Sent you a PM, Panzer but will say very briefly, (Going to plant potatoes before it gets too hot, in 90's here!)
I found it hard to compress and make gas tight. as in the gun 'fluffed" when fired compared to most other materials.
It seemed to me wool is springy, and had to get compacted.
It kay be me doing it wrong!
I found that paper, rolled ina ball and rammed down, Spanish moss from trees, green ivy leaves in V dry weather, felt wads cut with a punch, card wads ditto, all outdid wool wadding.
In the old book "An Essay on Shooting" (1789 I Think!) it says regarding wadding, "....wool is nothing worth".
I also found tow hard to compress, but tow from an old saddle is much more compacted and might work, but never had a saddle to try it!
This was with shot, not a ball.
All best,
Richard.