I thought about the Mexican thing. Then I remembered I had a load for a 44XL w/ red dot.
So I looked up red dot cartridge loads and all the 220 ish grain loads for pistol/ carbine shooting. Most use 5-6.5 grains. But all were less than 1000 fps.
So I'd guess there is either a leading or pressure problem in the 44xl loads above 1000fps w/ red dot.
Long way round is to send $10.00 to someone here that reloads .410 and have them send in the samples for you to Armbrust.
Lots of CAS shooters use the little red dot loads 'cause they're cheap.
