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Posted: 1/19/2009 5:11:55 PM EDT
| I was going to pick up a new bolt (BCG) and I've seen a few that the end of the firing pin is exposed like it's unshrouded.. Does this really make a difference than one where the firing pin end is more shrouded.. I'll try to come up with some pictures to help show what I'm talking about if I'm not making sence... |
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It is the Colt SP1 design. When an unshrouded carrier is used with a hammer with the little notch on the top it prevents a slamfire from disconnector failure. If the disconnector does not hook the hammer when the carrier presses it down as the carrier recoils into the stock it will lock up when the carrier moves forward. When the carrier moves forward the exposed firing pin head locks on the notch in the top of the hammer and will not close to chamber a round.
On the other hand if a shrouded carrier and round top style hammer is used nothing will catch if the disconnector fails and the bolt carrier will close on the live round. This leaves the potential for a slam fire and an unsafe automatic gun if it happens repeatedly. This can lead to firing out of battery if the round fires before the bolt rotates into the barrel. So in short: An unshrouded carrier is a safety feature that will prevent slamfires when used with a notched hammer. It makes the whole action a little rougher as the parts drag on each other during recoil and charging. It is also much more harsh on the firing pin head as it is dragged across depressing the notched hammer each time the weapon cycles. |
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