Shared by Archaic Arms in "Catch this" section.
http://av.zrc-sazu.si/pdf/62/AV_62_2011_Laharnar.pdf
More bullets ( a few sites in Slovenia) and almost identical weights.

I have read about Roman lead sling bullets in the range of 20 to 180 gram, with an estimated most likely weight of around 50 grams , with a tendency towards higher weights over the course of time

TOMBELAINE wrote on Jan 31^st, 2023 at 11:32am:

It's funny because It's very likely the opposite was true. With a long sling, you will get maximum velocity with the lighter projectiles, which provides greater range and flatter trajectory at lower angles. At long range, hit probability is also less, so lighter bullets mean you can necessarily carry more of them. 
Heavier bullets on the other hand, are more accurate to use and can be used more effectively with shorter slings for closer ranges. it's intuitive that a heavy bullet is best used when hit probability is higher, which is usually at closer ranges.

I don't know if these archeologists are right or wrong.
Their arguments are based on the analysis of a battle during an excavation. During the attack on a fort, small bullets were found at the location of the attack, and large bullets in front of the second door as a bombardment shot. Soldiers could contribute their military expertise.