Dwayne, this is supremely rugged and perfectly recoil-proof, they come with an engraved/laser etched reticle that will be able to withstand extreme forces and will not break shift or snap even if the riflescope is used with heavy calibers. You can use 20 gauge with no issues. Have a great day!

Yes Konus is a well made, durable and affordable, this should handle 20GA recoil no issues, plus Konus from what I've read has excellent warranty and service so if something did go
wrоng
they'll make it right.

Dwayne, yes Sir, this is rated for up to 12 gauge recoil and will have no issue on a 20 gauge shotgun. Cheers and stay safe!

This is one hundred percent waterproof, fogproof and shockproof. Nitrogen charged. Multi coated optics. Engraved 30/30 reticle. Heavy caliber recoil proof reticle. This is heavy caliber recoil proof so should have no issue. Plus it's also rated for airguns Wich sounds weird but airguns do more damage to scopes than most hard hitting calibers. So this will be just fine, hope this helps.