The LT-20 should work reliably with any 2 3/4" ammo you feed it. The problem with the 11-87's is they are primarily set up for 3" Magnum loads, so shooting the light loads does not generate high enough port pressure. The valve business for relieving excess presure works, but does not do much for the pressure from a light load. It works better than the 1100 Magnums would do with 2 3/4 inch shells, but is still not perfect. The Trap and Skeet versions of the 11-87's don't have the excess pressure valve, acknowledging they need all the pressure the target shell generates for reliable action.