I just sent Alliant an email for verification. Supposedly, the Blue MZ pellets by Alliant are NOT discontinued.
I just switched to Blue MZ pellets in December.... for a 2018 trial/testing period. So far - so good. Less residue in the bore afterwards than with Blackhorn. What's lacking is increased bullet speeds that Blackhorn brings (per equal volume used).
Less speed is fine with me. I quit using magnum-type powder loads four years ago. Content with two pellets - that reach 150 yard harvests for me. Content with noticeably less recoil and no hassles keeping breechplugs clean on range visit days.
The #1 thing I'll watch using Blue MZ pellets in 2018, is how it reacts to Michigan's Great Lakes humidity levels. How will the humidity affect ignition of those pellets. That will determine for me if the blue pellets are a keeper, or a goner in 2019.
https://www.americanhunter.org/artic...-muzzleloader/