Now: $145.00
(You save )
(14 reviews) Write a Review


(FSB-24mm) Front sight block with integrated gas block.
Our new combination 24mm FSB/Gas Block is based off of the traditional AK104/105 CR series gas block with M24x1.5 RH Threads . The new FSB-24mm maintains the traditional Russian 105 AK look but with the traditional Bulgarian 104CR 90 gas port location.

  • Gas Block with M24x1.5 RH Threads.
  • Precision machined from 4140 chromoly steel
  • Black Nitride Finish
  • Surface Hardness: 68RC+ 
  • Fits standard AK barrels with 90 deg gas port location & .591 OD barrel journal at gas block location. SAIGA, ARSENAL, AK-47, AK-74 and other AKM mil-spec barrels. .
  • Uses original AK sight parts. (Sight drum & sight post not included)
  • Set comes with plunger pin, plunger pin spring, and retainer pin. 

NOTE: This part is for experienced builders & gunsmiths only! Will only work on a rifle with a barrel diameter of .591” and a 90 degree gas port. Use of 3mm x 10mm Alloy pin recommended for installation. Not for use on SAM7k or Krink pattern barrel, Vepr, Romanian or Yugo guns.


14 Reviews

  • 5
    Perfect fit and great quality

    Published by Ryan on 08/26/2022 07:08:26

    I used this combo fsb for an AK-105 type build I did a while back and it completed the front end perfectly. My only complaint is that MDC doesn’t have any more in stock.

  • 3
    Doesn’t fit

    Published by DOES NOT FIT SAIGA .233 on 03/21/2022 09:03:32

    Build quality is excellent finishes excellent machining is perfect but inside diameter is 30,000’s smaller than a .223 Russian Saiga it says it will fit with a Saiga but it does not MDC: Please check your barrel diameter before purchasing or installing. As per the description, this will only work on a rifle with a barrel diameter of .591” and a 90 degree gas port. The early SAIGA .223 rifles had a larger barrel diameter at the gas block. Please send the block back if it does not fit, and we will refund you.

  • 5
    Combo block

    Published by Cody on 02/16/2022 04:02:55

    Fit and finish is awesome. Only wish their was t a step down on the top (multiple people have mentioned) but it’s not a deal breaker for me when the quality is this good. The 105 is nearing completion now! 10/10 would recommend!

  • 5
    24MM FSB

    Published by Abel Trevino on 02/07/2022 04:02:52

    Great product, good design...I would recommend and purchase again.

  • 5

    Published by Roy on 01/10/2022 09:01:40

    Very well built fsb. Perfect all around. Its high quality shows.

  • 5
    So impressed

    Published by Nicholas Willard on 01/10/2022 08:01:01

    I’m making 12.4” MB74 but with more updated parts and this was absolutely top of the list. The level of quality and affordability is ridiculous in a good sense. I waited a good while for restock but was so excited when I finally saw them back then after a short waiting finally getting to hold and feel it, the detail and quality is just amazing but it also still looks pretty much like a Russian gas block even for someone who’s a stickler for details. I’d recommend this to ANYONE.

  • 3
    Detent pin index location

    Published by Unknown on 02/01/2021 02:02:09

    Overall build quality is solid, finish is nice and machining quality is exelent, however it gets a couple stars off one for having that recessed ring that a legit 105 fsgb doesn't have and causes it to look a little off, and another because the detent pin indexes russian made muzzle devices approximately 2 degrees off from center (only really noticable on the russian manufactured 105 booster)

  • 5
    Real nice combo block...

    Published by NorincoKid on 01/30/2021 05:01:24

    Its nice. Well made, and just looks like its supposed to be on there. I had no issues installing it on a standard AK74 barrel with the gas port pre-drilled. Everything lined up perfectly. Very happy with it. Makes for a great 104CR type rifle.

  • 1
    Does not fit arsenal AK

    Published by Tyler on 12/30/2020 07:12:41

    This gas block is marketed as being able to work with arsenal AKs. It does not work with an arsenal SAM7k without heavily modifying its gas tube. MDC: Tyler the SAM7k is not a standard AKM model. Please consult us or any professional builder before purchasing. Everything is in the description. Feel free to contact us and send it back if it does not work.

  • 5

    Published by PewPewPatriot on 12/18/2020 08:12:04

    Really amazing product...tied together my AK105 Clone perfectly. My only suggestion to MD would be to come together with a network of GunSmiths across the country so there could be a recommended smith to install wherever you are shipping to...AWESOME PRODUCT

  • 5

    Published by Jim on 11/19/2020 12:11:56

    It's about time someone made one of these! The part I received is beautifully machined, and it fit multiple 24mm boosters with no problems. Looking forward to installing this on a Saiga.

  • 4
    Gas block

    Published by Spool on 11/16/2020 09:11:58

    Quality and finish look great, arrived quickly. Only 4 stars because it hasn’t been installed by my builder yet, but I don’t anticipate any issues.

Related Products