Help with lock replacement

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Feb 8, 2022
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I purchased a used EIG sea service pistol. The lock is pretty crude, meh. But the frizzen is so hard to open that i went and bought another lock. Had a queen anne plate from a previous build. Its really close. Well to my eyes anyway. So i figure what better way to learn than work on it. Can always fab a stock if i ruin this one trying to get the queen ann to fit. Well I'm bound and determined to get this thing to fire. So im stucknow working on two different things.
1. The old lock.
2 the new lock and inlet for it.
1.First question is how to make the frizzen easier to flip open like the quenn ann. Polished the surfaces. Still no love.
2. Secondly, the mainspring hits the barrel down low and the touch hole is to low for the new lock. It sits behind the flat face of the lock that meets the barrel.
Any and all suggestions gladly listened to. TIA.


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Aug 29, 2020
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Grind the frizzen spring thinner to make it lighter. You will have to polish it very thoroughly after you thin it or it may crack. You can also file or grind down the nub on the frizzen where it contacts the spring to make it a littler lighter. It looks pointy on the contact point and flat right in front of that...make it more round.

Also, modern a frizzen spring from Chambers can be made to fit with a little effort.
Oct 31, 2018
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You need to thin the frizzen spring - it's way too thick. You should be able to file it. If a file won't cut it then it's also too hard. When you open the frizzen all the way, any length of spring that is past where the toe of the frizzen touches the spring can be/should be cut off. It appears in the picture that the end of the spring is rubbing on the plate, and shortening the spring will help with that.
As far as the touch hole, you either need to get a lock that fits the gun, weld the existing hole closed and drill a new hole or drill and tap the existing hole, screw in a screw , file it flush and then drill a new hole.