Creeping trigger

[Billnpatti]

I once got a Pedersoli Pennsylvania rifle, I think it was called a Silver Hawk or Silver something, I don't remember the exact name. It was quite pretty with the extra (silver? or German silver?) inlays and it was pretty pricy compared to the regular Pennsylvania style rifles made by Pedersoli. Anyway, it had a trigger pull from Hell. It was a two finger trigger pull. I took the lock out to see what the problem was and it turns out that the full cock notch was at the wrong angle and way too deep. When I would pull the trigger, it actually made the hammer move back just a bit before going off. I solved the deep notch problem by soldering in a brass shim. This helped quite a bit but it did nothing for the incorrect notch angle. I didn't have the equipment to properly file the notch angle so I did not mess with that. I sure liked the looks of the rifle but didn't like the lock problem so, not having the equipment to correct the problem, I got rid of it and bought a rifle with a good trigger pull.

 

[crockett]

Is the notch area heat treated or case hardened? If it is heat treated it seems you could file the area but if case hardened- you'd file away the hard surface.
I like the pin but there is a definite plus on a shim epoxy glued in place or with a low melt solder.
If you drill, it would be slow and stop- don't over heat- if that is doable.

 

[Billnpatti]

I truly don't know how Pedersoli hardens their tumblers but I would think that heat treating would be a better and more cost effective way of doing it. I was going on the assumption that the tumblers were heat treated. I first thought of drilling and tapping the back of the notch for a tiny set screw. That would have made the sear engagement adjustable. Only problem was that I didn't have a carbide bit of the proper size nor a tap of the proper size. The shim method was more expedient for me. Since I didn't have a jig for filing or honing the tumbler full cock notch to the proper angle, I chose not to mess with that since that is a very touchy area to mess with. I don't mind polishing the full cock notch but I don't want to mess with changing the angle unless I have the proper equipment.

Soooo........I solved my problem with that rifle by getting rid of it and getting a rifle that had a proper trigger pull. Problem solved. :wink:

 

[Artificer]

The Full Cock Notch at a backward angle, that makes the trigger pull harder as you pull it because you are cocking the hammer/cock, was a VERY common problem with Repro WBTS Military Musket Locks and to a lesser extent, Original Springfield Locks - when I first began doing Trigger Pull Work on them in 1974. I have not been able to document this and Lord knows I have tried by a lot of research, but I think a SMALL amount of backward angle was designed into the Full Cock Notch on original military tumblers as a way to ensure longevity of parts usage and perhaps even a safety feature. The latter due to adrenaline flowing in combat might otherwise cause a soldier to pull the trigger before he meant it. I have looked at a LOT of original M1841/42/55/61/63/73 Tumblers and they all seemed to have just a little bit of that rearward angle, though nowhere near as much as the Replica Tumblers.

When I started doing trigger jobs on those muskets, triangular diamond needle files were not easy to come by and very expensive. So for quite some time we used Medium India Stones to change the angle and then Fine India and Hard Arkansas stones to polish them. Wow, that took a lot of time on the repro tumblers. Diamond files really speed up the work, but one has to be careful not to cut too much.

Pedersoli did not come out with WBTS guns until after I stopped going to the NSSA nationals around 2005, so I can't say whether their tumblers were case/surface hardened or through hardened. By the time I did the Trigger Pull on my Circa 1975 Pedersoli Brown Bess, I had already begun rehardening and annealing the Tumblers and Sears after I worked on them - but that is beyond what most home hobbyists are capable of doing.

It would be GREAT if buying a new Tumbler would ensure the Full Cock Notch angle would be at the correct angle, but unfortunately the replacements are usually the same or worse.

Gus

P.S. I would expect to HAVE to reharden and anneal the tumbler on most Italian Repro Tumblers, after correcting the Full Cock Notch Angle.

 

[crockett]

Amen, folks forget that the notch is rotating so the angle that's critical is that when the sear nose and notch make contact. Getting the angles correct can be very tricky.
BTW- a lot of side by side modern shotguns are very similar. The sear is a teeter-totter and instead of a tumbler the notches are on the underside of internal hammers but otherwise the idea is very much the same. If a replacement sear is installed that is too long -it rotates the hammer farther back and the angle of the notch changes from flush or undercut to sloping- not good.

 

[Artificer]

I recently solder a brass shim on the tumbler on a long range ML target rifle. Took the creep out and lightened the trigger pull. Did not lighten the trigger pull as much as I was hopping.

Fleener

I shimmed a wide variety of tumblers from different original and repro guns at NSSA Spring and Fall National Shoots. I found it was not unusual that even with repro guns of the same type, it was not uncommon that different thicknesses of shims were necessary on guns of different makers.

I finally got a pack of Machinist's Brass Shim stock that went from .003" up to .022" in increments of one or two thousandths sheet. Eventually, experience taught me what size of shim worked best with the tumblers of different makers and with different types of guns.

If the shim you added did not reduce the trigger pull enough for your liking, you need a thicker piece of shim stock than you used. (I sometimes had to use two or even three thicknesses of shims to learn what worked best on each tumbler.)

Also, it was not uncommon that I had to use a shim that was initially TOO thick and reduced the trigger pull too much because other thinner shims were not thick enough and there wasn't a "perfect size" in even that large variety of shim stock. So with the "too thick" shims I sometimes had to use, I then had to file them down a little at a time and try them for trigger pull, file and check, file and check - until I got the minimum trigger pull weight I wanted. You just have to be careful that you only file on the shim and not the face of the full cock notch.

I'm sorry but since I have never shimmed a Roller Lock Tumbler, I don't know the thickness size is required to get it to what weight you want. My most common thickness sizes I used on Military Tumblers was from .015" to .022", though that may or probably is too thick for a civilian lock.

Whatever thickness shim stock you used, it sounds like you need one .002" to maybe at most .005" thicker than the one you used, unless the first shim did not reduce the trigger pull weight much at all.

Gus

 

[fleener]

I am currently in Milwaukee for the week. Perhaps this weekend I can post a picture of the lock I added the shim

Fleener

 

[Artificer]

I am currently in Milwaukee for the week. Perhaps this weekend I can post a picture of the lock I added the shim

Fleener

That would be good, but it would be very important to have the thickness of the shim stock you used on it, as well.

Gus

 

[fleener]

here are pictures of the Roller lock. You can see the .010" brass shim that is soldered on.

If I remember right without the shim it was around 6-7 lbs and had creep.

The trigger pull was a little less than I thought, at 3.25lbs. I prefer 2-2.25lb triggers for my LRML.

Fleener

 

[Artificer]

Since you already used a .010" shim and got it close to what you want, I would try a .012" shim to replace it. It may be not quite enough or too much thickness. If too much thickness and the trigger pull is then too light; then you can file and check, and file and check until you take off just enough to get the trigger pull weight you want.

Gus

 

[Pete G]

Beautiful work on that lock. You're lucky to have it.

 

[crockett]

Thanks, I didn't know the actual pull could be reduced, I thought you could only take out the creep aspect.
BTW- the lock work on many side by side modern shotguns is somewhat similar but instead of the shim a dovetail is cut into what is the hammer on the shotgun lock and a plug driven in and filed down. BUT the psi on a lot of solder is such that the shim is probably the far more practical answer.

 

[Artificer]

A shim, or screw or bump of metal reduces the amount of sear engagement surface and that's what causes the trigger pull weight to go lighter.

The absolute heaviest trigger pulls I have ever found on traditional rifles in this forum's period was/are Smith Breechloading Carbines. This Carbine "breaks down" like a single barrel shotgun. What may resemble a brass front trigger is actually a lever that is pushed upwards to break the rifle down. http://www.rockislandauction.com/photos/52/p_standard/MGI576-L-F2-L.jpg

I have checked trigger pulls on many original Smith Carbines with certified trigger pull weights and they run as high as 22 to an almost unbelievable 28 pounds trigger pull weight. I have no freaking idea how a Cavalry Trooper was expected to hit anything with that heavy of a trigger pull, but it seems it was meant as a safety feature so the rifle would not go off until the Trooper REALLY wanted to fire it and especially from horseback. Yet the proper sized shim will get the trigger pull down to between 3 1/2 and 4 pounds for a very nice trigger pull. The only problem, though, is you have to disassemble and reassemble the rifle so much to get the trigger pull down to just the right trigger pull weight.

Gus