S/A, F/A. enhanced bolt?
- Thread starter Antoine22
- Start date
If you're talking about AR-15 type files, full auto or M16 bolt carriers are designed to trip the auto sear as it moves into the fully forward position. The part of the carrier that trips the auto sear is typically machined away on semiauto bolt carriers.
This should explain the difference between AR-15 and M16 parts:
www.ar15.com/content/legal/AR15-M16Parts/
I'm not sure what the enhanced bolt is, though.
This should explain the difference between AR-15 and M16 parts:
www.ar15.com/content/legal/AR15-M16Parts/
I'm not sure what the enhanced bolt is, though.
anyone fill in what I missed.
half circle bolt carrier - rear of carrier's lower half machined off to prevent tripping of an Auto-Sear.
Semi-auto bolt carrier (AKA full circle bolt carrier) - rear part mentioned above is machined to prevent tripping an auto-sear, but not completely - leaves part of the rear and allows for a full circle.
Full auto bolt carrier - none of the a/m part is machined away. it is capable of tripping a auto sear. not illegal to own or use in both USA and Canada.
pro's - FA BCG is original weight for a BCG. IF YOU ARE FIRING A FA GUN, This is a must for proper functioning. If you are shooting a semi-auto with 5 rd mags....not needed...nice to have.
semi-auto work's fine also for SA. I would choose this or FA for one reason ONLY! the half-circle BCG, has been thought to lead to possible irregular wear as there is no "bottom" which acts as a "bearing" surface as the bolt carrier cycles within the receiver extension. this is not an issue with a full circle or FA BCG.
Enhanced Carriers - mods done to improve upon the MILSPEC. LMT makes one that has an extra gas vent port in the scallop on the right side. There is also a raised surface at the front of the BCG.
Enhanced Bolts - can be a variation of things...come ones include dual extractor springs and lobster tail extractors, chromed finish (only aides in cleaning), heavy extractor springs, stiffer extractor spring buffers, various different machining methods around the bolt lugs and one piece gas rings.
Hope this helps
Boltgun
half circle bolt carrier - rear of carrier's lower half machined off to prevent tripping of an Auto-Sear.
Semi-auto bolt carrier (AKA full circle bolt carrier) - rear part mentioned above is machined to prevent tripping an auto-sear, but not completely - leaves part of the rear and allows for a full circle.
Full auto bolt carrier - none of the a/m part is machined away. it is capable of tripping a auto sear. not illegal to own or use in both USA and Canada.
pro's - FA BCG is original weight for a BCG. IF YOU ARE FIRING A FA GUN, This is a must for proper functioning. If you are shooting a semi-auto with 5 rd mags....not needed...nice to have.
semi-auto work's fine also for SA. I would choose this or FA for one reason ONLY! the half-circle BCG, has been thought to lead to possible irregular wear as there is no "bottom" which acts as a "bearing" surface as the bolt carrier cycles within the receiver extension. this is not an issue with a full circle or FA BCG.
Enhanced Carriers - mods done to improve upon the MILSPEC. LMT makes one that has an extra gas vent port in the scallop on the right side. There is also a raised surface at the front of the BCG.
Enhanced Bolts - can be a variation of things...come ones include dual extractor springs and lobster tail extractors, chromed finish (only aides in cleaning), heavy extractor springs, stiffer extractor spring buffers, various different machining methods around the bolt lugs and one piece gas rings.
Hope this helps
Boltgun
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looks like boltgun wraped this one up ...
Additionally to what has been posted, the full circle & FA bolts have more mass and thus increase lock time. If you are shooting hotter loads, the increase in lock time can reduce stress on, and increase the life of brass. Could be important for those that shoot heavier rounds (75gr. and up), and handload.
As was said already plus some:
"M16 Bolt Carrier
The M16 bolt carrier serves two functions. The first is that the firing pin is fully shrouded so that the hammer is cocked by the carrier and not the firing pin itself. The second is that the M16 bolt carrier is heavier and therefore increases "lock time" (or the amount of time that the empty case after the primer is struck by the firing pin) which aids in extraction. The heavier carrier also reduces the felt recoil impulse which in turn reduces wear and tear on the other internal parts of the carbine."
"M16 Bolt Carrier
The M16 bolt carrier serves two functions. The first is that the firing pin is fully shrouded so that the hammer is cocked by the carrier and not the firing pin itself. The second is that the M16 bolt carrier is heavier and therefore increases "lock time" (or the amount of time that the empty case after the primer is struck by the firing pin) which aids in extraction. The heavier carrier also reduces the felt recoil impulse which in turn reduces wear and tear on the other internal parts of the carbine."
Some of the Bolt carriers are marketed as "enhanced" (RRA?) just becuase they keep the firing pin shroud.
Regardless, the only REALLY enhanced carriers are made by LMT. That thing is designed for 14.5" barrel and appears to be not so compatible with anything else - some pepole like Ares defence also market "enhanced" BCG. On the other hand, I am not sure about Ares Defence can actually make any operational stuff......
On the other hand, there are two enhanced bolts outthere - LMT and KAC. The LMT one seems to be spotty in performance and quality. The KAC one - it needs its own barrel extension so it is irrelevant.
Anyways, stay away from them, just stick with the regular stuff.
Regardless, the only REALLY enhanced carriers are made by LMT. That thing is designed for 14.5" barrel and appears to be not so compatible with anything else - some pepole like Ares defence also market "enhanced" BCG. On the other hand, I am not sure about Ares Defence can actually make any operational stuff......
On the other hand, there are two enhanced bolts outthere - LMT and KAC. The LMT one seems to be spotty in performance and quality. The KAC one - it needs its own barrel extension so it is irrelevant.
Anyways, stay away from them, just stick with the regular stuff.
Has anyone mentioned another reason for the M16 BCG? On a short barrelled AR, the extra lock time enhances reliability of the rifle. That heavy carrier is one of the ways that the real shorties can be made reliable.
