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Gas Block Combo With Detent Hole
Gas Block Combo With Detent Hole
Gas Block Combo With Detent Hole
Gas Block Combo With Detent Hole
Gas Block Combo With Detent Hole
Gas Block Combo With Detent Hole
Gas Block Combo With Detent Hole
Gas Block Combo With Detent Hole
Gas Block Combo With Detent Hole
Gas Block Combo With Detent Hole
Gas Block Combo With Detent Hole
Gas Block Combo With Detent Hole
Gas Block Combo With Detent Hole
Gas Block Combo With Detent Hole
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JMAC CUSTOMS LLC - Gas Block Combo With Detent Hole

1 Review
Gas Block Combo With Detent Hole
Brownells #
100800074
MFR #
GBC-13-W
UPC
$107.96
Coupon Code
Purchase Limit Help

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Standard Shipping Estimated Delivery
Estimated delivery: Oct 2
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International purchase information

Specifications
Gas Block Style:
Screws
Color:
Black
Gas Block Diameter:
0.750 Inches
Model Number:
Fixed
Material:
Steel
Quantity:
1
Restriction
Gun Part Restrictions:
Yes
View US State Restrictions
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International purchase information

What is the JMAC CUSTOMS LLC - Gas Block Combo With Detent Hole?

Gas Block Combo

  • 13 Collab with Sabrewerks13
  • With detent hole
  • This HAS a detent hole in the front

GBC-13 is a copy of the East German 74nk Front Sight Gas Block Combo

  • Perfect for Pistol, SBR, and Rifle builds to lighten up the front end and give it a custom look
  • Fits common 0.591"" gas block barrel journals
  • Has 90* gas port and is a direct replacement for most 90* gas blocks, will work on 45* gas ports with minor gun-smithing
  • Uses standard front sight windage drum and pin (available for purchase here – Windage Drum Front Sight Post
  • Available with detent and spring at 12 o'clock location. Accepts standard AKM spring and detent
  • Has built in cleaning rod holder
  • Cast in the US using Wax Casting techniques similar to the modern Russian barrel components
  • Machined in the US
  • 4140 Heat Treated to Rockwell 32C
  • Black Nitrided in the US

JMAC recommends having a Kalashnismith install.

Gun Part Restriction
Gun Parts have restricted shipping to CA.

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GAS BLOCK COMBO WITH DETENT HOLE REVIEWS

5.0
1 Review
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5
Nice conbo block at good price
I'm building an AK-104 from a bulgarian kit with a JMac 14.5" barrel. I wanted a gas block I could tune to specific loads, or suppressor use. This was the best priced adjustable combo block I could find. Fit and finish were great. It'll be a while before I finish out the build. I'll update the review then, but so far it was shipped quick, nice price, and looks great.
Would you recommend this? Yes, I would recommend to a friend
by donald on May 18, 2026
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