I have not removed a long blade from any of my 99's but there is a factory (blackened German silver) on eBay that is grooved. I shouldn't say that all long blades or that the long sight bases were all grooved as I can't say for sure.

https://www.ebay.com/itm/Savage-99-...6?hash=item365a0b81b6:g:QIMAAOSwuMFUdcas

Savage...never say "never".
Rick...

Join the NRA...together we stand, divided we fall!