Keyholing & 5.45mm

[Jay Cunningham]

At the recent Vickers class we discovered a possible new data point concerning 12.5" barrel 5.45x39mm platforms and Wolf 60 gr FMJ ammo - my weapon was KH'ing some of this stuff, noticed on TD2.

The 16.25" AK-74M clone seemed to shoot it fine, and the 12.5" seemed to run with the Bulgy 53 gr. I need to conduct more testing to see if this hypothesis is valid. Even then, it is only valid for my rifle until we can gather additional data.

I have been subsequently informed that the Russians came up with different twist rates for these platforms, much like we did in 5.56mm.

However, I pulled bullets from both cartidges - they were both exactly the same length.

Any thoughts?

[alistaire]

What twist rate are the barrels?

[Ned Christiansen]

I've seen this with a standard AK74-- keyholing at 7 to 15 yards, then fine further out. They apparently are yawing then getting with the program as they get a bit downrange.

[Jay Cunningham]

I honestly don't know the rate of twist in my AK-105 clone as I acquired the rifle in a trade. Is there an easy way to check the twist rate visually/mechanically?

I tried looking down both barrels (my AK-74M clone is a Bulgy SLR-105) but to me they looked like the same twist rate.

The SBR was not doing it all the time, in fact no one even noticed until the end of TD2.

[Heavy Metal]

I honestly don't know the rate of twist in my AK-105 clone as I acquired the rifle in a trade. Is there an easy way to check the twist rate visually/mechanically?

I tried looking down both barrels (my AK-74M clone is a Bulgy SLR-105) but to me they looked like the same twist rate.

The SBR was not doing it all the time, in fact no one even noticed until the end of TD2.

Put a tight patch on a rod and measure how far it moves to make a complete revolution.