Sierra is very good about answering questions for anyone, even if it's not about their bullets. You might give them a call or email.
ph: 800-223-8799
email:
[email protected]
The following is from the Hodgon website (
http://www.hodgdon.com/data/rifle/223rem.php):
80 GR. SIE MK
COL: 2.550"
VARGET 25.0 2869 51,500 CUP
BL-C(2) 25.5 2768 49,400 CUP
H335 22.5 2744 50,000 CUP
H4895 24.0 2825 50,000 CUP
H322 22.0 2744 49,000 CUP