On Monday, 20 shots into a silhouette match, the elevation screw from the rear sight came off and landed on my chest.
Hmm, thinks I, that could be why I haven't been hitting the targets!
This is a custom made bolt action Unlimited gun, and while the sight does not have a maker's name on it, I THINK it is a BoMar.
After removing the sight, I noticed that there is a small 5 sided nut into which the elevation screw fitted. The threads inside this nut are badly worn, not really surprising as this gun has been used for 25 years, and while my loads are relatively mild, the previous owner would have had the 308 stoked up a bit.
I measure the diameter of the screw to be 0.11", so that should make it a No 4.
However, the tpi is much, much finer than the expect 48 tpi.
With the calipers set at 0.1", I count 8 threads, so 80 tpi!
I don't have a 4 x 80 tpi tap to be able to make a new nut, and I reckon it will be very difficult to find one here in Australia.
So I am asking for help.
If there is someone here who has the correct tap, I would really, really, REALLY appreciate it if you could drill and tap a few holes in a small piece of 1/8" flat bar and mail it to me.
Naturally I am willing to pay, and I will also buy you an adult beverage or three next time you visit us here DownUnder.
Thanking you all in anticipation.