm primer strikes.  I used to run something in the mid 4# range but actually run a 6.5# gun now.  

Share this post


Link to post
Share on other sites
12 minutes ago, Alaskan454 said:

I am an engineer, and I'll say with certainty that unless you did major surgery to alter the geometry of your revolver action, shortening the hammer travel will require a heavier pull.  I experimented with these things myself and have settled on the opposite of your approach for mechanical advantage and firm primer strikes.  I used to run something in the mid 4# range but actually run a 6.5# gun now.  

 

I agree with that, however, I don't know what the magnitude of change is.  A degree or two of hammer rotation vs a hammer that has 70% less mass.  The calculus for me is this: Is the slightly heavier pull worth the "extra" room before the trigger comes to a stop worth it.  It seems to be worth it for me - at this point.

 

I didn't get a chance to look at the problem 929 this evening.  Too nice of a day to stay in shop, fired up a scooter and went out for a ride.  Likely tomorrow.  

 

I think, and to be clear - I have about zero revolver experience, that we're discussing a couple different things here: 

 

1. The problem with primer ignition (and trigger pull weight) on the "problem" 929.

 

2. My experimentation with removing the double action "cam" feature on the hammer.

 

I can split the thread, if folks would like to discuss removing the double action "cam" feature.  I think it would be interesting to understand experiments/approaches other people have pursued.

 

Share this post


Link to post
Share on other sites
52 minutes ago, Justin M said:

 

I agree with that, however, I don't know what the magnitude of change is.  A degree or two of hammer rotation vs a hammer that has 70% less mass.  The calculus for me is this: Is the slightly heavier pull worth the "extra" room before the trigger comes to a stop worth it.  It seems to be worth it for me - at this point.

 

I didn't get a chance to look at the problem 929 this evening.  Too nice of a day to stay in shop, fired up a scooter and went out for a ride.  Likely tomorrow.  

 

I think, and to be clear - I have about zero revolver experience, that we're discussing a couple different things here: 

 

1. The problem with primer ignition (and trigger pull weight) on the "problem" 929.

 

2. My experimentation with removing the double action "cam" feature on the hammer.

 

I can split the thread, if folks would like to discuss removing the double action "cam" feature.  I think it would be interesting to understand experiments/approaches other people have pursued.

 

If you like the result I say try it for a while, everyone has their own personal preferences.  Unless you changed the engagement angles significantly, were talking about changes in the range of ounces.   Two main things appeal to me about have the slightly longer DA pull and a heavier trigger.  The first being more reliable ignition (if everything else remains fixed), and the second being a snappier return.  After increasing my hammer spring tension a touch, I've never had a light strike.   Similarly, it's more tolerant to dirt and grime with the extra hammer spring tension.  I've had it so dirty the cylinder doesn't want to spin free, and it still goes bang every time.

 

As for the rebound spring, in certain circumstances I will death grip my gun to run it faster, or to stabilize it for longer/tighter shots.  That extra spring compression is helpful in both instances.  I have a tendency to short stroke a lightly sprung gun.  I like having some reasonable pressure on the trigger at all times, so the extra spring tension is worth it to me.  

Share this post


Link to post
Share on other sites
11 hours ago, Justin M said:

I can split the thread, if folks would like to discuss removing the double action "cam" feature.  I think it would be interesting to understand experiments/approaches other people have pursued.

 

 

I would like to hear more about this.  I have no idea what this is referring to, but I'm always up for learning something new about revolvers.

Share this post


Link to post
Share on other sites
On 8/6/2018 at 9:38 AM, Justin M said:

I have developed what I believe is a fairly straight-forward method to get to a 4lb trigger on a N-Frame S&W.  I'm a pragmatic guy who relishes in routine.  I used a 4" 627 to develop my method so as not to screw up any of my "race" guns.  Once I had the process, I applied it to a couple of 929s and 627/327s.  No issues at all.  I suspect this is very similar to how everyone else does it - no new or novel approach here.  All parts get stoned and/or hit with the Foredom (big Dremel, sometimes it's a Dremel - if that's closer on the bench), an 11lb rebound spring cut down between 1-2 coils, a Wilson mainspring bent to my particular pattern (I've snapped two S&W mainsprings, so I refuse to use them any longer), a X Frame cylinder stop spring, a Cylinder & Slide firing pin (against all recommendations), a snipped firing pin spring, and a 175-200gr "Carmonized" hammer.  All guns, so far, are reliable with Federal 100s - plus or minus a couple ounces of 4lbs.  I usually end up moving the pull weight up to between 5 and 6lbs because I happen, for whatever reason, to shoot better points with a slightly heavier trigger.  

 

So, buddy asked me to "Carmonize" his hammer and get his new (to him) 929 ready for USPSA.  He wants to use Winchester primers, because, um... not sure, but that's his thing, right?  I go about my routine to get to a 4lb trigger figuring I'll get it set up at 4lbs, make sure it's reliable with Federal 100s, then up the mainspring until it reliably fires Winchester primers, and balance out the rebound spring. Gun refuses to reliably fire Federal 100s at 4, 5, 6, ... all the way up to about 10lb.  It'll fire some, but not all.  It'll fire some, but not all Winchester primers at the heavier settings as well.  Of course, match in the morning, because that's how this usually goes, right?!.  I take out my beautiful, super-light "Carmonized" hammer and throw in an Apex hammer and it starts to work, but still at the heavier settings.  Maybe 8lbs give or take.  

 

I'm having hime come back this afternoon to try out an Apex pointy firing pin and to check headspace.  I cannot figure out what else it might be.

 

My questions: 

 

1.  On the Apex pointy pin, why pointed?  All things being equal, will that pin give more reliable ignition than a stock or a similar (rounded or blunt nose) firing pin?  

 

2. What else could be going on here?  There's no drag on the "Carmonized" hammer, the Apex hammer, the firing pin, etc.  Hammer block is laying on bench.  Not more than .002" end shake. Not sure where to look.

 

3.  Unrelated, I think, but still might inform some of this: Why does the Apex .22 hammer have more mass?  If lighter is better for hammers, why does this change from rimfire?

 

Man I'm looking and I can't find a different part number for the X frame cylinder stop springs compared to any other guns. What's the difference and where do I find one?

Share this post


Link to post
Share on other sites
12 hours ago, swordfish said:

Man I'm looking and I can't find a different part number for the X frame cylinder stop springs compared to any other guns. What's the difference and where do I find one?

 

You probably talking about the Extra power Cyl stop springs, you can get them at Wolff Springs here:

 

https://www.gunsprings.com/SMITH & WESSON/K, L, & N FRAME/cID3/mID58/dID264#448

 

I wouldn't bother unless you are trying to alleviate some form of cylinder skipping. 

Share this post


Link to post
Share on other sites

I moved some comments from here to the Vendor Tent area.  We don't discuss purchasing products, or selling them, outside the Classifieds or the Vendor area.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×