honestly if you aren't finding shines... you just need to completely change your strategy.
If you want Shinys, this is a game of encounters. If the community day rate is 1 / 25 - then it follows you want to try and encounter 25 x Y - where Y equals the number of Shinies you want.
But assuming you are in a city --- You need to move fast and encounter as many Beldums as you can. Parks, high density Pokestop areas, etc. Fire up incense, team up and use a vehicle, etc. You goal shouldn't be to catch anything besides except shinies until you're satisfied with Shinies you have or you know for sure you have a second to catch that Beldum. But time spent catching non-shinies = time spent not finding shinies.
I get for rural players it could be a lot rougher, I'd probably lure up pokestops and use incense to try and get as many spawns by me as possible.
I caught 5 shiny in an hour and called it a morning.
