More Pics To Go With Worn Hammer
Posted 10 January 2005 - 07:57 PM
Posted 11 January 2005 - 07:10 AM
If it were me I would do two things, first inspect the inside of the reciever very carefully for excessive wear anywhere. It is a Westie, so I doubt it was ever cut and rewelded (my first thought - misalignment somewhere). Second and easiest (do the inspection first!) is to chuck all of the interbnale and put in a set of replacements, they are cheap enough.
My guess is someone who already did this on your gun (it could have come with GI internals, what is the S/N range?) may have used worn out or abused parts, thinking if they are GI they are automatically better than what was in the gun.
PK could probably add more here if he recognizes this type of wear pattern as a specific fault, but I do not. My only other guess is it was run a long time without oil (Westies don't have oilers, do they?).
Good luck getting that thing back on the range!
Posted 11 January 2005 - 08:04 AM
Did you put in these parts yourself when they were in good shape or did you receive the Thompson with these parts already in them?
Posted 11 January 2005 - 09:15 AM
I don’t see the photo of the back side of the hammer, but the FP and receiver contact surfaces look OK. There are two areas (at 90 degrees) on the back side of the hammer that can contact; one is the seat with the bolt, the other can be hit by the actuator in extreme circumstances. I think I see a bit of raised metal in the bolt photo at the point of hammer contact. This concerns me because both of these parts are very hard and not prone to upset. The only force normally applied to this juncture would be that of the FP spring and any shock force when the bolt is arrested by the buffer in full recoil. The latter should not a problem unless the bolt is moving much more rapidly than it should be.
The firing pin head looks quite normal for one used in a bolt with a sharp edge on the fire pin hole, or undue roughness in the start of the hole; dressing with a bit of emery should solve that one. If the hammer is rotating to far to the rear (as may be the case), it could also cause this condition. The hammer actually pushes the FP up, as well as in. I like to grease the head of the FP and the hammer contact surfaces in any event.
The lock shows a bit of rubbing caused by off an off center bolt pock in the receiver, but the back surface of the locking ear looks fine.
I am not sure what I am seeing on the inside of the bolt (far side of the photo) next to the forward edge of the locking slot, but I don’t like it. Nothing normally in this area would cause the upset I think I see.
All of the parts in question used in WH production were GI; I do not believe WH made any of these parts at any time.
Just because you get a NOS GI part does not mean it won’t have edges or areas that need a bit of touch up to be really good.