Sight Spline Cut?

[Michael Petrov]

Did the early rifles have a square end deeper cut than later ones? I have seen a few sporters with the cut filled like this one and it’s square on the end. Later rifles have more of a “V” notch.

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[John Beard]

The sight spline is actually a drilled hole.

The Rear Sight Fixed Base was aligned and pressed onto the barrel. The barrel was then placed muzzle-down in a drill press and the spline hole was drilled in the seam. A round pin was then driven into the hole.

Knowing Springfield, they probably drilled the hole, then precision reamed it to size for the pin.

The bottom of the hole should have either a cone shape representing the tip of the drill bit, or perhaps a flat shape from the ream.

FWIW.

J.B.

p.s.,

Nice rifle! Thanks for the pictures!

[Michael Petrov]

Thanks John, Now I understand and it looks like they did this one with a end mill or flat bottom drill of some sort. Seems I only see these on very early rifles.

[Chuckindenver]

to answer why some look sharp on the ends.
when drilling said holes, the bit will likely follow the softer metal.
and might have wondered at the end, when the base is removed it will look sharp on the end.

[John Beard]

Thanks John, Now I understand and it looks like they did this one with a end mill or flat bottom drill of some sort. Seems I only see these on very early rifles.

In their annual reports, especially the earlier ones, Springfield continually commented about making changes to reduce production costs. I speculate that they perhaps may have eliminated the reaming operation and settled for a simple drilled hole. After all, the sight base was a tight press-fit on the barrel and the pin was just an added precaution against rotation. The tolerance of a drilled hole had more than sufficient accuracy for that application. And once installed on the receiver, the pin sure wasn't going to fall out!

J.B.

[Michael Petrov]

Thanks John, that makes the subject clear. I just got the new Silvers pad on the rifle yesterday now off to the range.