Decided to get a couple of troublesome Stevens 44-1/2s out of the safe and go "Waltzing Matilda" with them.  Again.

The first is a 47-44-1/2 with set triggers.  It was found with no fly.  I used a homemade fly for years, but occasionally, it would override the halfcock when the lever was cycled, and had to be halfcocked by hand.  No problems otherwise, but I wanted it to work right.

So I got several flies from CPA.  They duly arrived and I've had nothing but trouble since.

I had made a closer fitting hammer screw, so had to drill the hole in the new fly out to fit, but that modification and a little polishing and the thing swiveled on the hammer screw (I guess) like it was supposed to.  But when I assembled the action it would not cock.  It acted like there was no full-cock notch on the hammer.  The sear would go into halfcock with no trouble.

I ordered new springs for the set triggers from CPA and replaced the ones on the gun.  No help.  So back into the safe it went and I went on to other things.

There other is a standard model, with a buggered hammer notch.  I've been gradually stoning it back to a decent pull; no particular issues there.  However, it (like the 47) came without the fly.

I'd recently finished a reline job on this one and did a little more work on the hammer notch.  I figured I might as well put one of the flies on that one, too, as all the models seemed to have them, whatever the trigger type.

So I put another CPA fly (unmodified) on that hammer and it refused to cock; acted like it has no full-cock notch.

I got the other gun out of the safe again and a third (standard) model with a still-extant fly (which cocks, halfcocks and fires fine).  Comparing flies, the replacements seemed a little generous with material, so I did some judicious grinding and filing on the edges of the new ones to better match the outline of the old one.

Still no joy.  Both guns still refuse to cock, although if the hammer on the 47 is back when I tighten the hammer screw, it holds the cock notch fine.  Once it's down, it doesn't catch again.

So now, the 44-1/2 (without a fly) goes to the range tomorrow to see if the trigger pull has been improved and the 47 is back in the safe.

Can anybody tell me how these things are supposed to work?  It looks like the sear is supposed to push the fly up out of the way of the full-cock notch and then ride over it to miss the half-cock notch.  I'm afraid to take any more off the surfaces.

This should be what the fly looks like installed and fitted properly.  Pictures are from an original 44 1/2.

As has been said many time here…make sure the front screw that retains the trigger assembly is not to tight.  Slightly loosen this screw before doing anything else.

Can you feel play between the front trigger and the sear?  When unset.

The other thing I should ask.  Have you tried cocking it with the triggers set?  If still doesn’t catch the full cock, theres a good chance it is the fly.  If it does cock then there’s a chance the spring on the cocking trigger is not balanced properly.
Bob

Chuck brings up a good point of a fixture so I went back and searched pictures for something like that.  Kind of found one which I will show.  But before that I will take a stab at explaining how this all works, with pictures.  Anyone please correct me if I'm incorrect anywhere in this explaination.  I'll do this in several posts so it easier follow.

This is the same photo as I showed before, showing the position of the fly. As shown (#1) it is covering the half cock notch so the sear slides up over and can not catch.

(#2) Is the full cock notch.  With a pin through the hammer pin hole, for alignment, and then rotating the fly toward the full cock notch it should never cover the full notch and will probably stop leaving the tip exposed so the sear can catch as it slides along the bottom of the hammer.

(#3)  Is the surface the sear should always be in contact with so when cocking the hammer it can enter either notch.  The sear is spring loaded to keep it in contact here.

This pictures shows an exaggerated sear position.

#1 is the the set trigger front extension as explained in the last post.  It is holding the rear of the sear high at a steep angle #2.  In this position the sear can not stay in contact with the hammer and engage the notches.

This is what can happen when the set trigger spring is not balanced.  Too much down pressure will raise the extension of the set trigger too high disengaging the sear from the hammer.  This is the reason I suggested setting the trigger to see if it would then cock.
Bob

One more thing.  It’s been awhile since I played with one of these but, I believe the following to be correct.  Please correct me if this is incorrect.

In my reply #3 the fly is shown laying on top of the hammer.  The tab sticking out behind the working portion of the fly is the stop so the fly doesn’t travel past the half cock notch.

The lobe on the opposite side is the stop for when the fly is rotated toward the full cock notch.

So when installing a new fly this all needs to be fitted correctly.
Bob

Bobw thank you for that.  I've got a problem that I think I've narrowed down to the fly preventing the rifle from going to full cock unless the hammer is pulled back very rapidly.  Going slowly, the sear never stays in the full cock notch.  I'm suspecting the fly and your pictures and explanations are exactly what I need.

Chris.

Chuck is correct in all cases….reply #9. Thanks

I corrected the error in reply #7.  That is an important point if a new spring is installed or in a rare case the trigger.

I got interrupted at that point in the write-up and missed some points.  A friend decided to marry his girl friend and need a witness for the wedding application and needed me there pronto….true store!
Bob

Chris/gunlaker, if you haven't already done so, be sure to loosen the front trigger frame screw first.  If the screw is really tight the sear could be hanging up when the hammer is being moved slowly.  Moving the hammer quickly may give the sear/sear spring the inertia too over come the sticking.   Then, if it still has the issue, check the sear spring and be sure it is in position and maintaining consistent pressure on the sear.  Then check the fly.
bob

It seem periodically issues with the 44 1/2, original or CPA, fly and set triggers pop up here.  This is one of the reason I have made an attempt to explain how it works now.  While the system isn’t complicated it does require some careful attention and fitting.

Believe me, while building a 44 1/2 from scratch including the set trigger assembly, I had the opportunity to run into all the issues getting it all to work properly.
Bob

bobw wrote on Aug 28^th, 2023 at 1:19pm:


Bob, just so I understand? in my CPA, if I use the hammer screw as a pivot and assemble it like in your picture, and rotate the fly toward the full cock notch, then it should not cover the full cock notch?

Mine definitely does. 

Is there something that is supposed to limit the travel of the fly to prevent it from rotating far enough to not cover the full cock notch?

thanks,

Chris.

OK,  modicum of progress.  I guess.

I decided to see what I could do on the single-trigger Stevens that I'm also trying to ease the trigger pull on.   Any "lessons learned" would, I hope, apply to the more complicated set-trigger mechanism.

Here's a picture of the notches on the bottom of my hammer, with two unaltered CPA flies set up on the hammer pin in the manner bobw showed, simultaneously.  The outside one is pushed up to block any tendency of the trigger sear to pop into the halfcock notch, as he illustrated and later numbered.  However, the identical one on the pin, down as far as it will go in the slot in the hammer, as (I hope) can be seen, does extend a little into the fullcock notch.  With the hammer and spring installed, it will not cock.

If I was to grind enough of that interference off so that nothing shows below the halfcock notch, I would think it would result in a gap when the fly came up to override the halfcock on firing, and negate its own function, allowing the trigger to slide in there.

(If set, of course. A normal pull on the trigger would keep it out as their hammer fell, which is why the fly really isn't needed with the standard trigger.  Still, as in the case of the other plain original, I want it to work.)

Hope this pic loads.

So; now the denouement, the climax; the kicker; the Big Moment!

I put the hammer and fly back into the gun.  It wouldn't cock.  I turned the gun upside down.  It cocked.  I turned it back rightside up again.  It cocked several times and I snapped the trigger with thumb pressure on the hammer in between.

I installed the hammer spring.  The hammer cocked.  I tightened the strain screw and took it out to the garage, where a box of fired shells with fired primers waited.

Putting a shell into the chamber, I closed the breech and tried to cock the hammer.  Nope!  I turned the gun upside down.  The hammer cocked fine, and I snapped the trigger on the dead primer.  I extracted the shell, put another dead soldier in.  The hammer cocked and I snapped the trigger.  Four more shells chambered, cocked and snapped fine.  The trigger pull will never be great, but it is noticeably better.

It seems if the gun sits around on halfcock, the fly might get a little sticky, so either turning it upside-down, or (as I found) quickly pulling the hammer to full cock (like gunfighters do with Single Action Armies) does the business.  I think I'll so some shooting with it and see if things get better or worse before trying any more grinding or filing.

Not out of the woods yet, but a significant improvement compared to what it was.  That fly looks Cool, but is not Stevens' finest design moment.  Anybody who takes the hammer pin out (for whatever reason) will likely lose the thing down into the innards of the action, from there to fall out on the floor and get swept up with the next cleanup.  Only one of the 44-1/2s I've found has the thing on it.

Bent_Ramrod wrote on Aug 30^th, 2023 at 4:31pm:


Yours sounds like it's behaving like mine now!.  The only way for it to work reliably is to rapidly cock it.

I have a new fly on the way, but over the next couple of days I'll take apart my first CPA and compare them.   

Chris.

I just took apart my first CPA and the flys are definitely a little different in shape.  The way the first one is set up, pressure from the sear looks like it would push the fly out of the way to allow full cock to work nicely.  The rifle that doesn't work properly has a different shaped fly that seems more likely to not get pushed out of the way.  I'm assuming that's how the full cock is supposed to get exposed ( by the sear pushing on the fly and rotating it out of the way ). 

Chris.

I've been trying to catch up with what you guys are asking and doing, but haven't totally comprehended it all.  About all I can do to help, without seeing them, is try to explain the operations and how I believe they work. 

First, the fly can not interfere with the full cock notch at all! 

Also, you may have missed my post about the stops.  Here are couple pictures showing  and explaining them.

Photo #1 Your picture of the flys.  #1 Lobe and the full cock stop.  #2 is the half cock stop, #3 the area the sear slides against to clear the half cock notch (I corrected this arrow to reflect the proper surface better) and #4 assumed hump the sear needs to ride over to get to the full cock notch, once the fly stops.
  
First photo....#4, I do not believe this area or any part of the fly should enter the full cock notch. I believe it should stop between the two notches and the sear rides over it and into the full notch.  If it is locked behind the full cock notch then the sear, being ahead of it, would enter the half cock on firing the gun.

Photo 2, #1 Lobe for full cock stop and #2 is the stop in the hammer.

Photo 3, #1 the half cock stop on the fly and #2 the half cock stop in the hammer.

Bill, I’m sure you have just forgot.

The full build is here.

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Bob

It’s probably me trying to explain how it works that is confusing.  Maybe someone else can explain it better or differently.

I’ll try to simplify checking the fly operation, fixing is another beast.

If you remove the hammer and using the screw to keep the fly in place.  Then holding the hammer in the approximate position it would be when holding the gun in shooting, spur up. Move the fly forward and it should stop where it covers the half cock notch.  When you cock the hammer the sear drags the fly back toward the full notch but should release it before the sear drops in the notch.  You can do the same thing with a finger nail or knife blade and see what happens.  The fly should free fall out of the way so the sear can drop in the full notch….without the fly touching the sear.  Whether cocking the hammer slow or fast the fly should not contact the sear.  If the sear can catch any part of the fly in or out of the full notch it needs work.

Of course we are looking everything in a static state and need to think how all the parts move when in motion.  We are all trying to figure things out with words, where if the parts were in hand it would be much easier to see what is going on.  We are all learning something with this thread and, I would like to see both you guys guns working properly.  

Your comment starting with “This first contact needs to be short”  I believe is correct.

In my opinion the stop #1 is probably ok as long as it is not allowing the lump #4 get too close to the full notch, definitely not into it.  Once the sear travels past the lump the fly should be free and not interfere with the completion of cocking.  As long as the sear doesn’t hang up on surface #3 (I corrected this arrow to reflect the proper surface better), it should cock with no issues.

Bob

After added the above comments I've been studying all these pictures closer.  I'm now more convinced you are correct with the rounding of the surface #3 (I corrected this arrow to reflect the proper surface better).  Looking closer at the original compared to your new fly, this point is much more rounded on the original.  By changing it should not effect the sear sliding past the half notch.  I would change it by rounding or changing the angle until it no longer protrudes into the full notch.  Do this without any change to the length of point #4.  That length is required for the the sear to get past the half notch.  I would take one of your extra flys and make this change.  This goes back to my points that the fly should never protrude into the full notch and the point early on that said the fly was too long.  Just that too long in this case probably only applies to part of the fly.

Most of the time I'm a bit slow at seeing things!

I ground more off the front of the fly I'd already been using for the 47 set trigger.  The lower rear (3 in bobw's numeration on my picture) was now almost gone, leaving a surface almost parallel with the fullcock notch but still protruding into it slightly.

Assembling the hammer with fly and hammer screw could be done with the hammer at full cock, and with thumb pressure on the hammer, the set trigger would snap it.  Subsequent attempts to cock the hammer resulted in a mild bump or snag when pulled all the way back, but the hammer wouldn't catch in the notch.

I soldered a piece of jigsaw blade to the fly at position 1, dressed it down until it fit and turned on the hammer pin in the hammer slot.  This served to hold what was left of the projection on the fly almost completely out of the fullcock notch.  Assembled, it would snag a little more positively when fully cocked against thumb pressure, and occasionally cock if enough upending, tapping, and other maneuvers were done.  However, now, if cocked, the sear fell into the halfcock notch when trigger was pulled.

So I took a new fly and soldered an identical piece of blade onto position 1, grinding it down in front until it would allow the tab 3-4 to move out of the halfcock notch when down.  When cocked, it seemed to snag more frequently going over the fullcock notch, and would occasionally stick at full cock, with sufficient tapping, rattling, turning over, etc.

At this point, lobe 3-4 still projected into the fullcock notch, although it looked like the surface should allow the sear to slide over it and push it up and out of the way.  Assembling and trying to cock resulted in more pronounced snagging and even occasional cocking.  I took the fly and ground a slight radius or rounding on position 3.  On assembly, it actually cocked, and stayed cocked, more often than it merely heavily snagged.

I put the mainspring on and the hammer snagged often and heavily, and cocked occasionally.

I guess some progress has been made, but it mystifies me how this setup can give these problems.  I'll continue to round off the fly at position 3 and see if the full cocking outstrips the snagging and bumping.  Certainly the extra metal at 1 keeps the fly higher in the fullcock notch; I doubt that a thicker piece there could move it completely out while still allowing the automatic halfcock when the action is opened.

All I do know is that I'm getting plenty tired of taking this thing apart and putting it back together.