RugerSociety.com

Like many others, I prefer open sights and enjoy looking at the Ruger offerings. I've read in the Reference about some that had slotted front sights but I don't think I've ever seen one.
Is there a story about why and how, apparently, a very few got slots for a hood? Did Ruger supply or make a sight hood for those guns and, if so, how rare are they? Are they the same as the non-slotted sights, otherwise? Is there a known SN range beyond the published 70-10491 high number? Would a Letter indicate the unique sight?
Thanks. Lots of questions, I know. Fascinating stuff.

Ruger evidently had a bunch of the slotted front sight bases made before they decided they weren't going to have the hood as a regular production accessory. Supposedly there were only three of the hoods made.
So, as the parts bin theory goes, the slotted front sight bases get used as they are grabbed from the box of front sight bases.
The slotted base is usually found on the #1 rifle. But as mentioned, can be found on the M77 into at least the 70-10xxx range.
Another thing to consider, the majority of early Number 1 rifles and M77 rifles did not have sights... so evidently took a while to finally use the small production of slotted sights up.
Chet15