Lyman trigger Adj.

[Shootrj2003]

 Does anyone know the size desig.  Of  the trigger adj. screw on a Lyman GPR.?I need a longer one,there is a Lawyer stuck on the end of mine and of course this has rendered it useless.

[Old Salt]

When I had my GPR I used a countersink on the trigger plate to allow the screw to travel futher.  It worked fine.

[smylee grouch]

Did the same thing as Leo on two Lymans and it worked ok, you only need enough for a couple of turns.

[LRB]

   There is a good chance you might find one at ACE hardware, in their specialty bins. It is likely metric.

[Hungry Horse]

Go to your local auto parts store that carries socket head cap screws. they are grade 8 and come in all the fine sized. just match the one you have to one with more threads.

                       Hungry Horse

[Shootrj2003]

No luck in any of the local auto or hardware stores.,the countersink idea sounds good and makes sense I'got one more store that's open tomorrow if I can't get it there I'll go the other route ,I searched every screw I have ,I've got five exactly the same length as the screw that is in it,the longer ones I have are just enough off they go in two or three threads and stop so they must a small fine thread SAE or something,I scavenged another that was an adjustment screw on a lock sear I have but it,although the right length was one size too small ,!without setting it this thing is about 8 lbs,it's off my scale anyways. Thanks guys

[WadePatton]

there are some really close thread counts in the little end of SAE screws, and those would probably act as you describe.  re-tap the hole is another option.

[Bob Roller]

You are probably dealing with a FINE pitch METRIC thread on that Lyman
rifle. IF the diameter of the screw is around .107 to .110 in diameter,rethread
the hole to American 4x40 or 4x48.
I make an interference thread for triggers I make and they stay put.

Bob Roller

[Dave Dolliver]

The thread size is 2.5 mm diameter by .45 mm pitch.  I got mine at Ace Hardware and have replaced quite a few for customers.  It sometimes requires a bit of loc-tite on the thread to keep them from slipping.  The "hardware store" threads are not as tight as the Lyman threads.

Lyman salesman at SHOT Show told me years ago it was a liability fear that caused them to make them short.

Dave Dolliver

[Shootrj2003]

I was trying actually reduce the unset weight of the trigger ,I read it several times but ignored what it was saying,the screw only adjusts the set weight ,the set weight is right at 1 1/2 lbs now,this isn't bad,what  I want to do is reduce the unset weight to around 3-4 lbs .I took the lock apart after making a spring compressing tool pictured to me by another guy( Bigsmoke),I polished the sear and sear notch with a searstone and a couple of other areas which made it much smoother pull wise but did not really do anything for the unset weight of pull,I did not think it would,I think I have to trim a coil or two off the main spring for that,I don 't see any other way,I ordered a new one today for experimenting in that direction!
I did notice that the sear tumbler shaft is .308 and the hole is .315 so there is some slack there but I don't think I'm gonna go that route(welding and redrilling) First thing,I 'll trade springs just to see if that makes a difference,any body here work on these locks much? Any help is good thanks.

[LRB]

  Reduce the sear spring power. Reduce the amount of sear engagement by blocking the notch, which can be done by a few different methods. With set triggers, the front trigger weight of pull unset, can only be adjusted in the lock itself by reduction of spring power, and polishing all places that move against another. With the set trigger adjustment, or the sear engagement in the lock, you really don't reduce weight of pull, but reduce percieved weight of pull by reducing travel. In either case, the acual weight of pull can only be reduced by reducing spring power. In a single trigger set up, the leverage position of the trigger bar on the sear bar will determine much of the pull weight, but this is not so true with set triggers.

[Shootrj2003]

Did I understand. You to mean the sear spring,as the small spring inside the sear plunger? Or did you meanthe large main spring I bought an extra of both for experimentation purposes..

[LRB]

  I mean't the sear spring inside the plunger. It's only job is to return the sear to the tumbler and only needs enough power to do this in a positive manner. It is a cut and try proceedure. It must retain enough power to leave the sear a little snappy, but in most locks is over powered. When you pull the trigger you are having to overcome this spring plus the back pressure from the tumblers main spring if it is cocked. You never mentioned flint or cap. If flint you probably do not want to lighten the main spring, but if cap, you might lighten it up a little. It used to be fairly common that some manufacturors, especially foreign, would use very heavy sear springs to over come poor sear/tumbler angles, by relying on spring pressure to hold the sear in place, rather than proper angles. If your angles are correct, the sear will stay in place in full cock from main spring pressure on the tumbler even with the sear spring removed, and will not trip if you push on the hammer/cock. Only when you trip the sear should it release

[Shootrj2003]

LRB,
Thank you for your assistance,I had suspected that little spring might hold the answer that's why I ordered one also ,but it 's always good to have someone light the way a bit.
                                                       Shootr

[Shootrj2003]

This rifle is a flintlock,sorry,I should have mentioned that.

[Shootrj2003]

LRB,
  I reduced the sear spring power by replacing it with a spring from a pen which fit and functioned with a bit of tailoring,originally the lock tripped at around 6-8 lbs unset and at 1 1/2lbs set,now it trips at 2 lbs unset and 1 1/4  lbs set ,this is just a bit too light for the unset pull but at least I know I'm on the right track it passes all safety tests and actually works very well and breaks very clean,but most of all it's safe but I'm gonna go to the gunsmith I know and see if he has something in between,thanks for your help on this.