The Amalgamated Society of Core Makers of Great Britain and Ireland (ASC) was a trade union representing foundry workers in the United Kingdom.
About half the members came from the Manchester and District Coremakers' Society, the largest of the local unions.
The union focused on paying benefits to members who were not working, and avoided industrial action.
[1] In 1906, the union was a founder of the Federation of Moulders and Collateral Trades, although this soon collapsed.
It continued alone until 1920, growing to over 4,000 members, when it merged with the Associated Iron Moulders of Scotland and the Friendly Society of Ironfounders to form the National Union of Foundry Workers.