I like 6 oclock but for the 600 I use what I call a Flat Tire. Push the post into the black just a little. Old eyes are the real problem know.
Question: What width front sight is on your rifle? Some folks like the wider battle sight over the NM size.
For air rifle I use apertures. I didn't find trying to duplicate the service rifle sight picture as effective as following the international guidelines and targets. The hold and follow through training from air rifle is first class.
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