Unique...pressure spikes...ringed chambers? Color me skeptical. Unique was invented for greatly reduced loads in straight wall BP cartridges in 1890...and been in continuous production since. A 130 year track record. In every case I have heard of damaged rifles with Unique, people ignored published data and used case fillers. 40 years and counting, I have used Unique with great success in .32-40, .38-55, .44-77 and of course .45-70.
