If thats a magnum barrel you picked up for it, it's probably not going to cycle any low brass or trap loads. The magnum barrels only have one gas port, the regular barrels have 2 gas ports. The idea is because the magnum loads create more pressure, only one gas port is needed to cycle the action without really hammering it. Sometimes they will cycle a heavier trapload, but rarely. If you're plan to shoot a lot of trap, or low brass loads, you're going to have to look for a 2 3/4 inch chambered barrel that has the 2 gas ports.
Optionally, you could use the slug barrel for trap loads, if it's a 2 3/4 inch chamber, then it has the dual gas ports, and will cycle the traploads just fine, however, the smoothbore slug barrel has an improved cylinder choke, which wouldn't be very conducive to trap shooting