WBP 5.45 and 5.56 Parts Kits
Posted by Chefur on Dec 5th 2023
WBP is the most affordable route to a 5.45 or 5.56 AK in today's market of nearly non-existent surplus AK-74 parts. The affordability comes with some caveats, however.
Durability
I built one of the WBP kits in 5.45x39 and shot 5,000 rounds of full auto to test the WBP parts and my Krink kits.
The good:
- The bolt exhibits zero wear.
- Headspace did not move at all.
- The cam groove in the bolt carrier does not exhibit any wear.
- The carrier tail has very minimal peening - no more than can be expected from surplus parts.
- The front trunnion shows zero wear.
The bad:
- The tip of the firing pin broke off at 2,900 rounds. This has been reported at far lower round counts by other owners.
The firing pin is also completely proprietary in every dimension. I recommend picking up spares.
Building
Continuing with the theme, these parts are completely proprietary. If you use any one of their bolts, carriers, and front trunnions, you have to use all three of them.
The only real detail of these that makes the build different to any other is the magazine well design.
The magazine on the WBP 5.45 and 5.56 kits sits 1mm further back than on a standard AK-74. This means that, when using an AK-74 receiver, you have to machine the back of the magwell to get magazines to fit.
Machining the back of the magwell means the magazine catch is now 1mm closer to the magazine than it should be, and leads to odd behavior. My recommended method is to weld up the trigger guard rivet holes and redrill them 1mm rearward.
Quality Control
This is the biggest issue with WBP parts - specifically, their bolt carriers.
In short, the carrier rail slots are often not machined parallel with the rest of the carrier. This leads to the piston pointing upwards instead of in-line with the rest of the gun. On my most recent build, I had to exchange bolt carriers with Arms of America three times before I got one that was usable, and even then it's technically out of tolerance.