Not sure where to post this but I’ll just outline whats happening (this is a blueprint project):
I set up a Custom object channel for my projectiles (called Projectiles, gasp) and had the default set to ignore. I went to the couple actors that were going to interact with bullets (the bullets were this new object type) and went into collision, switched it to custom, and ticked “block”. Everything worked fine, On Hit events triggered and destroyed bullets on contact.
However, when I switched several environment components to instanced static meshes for cost, the same settings that worked before quit on me. I had the same exact settings for an actor that had a static mesh and the ISMs and the regular mesh actor worked fine, hits generated. Bullets flew right through the ISMs (CCD has always been on for the bullets). BUT when I switch the Collision Presets in the ISM actor from Custom to Block All and set the default response of the Projectiles objects to block, it works.
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