Professional gunsmith guide to AK-47 and AK-74 platform breakdown, disassembly procedures, component identification, and maintenance specifications. Technical reference for verified gunsmiths.
The Kalashnikov platform represents one of the most widely distributed rifle systems globally, with the AK-47 and AK-74 serving as the foundation for countless variants. Professional gunsmiths must understand the complete breakdown procedures for both platforms, as these rifles frequently require service, modification, and repair work. This comprehensive guide covers the systematic disassembly process for both 7.62x39mm and 5.45x39mm variants.
While both platforms share fundamental operating principles and basic field stripping procedures, significant differences exist in component specifications, tooling requirements, and assembly tolerances. The AK-74's refinements over the original AK-47 design include lighter bolt components, modified gas system parameters, and the distinctive muzzle brake assembly that requires specialized removal techniques.
Essential Tooling Requirements
Professional AK platform servicing demands specific tools beyond standard gunsmithing equipment. The AK sight adjustment tool allows front sight post changes without staking damage. An AK trigger guard retainer tool removes the trigger group without receiver damage. Barrel pin punches sized for the large AK barrel retaining pins (typically 7/32" and 1/4") are essential for full disassembly.
The AK-74 muzzle brake requires a specialized spanner wrench for removal—improvised tools will damage the brake's engagement notches. Headspace gauges in 7.62x39mm and 5.45x39mm allow post-service verification. A trunnion block for vise mounting prevents receiver flex during high-force operations such as barrel removal.
| Component | AK-47 / AKM | AK-74 |
|---|---|---|
| Caliber | 7.62×39mm | 5.45×39mm |
| Barrel diameter (at receiver) | 0.810" | 0.785" |
| Gas port diameter | 0.114" | 0.100" |
| Bolt carrier key | N/A (piston integral) | N/A (piston integral) |
| Muzzle device thread | 14×1mm LH | 24×1.5mm RH |
| Magazine well | 7.62×39 dimension | 5.45×39 dimension |
Field Strip and Component Removal
Begin with safety verification—remove the magazine, retract and lock the bolt carrier, and visually inspect the chamber. The AK field strip sequence proceeds without tools: depress the rear of the dust cover and lift it free, retract the bolt carrier to remove the recoil spring and guide rod assembly, then slide the bolt carrier and bolt forward and out of the receiver.
To remove the gas tube on AK variants, rotate the gas tube lever on the rear sight block 90 degrees and lift the tube free. The gas tube accumulates significant carbon fouling and should be cleaned thoroughly at every service interval. AK-74 gas tubes use the same removal procedure as AK-47 variants.
Common Service Issues
Gas port fouling is the most common maintenance issue on high-round-count AKs. The AK's long-stroke piston system is tolerant of fouling, but significant obstruction reduces bolt carrier velocity and causes cycling failures. Clean the gas port with a properly sized drill bit rotated by hand—never use a power tool, which can enlarge the port and permanently alter gas system timing.
Extractor breakage occurs more frequently on AK platforms than most other rifle designs due to the aggressive extraction geometry required for reliable function in adverse conditions. Stock AK extractors in quantity for platforms used in high-volume training. Inspect the extractor at every detail strip for chips or hook wear, and replace proactively at 10,000-round intervals.
Headspace verification after barrel-related service is mandatory. AK headspace specifications are generous by Western standards, but severely excessive headspace causes case head separation. Use a go/no-go gauge set appropriate to the caliber after any barrel work or trigger group service that involved the front trunnion area.
AK-47 vs AK-74 Service Differences
The AK-74 muzzle brake is a significant departure from the AK-47's threaded muzzle. The AK-74 brake uses a right-hand thread (14×1mm on Soviet-spec, 24×1.5mm on some variants) and is retained by a cross pin. Remove the cross pin before attempting to unscrew the brake. Attempting to unscrew a cross-pinned brake without removing the pin will strip the threads or break the brake.
AK-74 bolt carriers and bolts are not interchangeable with AK-47 components despite visual similarities. The 5.45×39 bolt face diameter is smaller than the 7.62×39 version. Always verify component compatibility using part numbers or caliber-specific gauges before installing any bolt assembly.