They will fit, but as birdtracker said, some fitting may be required, which should be checked by a professional (legal disclaimer). The other thing you need to be aware of is that the rib is likely a different height than the trap barrel, as a result you may have trouble with the comb height. Bill Malcolm
When trying out a new set of barrels on a Bretta 680 series action, don't force anything. Gently close the barrels to the action and don't slam the forearm on. I've seen both done and getting them apart can be a bit of a booger.
As your Beretta barels wear, the locking pins will become loose. The fix is replacement pins of a larger size. Think there are 4 different sizes. If I bought a used barrel set I would want to check the pin holes to see they were the same. I have a 686 single barrel and a 682 O/U, the barrels fit interchangeably, but one set of pins are the original and the other 2 sizes up; 686 wear. I have yet to shoot the barrels interchangably. Expect I will get the 686 barrel holes welded and re drilled to fit introductory pins and then will interchange the barrels. Hoipe this helps.
Hey 22 Hornet I'm recovering from cataract surgery and just discoverer I can see again. I'm trying to change one of my Trap guns around a little to try on those sporting birds. Wish me luck, or better yet pray for me.