You may have wiped a lobe and or lifter, then. It's all over the internet everywhere about Comp's piss poor quality these days. I wouldn't use one of their cams or any of their lifters in a Briggs and Stratton. I hope you figure it out and it's something stupid easy.
I bought a solid roller cam from them last year and within 30 passes it was wiped out along with the new Bam lifters. Plus now everything needs to be gone through.