It seems like you're asking about a "shot chain measurement", but that term is not a standard one in any field that I am aware of. Could you please clarify what you mean by "shot chain measurement"?

To help me understand, could you provide some context or details? For example:

* What is the purpose of this measurement? Is it for surveying, engineering, construction, or something else?

* What is the equipment or method used? Are there any specific tools involved?

* Where did you encounter this term? Is it in a book, article, or other document?

Once I have a better understanding of what you're referring to, I can help you understand the concept.