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