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JMac Customs 1913 Folding Mech FM-SM-1913 Condition: New, Color: Black, 10% Off w/ Free Shipping

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JMac Customs 1913 Folding Mech, FM-SM-1913
JMac Customs 1913 Folding Mech, FM-SM-1913
JMac Customs 1913 Folding Mech, Black, FM-SM-1913
JMac Customs 1913 Folding Mech, FM-SM-1913
JMac Customs 1913 Folding Mech, FM-SM-1913
JMac Customs 1913 Folding Mech, FM-SM-1913
JMac Customs 1913 Folding Mech, FM-SM-1913
JMac Customs 1913 Folding Mech, FM-SM-1913
JMac Customs 1913 Folding Mech, FM-SM-1913
JMac Customs 1913 Folding Mech, FM-SM-1913
JMac Customs 1913 Folding Mech, FM-SM-1913
JMac Customs 1913 Folding Mech, FM-SM-1913
JMac Customs 1913 Folding Mech, FM-SM-1913
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JMac Customs - NEW 1913 folding mech!
JMac Customs 1913 Folding Mech, FM-SM-1913
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JMac Customs 1913 Folding Mech, FM-SM-1913
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JMac Customs 1913 Folding Mech, FM-SM-1913

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Questions & Answers
Customer Reviews
Helpful Positive Review
Ignore the 1 Star Review by Nick, January 21, 2024
The guy leaving the 1 star review either has no arms or fingers with the strength of a wet noodle. This folding mechanism works perfect on my AP5. A simple lift near the folding mechanism releases it and allows me to fold my stock. There is zero slop...
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3/4 found this helpful
Helpful Negative Review
hard to unlock by maiti, September 1, 2025
Based on mixed good and bad reviews, I believe there is some tolerence/ machining issue goig on here. I unfortunately received a folding mech that just would not move, same experience as one of the reviewer has mentioned. Only way for me to open th...
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2/2 found this helpful
Most Recent Reviews
avoid this product by J, Verified Owner, April 21, 2026
Does not function as intended. I own several folding stocks/braces from other brands, like A3, Sig, Strike Industries and Midwest Industries that all work fine. This one does not, now my Jmac folding stock is a fixed stock. Don't waste your time or m...
Read More...
Most Recent Reviews
absolute trash by shublar, Verified Owner, October 17, 2023
I had to use a rubber mallet and screwdriver to get it to articulate. I'm not sure why they put a 90lb spring in the action. It actually broke my custom made, high then wooden stock trying to move it. If you want a fixed stock that doesn't actuall...
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2/12 found this helpful
Most Recent Reviews
Quality Control Varies Wildly by jasmi, December 25, 2025
Mine was way too stiff. Like another reviewer, I had to use a table and my body weight to open it back up. JMac is fully aware of the issue. But instead of correcting it, they uploaded a Rob Solomon video on their YouTube channel entitled "How to Fo...
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Most Recent Reviews
Jmac 1913 folding stock adapter by Rydog, Verified Owner, May 17, 2025
Solid folding mechanism - will allow jmac or sig styled stocks to attach to it.
Read All 9 Reviews
Condition:
New
Color:
Black

Code: 4VI-STA-JFM19-FM-SM-1913

MPN: FM-SM-1913

List: $149.95Save 10%
$134.96

Product Info for JMac Customs 1913 Folding Mech

Finally our own 1913 folding mechanism! Clamps on any "1913" or "Picatiny" RailWorks with all of our ArmBar, Skeleton Stocks and Skeleton TubesWorks with SIG MPX/MCX folding braces/stocksFolds Left or Rightimage

Specifications for JMac Customs 1913 Folding Mech:

Manufacturer: JMac Customs
Condition: New
Color: Black
Fabric/Material: 4140 heat treated steel
Weight: 4.5 oz

Features of JMac Customs 1913 Folding Mech

  • Folding mech to mount stocks/braces to our infinity mount 3 mounting holes locks deployed and folded

Package Contents:

  • JMac Customs 1913 Folding Mech

JMac Customs 1913 Folding Mech Orderable Models

List of Orderable Models

  • JMac Customs 1913 Folding Mech, Black, FM-SM-1913 , MPN: FM-SM-1913 , Code: 4VI-STA-JFM19-FM-SM-1913

JMac Customs 1913 Folding Mech Unavailable & Discontinued Models

List of Unorderable Models

  • USED, JMac Customs 1913 Folding Mech, Black, FM-SM-1913 , MPN: FM-SM-1913-EDEMO , Code: 4VI-STA-JFM19-FM-SM-1913-EDEMO-RE-C
  • USED JMac Customs 1913 Folding Mech, Black, FM-SM-1913, EDEMO2, Used, Condition Fair , MPN: FM-SM-1913-EDEMO2 , Code: 4VI-STA-JFM19-FM-SM-1913-EDEMO2
  • USED JMac Customs 1913 Folding Mech, Black, FM-SM-1913, EDEMO3, Used, Condition Like New , MPN: FM-SM-1913-EDEMO3 , Code: 4VI-STA-JFM19-FM-SM-1913-EDEMO3
  • USED JMac Customs 1913 Folding Mech, Black, FM-SM-1913, EDEMO1, Used, Condition Fair , MPN: FM-SM-1913-EDEMO1 , Code: 4VI-STA-JFM19-FM-SM-1913-EDEMO1
  • USED, JMac Customs 1913 Folding Mech, Black, FM-SM-1913 , MPN: FM-SM-1913-EDEMO , Code: 4VI-STA-JFM19-FM-SM-1913-EDEMO-RE-B
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