In that case:
Sanzo's bullet = a slight dent in an Orbital frame but it will push a frame back by about a foot or a few meters depending on how big the damn thing is*. Kinda like the Gaunlet program except a little weaker.
* There
are giant sized Orbital frames. Example:
ZakatGoyjo's Shakujou = make a sharp dent(if hit normally, ie: large surface areas) or do some damage at critical points(Every OF has different critical points, but it's usually the cockpit for larger than normal OFs(see Zakat)).
Hakkai = Same as Gaunlet + a little more damage.
See, Metatro can be damaged more with energy based attacks than with normal attacks. So. . . Yeah.