No.1 Nk3 trigger work. Where to start.

[30Three]

newcastle, have you checked to see if the cocking piece thread is loose on the firing pin? I don't mean unwound; but maybe a worn thread so there is unwanted movement. That will cause possible trigger issues.
I had this issue with my No1 MkIII*. So I followed Peter's advice and tinned the firing pin thread with solder. While it's still molten, use a soft wire brush to remove excess solder.
Refitting the cocking piece will be a good tight fit on the threads; removing any slop and improving the trigger's regularity.

[newcastle]

Is the long thin bit of the cocking piece supposed to be parallel with the firing pin when it is screwed in? I assume it is. I have just attached a couple of spare cocking pieces to this firing pin to test and with each one the firing pin is not parallel and diverges from the CP when the cut out for the screw is aligned correctly. If not aligned correctly and 180 degrees off, the pin and the cocking piece converge slightly.
I reassembled the original bolt and worked it with the 180 degrees out and the CP does not hit the buttsocket. I must conclude that the Firing pin is in indeed not straight. I suspect that along the line this rifle was shoved back together just to move it on and I've ended up with it so this'll be fun and an education to try to put it back into correct condition.

[Bruce_in_Oz]

The old "bent striker in the SMLE trick". That will certainly cause mischief.

Also remember that thread on the tail of the striker is there to stop it escaping. The precision-ground parallel immediately forward of that thread is the key to how rigidly it is attached to the cocking piece. The dimensions (and tolerances on teh 1/4 inch hole in the cocking piece and the diameter of the striker are such that it is a VERY close fit and this keep them from "wobbling".

[newcastle]

Attachment 110497Attachment 110498Attachment 110499OK so the update here. I've straightened the trigger guard (was bent), replaced the sear (original bent) and trigger (original filed down) and replaced the draws with oak per Laidler instructions, strengthened with wooden pins in from the left and right of the foreend. There was an existing threaded brass rod through the rear of wood which I elected to keep though it made the operation more complicated. Some photo's attached (though I forgot to take final pics). Rifle now has a two stage trigger with no long pull to fire, and no gap between foreend and buttsocket.

Now I just need a straight striker which I need to get from BDL and to stain the ends of the wooden pins and finish the wood.

[browningautorifle]

threaded brass rod

You know that stuff is available, right? Bet some of these guys have a couple around too. It's done now though...