Anyone ever have performance decline after cleaning and lubing slugs?

I have been shooting the .25 29gr. slugs with the the old lube, they shoot great from 965 to 1000 fps. I have shot them straight out of the bag and cleaned and re-lubed them with no difference in accuracy. 

I just received .30 49.5gr slugs they are bright, shiny and ready to shoot out of the bag !

I like the new lube and bright shiny slugs! They stack at 50 yards(as far as I have been able to shoot so far) @ 950fps. 

Another great product from NSA for the FX Impact is the NSA pin probe kit. It is very easy to install and very easy to adjust slug seating depth ! 


 
Unfortunately I have found a few manufacturers of slugs have a lot of lead flakes in their product. I rarely if ever cleaned my barrel when shooting pellets and when I did I NEVER saw any lead fouling. When shooting these uncleaned slugs my barrel gets loaded with these extraneous shinny flakes of lead. Now I am forced to wash, clean then lube most of the slugs I have purchase.