A shorter 2.5” shell gives the shooter a tad more room to avoid catching the extractors when loading. When ejecting the the empty hulls it’s more how well the extractors grab the rim the hull and if the right extractor rotates down enough to release the hull. Ejecting the first round is normally never a problem because the shell coming up pushes the first empty out with force, it’s normally the last round that will hang up. The edge of the rim on some shells have more of an angle then others and the extractors don’t grab them as well plus it depends on how much material has been removed from the extractors and extractor spring pressure. I have owned 87’s that will extract and eject any different brand shell I put in them and others that will only work with 2 or 3 different brands, And don’t make love to the gun when you run the lever, especially the last round. My best luck has been with Winchester LNLR, Remington Gun Club, Remington STS and Federal Top Gun Metro hulls. Expecting a gun straight from the factory to eject the last round reliably without any work on the extractors by someone who knows what they are doing is a crap shoot but then some extractors have too much metal removed or not enough or spring pressure isn’t correct or the right extractor doesn’t rotate down enough after they have been worked on too.