AR Sponsor
Posted: 3/3/2008 2:13:23 AM EDT
|
When is a "F" marked front sight base used? Is it used in conjunction with A3 uppers or only A3 uppers on M4's? Does it work with 20" rifles with A3 uppers? Thanks |
| It works with everything. Some combinations of barrel, upper and rear sight require more elevation adjustment than a normal FSB can provide. The shorter the sight radius the more likely it is to be an issue. In these cases you either need an F marked FSB or an extra tall front sight post. Since you cannot easily replace a FSB, getting a barrel with an F marked part in the first place avoid potential problems. |
AR Sponsor
Win a FREE Membership!
Sign up for the ARFCOM weekly newsletter and be entered to win a free ARFCOM membership. One new winner* is announced every week!
You will receive an email every Friday morning featuring the latest chatter from the hottest topics, breaking news surrounding legislation, as well as exclusive deals only available to ARFCOM email subscribers.