You should be able to change your O/U from having ejector to extractor, the spring for doing this should be in the forearm. You can either replace those springs with weaker ones, or just remove them completely.
People who do a lot of trap shooting sometime do this because they don't want to miss catching the shells and have them fly off, they want to save them for reloading; or in a particular case for Browning Citori 725, their ejector rod aren't pinned correctly and after repeated ejections from high volume shooting (which trap shooters tend to do), can fly off. So folks replace the factor ejector spring with a 1911 hammer spring and convert it into extractor.
This is for Browning Citori but it might work in similar fashion on your shotgun:
https://www.shotgunworld.com/threads/ej ... cs.145108/