Rim Lock - Revision history

Admin: /* External references */

2026-09-07T05:03:51Z

External references

Admin: /* Mechanical Prevention */

2026-09-07T04:26:04Z

Mechanical Prevention

Admin at 03:53, 7 September 2026

2026-09-07T03:53:30Z

Admin at 03:52, 7 September 2026

2026-09-07T03:52:18Z

Admin at 09:31, 10 May 2026

2026-05-10T09:31:19Z

Admin at 09:30, 10 May 2026

2026-05-10T09:30:50Z

Admin at 09:30, 10 May 2026

2026-05-10T09:30:42Z

Admin at 08:10, 5 November 2019

2019-11-05T08:10:15Z

Admin: Created page with " File:Rim-Lock-Rimlock-Diagram-Illustration-Malfunction-Firearm-Wiki.gif|frame|right|An illustration describing rim lock on rimmed and semi-rimmed firearm cartridges. The le..."

2019-11-05T06:03:24Z

Created page with " File:Rim-Lock-Rimlock-Diagram-Illustration-Malfunction-Firearm-Wiki.gif|frame|right|An illustration describing rim lock on rimmed and semi-rimmed firearm cartridges. The le..."

New page

[[File:Rim-Lock-Rimlock-Diagram-Illustration-Malfunction-Firearm-Wiki.gif|frame|right|An illustration describing rim lock on rimmed and semi-rimmed firearm cartridges. The left side shows proper stacking of rounds, allowing for reliable feeding. The right side shows rim lock, where the rim of the first round has become obstructed by the rim of the following round, causing a jam.]]

'''Rim lock''' (also written as "'''rimlock'''") is a phenomenon that occurs in magazine-fed guns that fire rimmed or semi-rimmed cartridges. Some examples of such cartridges include [[.22 Long Rifle]], [[.22 Magnum]], [[.357 Magnum]] (rimmed) as well as [[.32 ACP]] and [[.38 Super]] (semi-rimmed).

The issue is that in a magazine-fed firearm, particularly when involving a detachable magazine, the top most round in the magazine can sometimes slip backward behind the rim of the next round, causing the gun to seize up and be unable to feed the round from the magazine.

@@ Line 29: / Line 29: @@
 * [[Kel-Tec P32]]
-== External references ==
+== External References & Resources ==
 [https://www.reddit.com/r/MosinNagant/comments/17q17xs/whats_wrong_with_my_m9130/ Reddit thread addressing Mosin-Nagant Rim Lock]

← Older revision		Revision as of 04:26, 7 September 2026
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	* [[Mosin-Nagant]]: Implements an interruptor, a small arm that swings into the magazine when the bolt is open in order to keep the 2nd round pressed downward. From [https://www.reddit.com/r/MosinNagant/comments/17q17xs/whats_wrong_with_my_m9130/ this Reddit thread], many agree that a faulty interruptor is a common cause of feeding failures or double feeds in Mosin-Nagant rifles. Also, improper tension, or being able to catch on the stock when it shouldn't, are common causes of rounds failing to sequence correctly. Users say that simply adjusting or replacing the spring can often fix these issues.		* [[Mosin-Nagant]]: Implements an interruptor, a small arm that swings into the magazine when the bolt is open in order to keep the 2nd round pressed downward. From [https://www.reddit.com/r/MosinNagant/comments/17q17xs/whats_wrong_with_my_m9130/ this Reddit thread], many agree that a faulty interruptor is a common cause of feeding failures or double feeds in Mosin-Nagant rifles. Also, improper tension, or being able to catch on the stock when it shouldn't, are common causes of rounds failing to sequence correctly. Users say that simply adjusting or replacing the spring can often fix these issues.
		+
		+	* Angled magazine & feed lips: Many modern guns chambered in semi-rimmed cartridges, such as the Kel-Tec P32 use precisely shaped magazine & feed lips and such positioning that it tries to make sure a cartridge is always in front of the next, never allowing the next cartridge's rim to hang up the one before it. However, with loads such as shorter hollow points, there is still sufficient space in the magazine for cartridges to move back and forth, allowing potential rim lock. This brings in the idea of a "flyer wire", a DIY magazine mod for such pistols.
		+
		+	* [[Flyer Wire]]: The idea of a flyer wire is to install a steel wire through the rear part of the magazine, such that cartridges are always forced into a forward position and prevented from shifting. If rounds can no longer shift, they can no longer jump over the rim of the next cartridge, preventing rim lock. This mod appears to be named after the user "Flyer" from the Kel-Tec Owner's Group (KTOG) forum, who came up with the idea. It remains a popular and cheap modification for the P32 and similar handguns. There is a guide to installing it into P32 magazines [https://www.1bad69.com/keltec/flyerwire.htm at this link.]
		+
		+	== Other Articles ==
		+
		+	* [[Mosin-Nagant]]
		+	* [[Kel-Tec P32]]
		+
		+	== External references ==
		+
		+	[https://www.reddit.com/r/MosinNagant/comments/17q17xs/whats_wrong_with_my_m9130/ Reddit thread addressing Mosin-Nagant Rim Lock]
		+
		+	[https://www.gunboards.com/threads/how-the-interrupter-works-to-prevent-rim-lock-in-mosins.398305/ Gunboards thread explaining the workings of the Mosin-Nagant's interruptor arm.]
		+
		+	[https://www.1bad69.com/keltec/flyerwire.htm Installing a "Flyer Wire" in a Kel-Tec P32 Magazine]

@@ Line 10: / Line 10: @@
 == Preventing Rim Lock ==
-In most firearms, rim lock is relatively easy to avoid. By taking care to make sure that each round's rim is sitting in front of the previous one, this should eliminate most instances of rim lock. However, it may be the case that some magazines are not designed to properly allow for this but give just enough room for cartridges to lock together and still cause issues. Overall, paying attention during loading will resolve almost all issues of rim lock.
+=== Careful Loading ===
 === Mechanical Prevention ===

← Older revision		Revision as of 03:52, 7 September 2026
Line 10:		Line 10:
	== Preventing Rim Lock ==		== Preventing Rim Lock ==

−	In most firearms, rim lock is relatively easy to avoid. By taking care to make sure that each round's rim is sitting in front of the previous one, this should eliminate most ~~if not all possibility~~ of rim lock. However, it may be the case that some magazines are not designed to properly allow for this but give just enough room for cartridges to lock together and still cause issues. Overall, paying attention during loading will resolve almost all issues of rim lock.	+	In most firearms, rim lock is relatively easy to avoid. By taking care to make sure that each round's rim is sitting in front of the previous one, this should eliminate most instances of rim lock. However, it may be the case that some magazines are not designed to properly allow for this but give just enough room for cartridges to lock together and still cause issues. Overall, paying attention during loading will resolve almost all issues of rim lock.
		+
		+	=== Mechanical Prevention ===
		+
		+	Many designs have implemented some features to address this serious issue.
		+
		+	* [[Mosin-Nagant]]: Implements an interruptor, a small arm that swings into the magazine when the bolt is open in order to keep the 2nd round pressed downward. From [https://www.reddit.com/r/MosinNagant/comments/17q17xs/whats_wrong_with_my_m9130/ this Reddit thread], many agree that a faulty interruptor is a common cause of feeding failures or double feeds in Mosin-Nagant rifles. Also, improper tension, or being able to catch on the stock when it shouldn't, are common causes of rounds failing to sequence correctly. Users say that simply adjusting or replacing the spring can often fix these issues.

@@ Line 4: / Line 4: @@
 '''Rim lock''' (also written as "'''rimlock'''") is an issue that can occur in magazine-fed guns that fire rimmed or semi-rimmed cartridges. Examples of such cartridges include [[.22 Long Rifle]], [[.22 Magnum]], [[.357 Magnum]], [[7.62x54r]] (all rimmed) as well as [[.32 ACP]] and [[.38 Super]] (both semi-rimmed).
-The issue is that in a magazine-fed firearm, particularly when involving a detachable magazine or internal box magazine, the top most round in the magazine can sometimes slip backwards behind the rim of the next round, causing the gun to seize up and be unable to feed the round from the magazine. Alternatively, the user can easily load a round in this way by accident. This is not really an issue in firearms with a tube magazine because the rims have no way of grabbing each other and locking up.
+== What causes rim lock? ==
 == Preventing Rim Lock ==
 In most firearms, rim lock is relatively easy to avoid. By taking care to make sure that each round's rim is sitting in front of the previous one, this should eliminate most if not all possibility of rim lock. However, it may be the case that some magazines are not designed to properly allow for this but give just enough room for cartridges to lock together and still cause issues. Overall, paying attention during loading will resolve almost all issues of rim lock.

← Older revision		Revision as of 09:30, 10 May 2026
Line 2:		Line 2:
	[[File:Rim-Lock-Rimlock-Diagram-Illustration-Malfunction-Firearm-Wiki.gif\|frame\|right\|An illustration describing rim lock on rimmed and semi-rimmed firearm cartridges. The left side shows proper stacking of rounds, allowing for reliable feeding. The right side shows rim lock, where the rim of the first round has become obstructed by the rim of the following round, causing a jam.]]		[[File:Rim-Lock-Rimlock-Diagram-Illustration-Malfunction-Firearm-Wiki.gif\|frame\|right\|An illustration describing rim lock on rimmed and semi-rimmed firearm cartridges. The left side shows proper stacking of rounds, allowing for reliable feeding. The right side shows rim lock, where the rim of the first round has become obstructed by the rim of the following round, causing a jam.]]

−	'''Rim lock''' (also written as "'''rimlock'''") is an issue that can occur in magazine-fed guns that fire rimmed or semi-rimmed cartridges. Examples of such cartridges include [[.22 Long Rifle]], [[.22 Magnum]], [[.357 Magnum]], [[7.62x54r]] (rimmed) as well as [[.32 ACP]] and [[.38 Super]] (semi-rimmed).	+	'''Rim lock''' (also written as "'''rimlock'''") is an issue that can occur in magazine-fed guns that fire rimmed or semi-rimmed cartridges. Examples of such cartridges include [[.22 Long Rifle]], [[.22 Magnum]], [[.357 Magnum]], [[7.62x54r]] (all rimmed) as well as [[.32 ACP]] and [[.38 Super]] (both semi-rimmed).
−
−	The issue is that in a magazine-fed firearm, particularly when involving a detachable magazine or internal box magazine, the top most round in the magazine can sometimes slip backward behind the rim of the next round, causing the gun to seize up and be unable to feed the round from the magazine. Alternatively, the user can easily load a round in this way by accident. This is not really an issue in firearms with a tube magazine because the rims have no way of grabbing each other and locking up.

		+	The issue is that in a magazine-fed firearm, particularly when involving a detachable magazine or internal box magazine, the top most round in the magazine can sometimes slip backwards behind the rim of the next round, causing the gun to seize up and be unable to feed the round from the magazine. Alternatively, the user can easily load a round in this way by accident. This is not really an issue in firearms with a tube magazine because the rims have no way of grabbing each other and locking up.

@@ Line 2: / Line 2: @@
 [[File:Rim-Lock-Rimlock-Diagram-Illustration-Malfunction-Firearm-Wiki.gif|frame|right|An illustration describing rim lock on rimmed and semi-rimmed firearm cartridges. The left side shows proper stacking of rounds, allowing for reliable feeding. The right side shows rim lock, where the rim of the first round has become obstructed by the rim of the following round, causing a jam.]]
-'''Rim lock''' (also written as "'''rimlock'''") is a phenomenon that occurs in magazine-fed guns that fire rimmed or semi-rimmed cartridges. Some examples of such cartridges include [[.22 Long Rifle]], [[.22 Magnum]], [[.357 Magnum]] (rimmed) as well as [[.32 ACP]] and [[.38 Super]] (semi-rimmed).
+'''Rim lock''' (also written as "'''rimlock'''") is an issue that can occur in magazine-fed guns that fire rimmed or semi-rimmed cartridges. Examples of such cartridges include [[.22 Long Rifle]], [[.22 Magnum]], [[.357 Magnum]], [[7.62x54r]] (rimmed) as well as [[.32 ACP]] and [[.38 Super]] (semi-rimmed).
-The issue is that in a magazine-fed firearm, particularly when involving a detachable magazine, the top most round in the magazine can sometimes slip backward behind the rim of the next round, causing the gun to seize up and be unable to feed the round from the magazine.
+The issue is that in a magazine-fed firearm, particularly when involving a detachable magazine or internal box magazine, the top most round in the magazine can sometimes slip backward behind the rim of the next round, causing the gun to seize up and be unable to feed the round from the magazine. Alternatively, the user can easily load a round in this way by accident. This is not really an issue in firearms with a tube magazine because the rims have no way of grabbing each other and locking up.