There are various carp fishing rigs which will allow the lead to drop off once you get a take but like most rigs they are suited to various fishing situations such as a lead clip set up a great method which will enable the lead to pull free should it become snagged but I wouldn’t use one in heavy weed as they can become weed chocked and the clip will not be able to serve its purpose,  or there’s the inline lead set up where by the leader or lead core is ran on the outside of the lead the tail rubber and swivel are used to hold the lead in place until a pick up and the lead is dropped once the swivel is pulled free from the lead a great method but again has limitations to its use.