What is an ar 15 buffer spring life span (carbine spring) I'm looking into buying spare parts
Buffer spring life is measured in inches: as long as it's between 10 1/16" - 11 ¼" it's G2G.
Typical life in rounds is well into the thousands.
Check out Sprinco for "long life" action and extractor springs.
I'd go ahead and replace mine after 20,000 rounds, but like B6 said, if it's still in spec you can keep using it
2,500 round interval,
Inspect and replace as necessary extractor spring, insert and O-ring
5,000 round interval
Replace extractor spring
Replace extractor insert
Replace Crane O-ring
Replace gas rings
Replace action spring @ 5000 rounds ( or buy chrome molly springs, i.e. Sprinco which last WAY longer)
10,000 round interval
Replace lower receiver parts
15,000 round interval
Awesome info thank you