The Critical bolts are known for being quite a tight fit, which may explain the slow cycle despite the slightly higher than recommended LPR pressure. Might be worth getting a handful of each type of o-ring on the bolt and bolt pin, and switching o-rings until you find a combination that allows the bolt to move easily, but without leaking.
For air to be leaking down the barrel - when the bolt is at rest presumably? - it suggests that either the front bolt pin o-ring or the front bolt o-ring are leaking.
Last edited by Uziel Gal : 04-18-2011 at 12:00 PM.