Peter is spot on, an Arrieta is too sweet for this, best, Mike p.s. AYA make barrels for Arrieta, AYA will make you a spare pair of double rifle barrels for a 20 bore in a variety of not too intense cartridges (whether they will do this for a 28 bore I don't know). I considered buying a pair of barrels in .44 Rem Mag for the 20 bore AYA No.1 I bought last year.(all the rifle barrels are brought in from Austria or Belgium) Extrapolating from the above I guess Arietta might be able to supply you with a pair of regulated barrels if you sent them the gun ??