I stopped using these powders in 350 legend because I had some pressure spikes. The problems I saw were with <80% fill in the case.
I shot a lot of W296 and had 6 cases that the primer fell out of and/or jammed my gun. Couple months later, I am reloading that ONCE fired brass and am seeing primer pockets too loose to take a primer. This brass is all Winchester and all the brass that I am now throwing away was loaded with W296 or AA11FS (H110 is similar).
I am shooting W296 with a very small boolit 125 grain and pretty much filling the case - that shoots well and the cases are OK.