Bridle screws and trigger pull

[connerm]

new r.e. davis lock on my flinter. Brand new lock so I wanted to see how it would work. Dry firing with a plastic flint told me trigger was very heavy - every bit of 10 lbs. Made sure things were lubricated and live fired it 10 times. Ignites perfectly and accurate too, but trigger was too heavy. Took it apart at home and very lightly polished some of the contact points on the tumbler and sear. After reassembly and lubrication, I had to leave the top and bottom bridle screws a tiny bit loose for the sear to move freely. Is it ok for these screws to be a little loose? As I understand it, the screws won't back out because the sear and main springs keep tension on the whole affair acting like lock washers. Respectfully submitted.

 

[rich pierce]

yes, they can be loose. The sear must be free to pivot w/o tension when there's no sear spring pressing on it. You can also carefully stone a bit off the sear to reduce its thickness.

I found I needed to square the full cock notch a bit on my Davis lock. The sear was sort of levering the tumbler a bit. Now I have about a 5 pound pull and it's crisp.

 

[LRB]

You should also reduce the power of the sear spring. I too have found some Davis locks with a poor sear notch angle. The sear spring only needs enough power to be safe and reliable. Generally they are much too strong on most, if not all, locks you buy.

 

[Tom Curran]

When you lighten the spring, don't shorten it! The tip of the spring should be right up near the pivot of the sear. The farther away from this pivot, the more leverage the spring has on the sear.

Sadder but wiser dept.

I like to stone the sear so that it stays in the notch WITHOUT the aid of the spring. Too wide of an angle, and the sear will pop out when IT wants to, not when you decide.

Too much undercut, and the sear will have to rotate the tumbler before releasing the tumbler. In this case, the sear is working against the mainspring and the sear spring.

Most new locks have to be fine tuned. I have, almost without exception, tuned the sear spring, sear and tumbler notches on all the new locks I have worked on.

Chambers does the nicest assembly job I have seen so far. All bearing surfaces have been polished, fits are good, heat treatment all done properly, etc.