Home
Up

Dimensions & Measurements

  • Thread Pitch Sizes
  • Gas Port Sizes
  • Barrel Thread Sizes
  • Journal Sizes
  • FAL Barrel Measurements

 

 

Thread Pitch Sizes

           


 

Most of this information is originally from the AA-OK Tech Info Page and from spot measurements of different barrels.

 

Gas Port Sizes

Caliber Angle Diameter Bit Size Breech Distance
7.62x39 45 degree .177" # 16 bit 11.625" (11 5/8") / 295.275mm
7.62x39 90 degree .177" # 16 bit 11.9063" (11 29/32") / 302.420mm
5.45x39 90 degree .076" # 48 bit 11.9063" (11 29/32") / 302.420mm
5.45x39
AKS-74U
90 degree .070" # 50 bit 7.1305" (~7 1/8") /  181.115mm
5.56x45 Saiga 90 degree .067" # 51 bit 11.9063" (11 29/32") / 302.420mm
5.56x45
Galil
30 degree .073" # 49 bit 11.718" (11 23/32") / 297.658mm
7.62x51
Saiga
90 degree      
7.62x51
Yugo
45 degree      

 

Barrel Thread Sizes - Muzzle

Caliber Size x Pitch
7.62x39  14mm x 1.0 LH Thread
5.45x39  
 
  • Bulgarian AK-74/AKSU FSB: 24mm x 1.5 RH Thread
  • Romanian AK-74 FSB: 22mm
  • Polish Tantal wz.88
5.56x45 Saiga  n/a (threads on FSB)
5.56x45 Galil  13mm x 1.0 RH Thread
Saiga-12   22mm x 0.75 RH Thread

 

Journal Sizes

7.62x39 Caliber

CHINESE AK BARREL:  O. D. DIMENSIONS
Chamber .764" (19.25mm w/ .005 - .006" press fit)
Rear Sight Base .734" (18.5mm w/ .005 - .006" press fit)
Handguard Retainer .691" 
Gas Block .634" (16mm w/ .003 - .006" press fit)
Front Sight Base .594" (15mm w/ .003 - .006" press fit)
   
CHINESE AK BARREL (threaded):
Chamber .903" (22.95mm)
   
EURO AKM PATTERN BARREL:
Chamber .908"  (23mm w/ .003 - .004" press fit)
Rear Sight Base .694" (17.5mm w/ .003 - .004" press fit)
Handguard Retainer .671" 
Gas Block .594" (15mm w/ .003 - .004" press fit)
Front Sight Base .575" (14.5mm w/ .003 - .004" press fit)
   
YUGO M70 PATTERN BARREL:
Chamber .908"  (23mm w/ .003 - .006" press fit)
Rear Sight Base .730" (18.5mm w/ .003 - .006" press fit)
Handguard Retainer .687"8.4375"/ 214.31mm from breech face (8 7/16)
Gas Block .630" (16mm w/ .003 - .006" press fit)
Front Sight Base .593" (15mm w/ .003 - .006" press fit)
   
YUGO M92 PATTERN BARREL:
OAL: 10" (subtract .015" recess at FSB)  254mm
Chamber .907"  (23mm w/ .003 - .004" press fit)Hinge Block
Hinge Block .736" (18.694mm w/ .002 - .004" press fit)
Handguard Retainer .687" 7.375" / 187.3mm from breech face
Front Sight/Gas Block Combo Base .591" (15mm w/ .002 - .004" press fit)
   
ROMANIAN  AKM PATTERN BARREL:
Chamber .908"  (23mm w/ .003 - .006" press fit)
Rear Sight Base .691" (17.57mm w/ .003 - .004" press fit)
Handguard Retainer .668" 8.25" / 209.55mm from breech face (normal)
Gas Block .593" (15.07mm w/ .003 - .004" press fit)
Front Sight Base .573" (14.57mm w/ .003 - .004" press fit)
   
ROMANIAN RPK PATTERN BARREL:
OAL  mm
Chamber .908"  (23mm w/ .003 - .006" press fit)
Rear Sight Base .884" (22.45mm w/ .003 - .004" press fit)
Handguard Retainer  .863" 8.0938" (8 3/32") / 205.58mm from breech face
Cleaning Rod Retainer .756"15.6875" (15 11/16") / 398.46mm from breech face
Gas Block .789" (20mm w/ .003 - .004" press fit)
Front Sight Base/Bipod Base ." (mm w/ .003 - .004" press fit)
   

 

5.45x39 Caliber

AKS-74U BARREL:  O. D. DIMENSIONS
OAL 8.3125" (8 5/16") 211.14mm
Chamber .865"  (22mm w/ .001 - .003" press fit)
Hinge Block  .689" (17.5mm w/ .002 - .003" press fit)
Bottom Handguard Bearing Surface .665"  
Handguard Retainer .608" 6.03" / 153.15mm from breech face
Front Sight/Gas Block Combo Base .551" (14mm w/ .001 - .003" press fit)
 
BULGARIAN AK74 BARREL:
Chamber .871" (22mm w/ .002 - .003" press fit)
Rear Sight Base .694" (17.5mm w/ .003 - .004" press fit)
Handguard Retainer .671" 7.875" / 200.25mm from breech face 
Gas Block .594" (15mm w/ .003 - .004" press fit)
Front Sight Base .575" (14.5mm w/ .003 - .004" press fit)
 
GERMAN AK74 BARREL:
Chamber .867"  (22mm w/ .001 - .002" press fit)
Rear Sight Base .694" (17.5mm w/ .003 - .004" press fit)
Handguard Retainer .671"  
Gas Block .594" (15mm w/ .003 - .004" press fit)
Front Sight Base .575" (14.5mm w/ .003 - .004" press fit)
 
ROMANIAN AK74 BARREL:
Chamber .908" (23mm w/ .003 - .004" press fit)
Rear Sight Base .694" (17.5mm w/ .003 - .004" press fit)
Handguard Retainer .671"  
Gas Block .594"  (15mm w/ .003 - .004" press fit)
Front Sight Base .517" (13mm w/ .004 - .005" press fit)
 
 ROMANIAN SHORT BARREL (AIM):
Chamber .908" (23mm w/ .003 - .004" press fit)
Rear Sight Base .694" (17.5mm w/ .003 - .004" press fit)
Handguard Retainer .671"  
Combo Gas Block & Front Sight Base .575" (14.5mm w/ .003 - .004" press fit)

 

5.56x45 Caliber

SAIGA 223 BARREL:  O. D. DIMENSIONS
Chamber .867" (22.02mm w/ .004 - .005" press fit)
Rear Sight Base .768" (19.5mm w/ .003 - .004" press fit)
Handguard Retainer .666"  
Gas Block .630" (16mm w/ .003 - .004" press fit)
Front Sight Base .591" (15mm w/ .003 - .004" press fit)
 
GALIL AR/ARM BARREL (threaded):
OAL 18.1875"  (18 3/16") 462mm
Chamber  .735" 21mm x 1.5mm RH threaded
Locking Lug .788" 20mm
Handguard Retainer .687" 8.125" / 206.375mm from breech face
Front Sight Base/Gas Block Combo .632" 16.05mm w/.003" press fit
 
BULGARIAN (KVAR) BARREL:
Chamber   
Rear Sight Base   
Handguard Retainer   
Gas Block   
Front Sight Base  

FAL barrel measurements:
http://www.falfiles.com/forums/showthread.php?s=&threadid=21952