I have a couple of No4 Mk1's with trigger problems and I am confused as usual.
One, a Savage Mk1* sometimes sticks at half cock on (possibly timorous) second stage trigger pull. A straight edge on the bottom of the cocking piece shows a significant 20 or 30 thou gap at the sear interface end whereas my more pristine rifles have cocking pieces with little or no gap.
The other, a POFicon No4 Mk1 has a replacement bolt(My MkII bolt works fine in it but that has a good cocking piece) and if first stage pull is released before firing, the bolt travels upwards resulting in a single stage trigger at the next pull.
I realise that these are typical No4 problems but I am not sure how or whether to fix them.
1)With a straight edge along the bottom of the cocking piece; Should there be any gaps?.
2)What is the reference point for the height of the sear with respect to the body(action) and what is the angle of the sear from that refence point?.
3)These problems could be fixed in several ways, but which is correct and/or acceptable and in which order;
a)New bolt or cocking piece or possibly sear.
b)Grind of the back of the sear to let it sit up slightly and grind a bit off the lower lug with a bit of grinding of the trigger bumps.
c)Check the trigger guard is sitting flat. Should the trigger operation be checked with a standard length collar without the wood fitted, or should adjustments be made after woodwork is fitted and collar adjusted. (I'm Having a problem with that too).
d) Do sear lengths/heights differ much?.
e)Do the Bumps on the trigger differ and/or sometimes need adjusting?.
g)Is it OK to have a single stage trigger pull by removing the first bump on the trigger?.

Finally, is there anyone out there with a stock of No4 bolt bodies, sears, cocking pieces etc at a reasonable price so that I don't have to spend months on auction sites?.
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