In addition to all the good points brought up by 'parashooter' and 'whig', your Brass, stamped "WRA Co. - .30 ARMY", is very old and likely has gotten brittle with age, (unless the necks have been annealed).
Personally, I don't risk reloading brass from the 1930's & 1940's. (I'm Scottish, but, new .30-40 brass is available. Using brass older than me seems like false economy).
When I recently made 'reduced' .30-40 loads with the 110 grain RN projectiles, I noticed a bit more resistance to the bullet base entering the case-mouth, then I find with the heavier projectiles, I normally use. (The brass used in my 110 grain 'reduced loads' was trimmed, de-burred, and pretty 'fresh').
Possibly, with 'stiffer' old brass, this resistance may have contributed to your partial case collapse.
I imagine 'flaring' the case mouth a bit would help the flat based 110 grain projectiles more easily enter old case necks. Annealing, trimming, de-burring, and having the 'crimp' out-of-play should eliminate other potential bullet seating issues.
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