Poliwag, Butterfree, Beedrill, Onix, Mawile and Gastrodon i've all found usable in OU. Not so much Poliwag (Belly Drum Salac Berry)... But the others work out well. Butterfree rapes non Blissey or Skarmory walls.
???
252 Modest Butterfree Bug Buzz vs Hippowdon: 36.90% - 43.33%
vs Milotic: 24.87% - 29.44%
Psychic vs Tentacruel: 28.02% - 32.69% <--- Not even a 4-hit KO with leftovers and super-effective on the average...
Beedrill has Choice Scarf as to rape weaviles with U-Turn.
Why would Weaviles switch into a Beedrill when Weavile is weak to bug?
Choice Band Onix can sort of hit slow things hard.
Choice Band Onix Earthquake vs Hippowdon: 22.14% - 25.95%
vs Swampert: 27.48% - 32.43%
vs Roserade: 80.46% - 95.02%
BTW: Roserade has less defenses than Weavile. So earthquake won't kill Weavile either.
Mawile can beat most physical dragons one on one with Intimidate, Shucca Berry, Ice Fang, and Sucker Punch.
Intimidated Garchomp Earthquake vs Mawile: 105.39% - 124.07%
Ice Fang Mawile vs Garchomp: 69.75% - 82.07%
With Shucca Berry, Mawile is 2-hit KOed by Garchomp. I admit sucker punch on garchomp might kill... But a choice band on Garchomp w/o intimidate means Mawile is OHKOed even with Shucca berry. W/o Intimidate: 257.26% - 302.49%. With intimidate, 172.20% - 202.49%, which gives Garchomp a chance to OHKO even after getting intimidated by Mawile.
Intimidated Salamence Earthquake vs Mawile: 79.25% - 92.95%
With a Shucca Berry or not, Mawile is 2-hit KOed by Salamence.
Intimidated Mawile Ice Fang vs Salamence: 58.31% - 68.58%
Intimidated Mawile Sucker Punch vs Salamence: 17.82% - 20.85%
Salamence always wins.
In addition, both pokemon commonly use a fire move to deal with Skarmory. Both Salamence and Garchomp OHKO Mawile with Fire Blast (for Skarm). Salamence can OHKO with Flamethrower.
So it isn't just "pure physical" dragons, but "pure physical" dragons that would have been walled by the likes of Skarmory anyway.