I have a never fired Lyman Great Plains rifle that is not working properly. If I pull the set (back) trigger the hammer falls to the half cock position when I pull the front trigger. If I just pull the front trigger without pulling the set trigger the hammer falls all the way. I've cleaned and lubed all the moving parts and tried adjusting the screw on the triggers but nothing seems to work. Any ideas would be appreciated.
Flintlock hammer not falling all the way
- Thread starter dynabase
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The fly is in backwards or frozen in position.
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Check to see if the fly is working
Larry
Is the fly even there?
Looking at your lock, @dynabase, there should be a small triangular piece of metal (the fly) that covers the half cock notch at about the #11 tumbler. The fly is either frozen in place or missing. When the lock is released with the set trigger, the sear rides along the tumbler. The fly covers the half cock notch and lifts the sear over the half cock notch. When the lock is released unset, you are holding the sear away from the tumbler and over the half cock notch.
Remove your lock and look for the fly. Make sure it moves freely in the recess for the fly.
ohio ramrod
75 Cal.
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As stated the problem is in the fly operation. Besides making sure the fly is moving correctly,test the lock out out the gun ,and look for any wood that could be interfering when the lock is in the gun.
I don't which manufacturer made your GP but the Investarms version I have the trigger was garbage when I was assembling the kit I replaced it with a Davis trigger.
I had to make a new fly for a lock at one time; the original had worn down to the point that it would no longer carry the sear reliably. Find someone nearby who has a similar lock and compare the flys.
hanshi
Cannon
Good advice in the above posts. I had a problem once with a lock containing a fly that was not needed - just a single trigger. The fly was too low at the tumbler and yes, it went to half cock with a trigger pull. A friend took the lock and removed the fly altogether, the lock has worked perfectly ever since.
Some when assembling a lock will also make the bridle too tight, "trapping" the tumbler and/or fly, if the lock doesn't have stop screws. That can render a fly inoperable, so the screw tension can be tuned, or the fly can be thinned.
OK I think I figured it out. It looks like the "fly cover plate" (plate with 3 screws) is bent allowing the fly to ride up and jam. For some reason this only seems happens when it is in the gun. After it happens I pull the lock and the fly is jammed between the plate and #12 what ever that is called. It's the part that the trigger pushes up to release the lock. Assuming I am correct now what? Can I buy a new plate or do I need to replace the lock? What are my options? Anyone know of a good repair video? Since Lyman is out of business I guess warranty repair is out of the question. FYI this is a left handed flint gun.
Lyman is not out of business but the current GPR is made by Pedersoli instead of Investarms. The "fly cover plate" (#2) is usually called the bridle and #12 is the sear. I don't know if you can buy a new bridle or not but try straightening the one you have and check for burs. It's possible to overtighten screw #19 bending the bridle and binding the sear. Check to see if the fly moves freely in the mortise in the tumbler before and after assembling the lock.
#12 is the sear. The plate is called the bridle. And the bridle gets bent when it is the lock mortise? What is bearing on the lock plate in the lock mortise to bend it? Verify that the three screws are tightened to just snug and not causing the bridle to bend. Look for rubbing of the lock plate on the wood. Get the grease pencil, lipstick, soot from a burning candle to put some transfer material on the plate. Install it and see what is rubbing and making marks on the wood. @dynabase may need to remove some wood from the lock mortise.
Lyman is still in business.
Lyman is still in business.
