Editing Open bolt (section)

==Other characteristics==
{{Unreferenced section|date=August 2021}}
[[File:Simpified schematic of blowback mechanism with advanced primer ignition.png|thumb|right|Schematic of an Advanced Primer Ignition blowback operation that works by striking the cartridge as its moving forward before it is fully chambered. The forward inertia of the bolt and firing from an open bolt position enables handling of higher pressure ammunition, although it requires the use of rebated rim cartridges]]

An open-bolt weapon will typically have a higher rate of automatic fire than a comparable closed-bolt weapon as the bolt simply needs to return forwards in order for the weapon to fire again, while a closed-bolt design has the additional step of the hammer striking the firing pin.<ref>{{Cite web |date=July 14, 2017 |title=Open Bolt Vs Closed Bolt Firearms |url=https://www.abbeysupply.com/resources/open-bolt-vs-closed-bolt-firearms |url-status=live |access-date=May 13, 2023 |website=Abbey|archiveurl=https://web.archive.org/web/20230513151501/https://www.abbeysupply.com/resources/open-bolt-vs-closed-bolt-firearms|archive-date=May 13, 2023}}</ref> Having a higher fire rate can be both an advantage and disadvantage depending on the situation. For handheld weapons, typically a lower rate of fire is desirable, as this will conserve ammunition and help keep the level of recoil more manageable. For vehicle-mounted weapons or fixed emplacements, however, a higher rate of fire is often desirable. In these situations, ammunition and recoil are less of a concern and the higher rate of fire will increase the likelihood of a round hitting the target, particularly when employed against fast-moving targets such as aircraft.

Many movies and video games portray open-bolt weapons as needing to be cycled after reloading. This is not generally true, however, as open-bolt weapons send the bolt carrier back into a cocked position via the excess gas after the last round is fired. The exception to this is if the weapon is fully automatic and the trigger is held down after the last round was fired (and the gun does not have a "last round bolt hold open" mechanism) at which point the bolt will fly forward once more and stay there. In this case, the bolt merely needs to be retracted to the rearward position and does not return forward as is sometimes portrayed.

Another feature of open-bolt designs is that the magazine simply needs to be removed to completely unload the weapon. A closed bolt requires the second step of cycling the action to remove the last round in the chamber (unless the weapon features an automatic hold-open device). It is essential to remove a loaded magazine before performing maintenance, or trying to cycle or close the bolt (as is often done to keep the weapon clean when not in use). If one were to close the bolt (say by pulling the trigger and riding the bolt to the closed position), as soon as the bolt closes it will fire if a loaded magazine was left in the gun. This may be true with weapons utilizing a [[Primer (firearm)|striker]], but not with a weapon using a fixed [[firing pin]], which relies on the momentum of the bolt to impart the energy to ignite the [[Primer (firearm)|primer]]. This is a common feature in basic [[submachine gun]]s like the [[Sten gun]] or [[M3 submachine gun|M3 "Grease Gun"]], and even some [[machine gun]]s. With a fixed firing pin, when the bolt is closed gently, without the momentum of the bolt closing at normal speed, there is not enough force imparted to the firing pin to ignite the primer. In this circumstance there will be a round in the chamber and a firing pin pressing on it with some force, but not enough to ignite the primer, which requires a sharp, focused impact. However, the weapon would be at risk of firing if dropped, much like the danger of loading [[spitzer bullet]]s into a weapon with a [[tube magazine]]. A related issue is that the safety of an open-bolt weapon must be designed to lock the bolt in the rearward position. Often safeties only block the movement of the trigger, so, as explained above, if the weapon is dropped or if the sear becomes worn, the bolt can slam home, firing the weapon (although this issue is true to a degree in closed-bolt firearms as well).