Hello all. I have a few 9mm snap-caps. Im not too sure how old they are or how many times theyve been used. Generally, do snap caps last forever or do they wear out? The snap-caps I have are a transparent red with a small spring inside, not sure what brand. Is there a way to test a snap-cap? Never had to really use snap-caps till I got my XD9; dont want to prematuraly break the roll pin. Thanks guys.