Weird H335 Powder

3rd Iteration
I pulled sample bullets from recently loaded ammo using Starline Brass in 22 ARC and 6.5 Grendel calibers. I measured the powder weights originally loaded vs what weight the ammo currently has. They all weighed identical for both then and now. However, I did find the condition of a batch of 22 ARC ammo to be abnormal. When I attempted to dump the Accurate 2460 powder from one of those cases, not all the powder would pour freely from it. I had to use a toothpick to loosen it, and I felt a small amount of resistance before the powder flowed out of the case. There were a few small lumps of dry, crusty looking powder within the amount which was deposited into the powder measuring pan. The weight was the same as originally loaded, and the clumps disintegrated back into normal looking powder when touched with the toothpick.
I took that powder out to my charcoal BBQ grill and burnt it. It burned perfectly normally. I decided to keep the rest of that ammo loaded, and will closely monitor it when I go to the range to test it (24rounds). Ammo was a mid-range powder load for fire forming new cases (my usual practice).
I had additional new, unloaded Starline brass in 22 ARC, 6.5 Grendel, and 6.5 Creedmoor calibers (luckily, they don't make 6.5 PRC Brass, as I probably would have had some of that too). I gave them all a Walnut media dry bath, 50 cases per batch, for 30 minutes each in my vibratory tumbler. That should eliminate whatever contamination might be inside them. Hopefully, this will end my troubles with "Weird Powder"!
 
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I had some problems with a new batch of H335 a while back. A load well within reloading manual parameters gave unusually high velocities and pressure signs in some .223 loads with 64 grain bullets. I stopped after shooting and chronographing 2 or 3 and pulled the remainder. I haven't gotten back around to working with it yet. I just attributed it to a variation in powder batches. I did not observe any odd material when I pulled the loaded rounds down.
 
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