Looking back over your original post, I see you said the powders appeared to be the same. Looking at the descriptions in Whelen's book and comparing to your photo, the powder is likely WA. The grains of WA were .08" diameter and .04-.05" long. All the MR and IMR powders then were relatively thin, like the more "modern" 4064 and 3031.

One odd thing is the charge weights you have. Whelen said 36.2 gr was already producing 40000 with the 220. The smaller load you have would be closer to 2000 fps from 30" and likely under that speed.

For the 1920's cartridges, the use of WA also seems odd. Whelen considered WA thoroughly obsolete in 1918, being erosive (which Frankford reported back in the 1890s) and rather inflexible with bullet weight.