AK Two bangs on one pull

[cannon]

This is a question from another forum I frequent.

Guy has an Yugo M70 ab2 and he pulls the trigger and often gets two rounds fired. The third round would fire but it is a light strike.

Clearly this is a very bad thing on several levels.

He has cleaned the heck out of everything. Still has the problem.

What should he be looking at to get this fixed?

[Gowking]

Check the disconnector to see if it is one of the bad ones that Tapco made a few years ago.

-MRA

[mrlonewolf]

More info needed, is this a brand new gun?, home build?, old gun that was working fine and now is malfunctioning?

As an initial approach.

He must thoroughly check the fire control group, specially the disconnector, disconnector spring and hammer.

Check hammer catch.

Check axis pins for proper alignment.

[atsaubrey]

What type of ammo? Soft primers a possibility?

[Gowking]

What type of ammo? Soft primers a possibility?

That's a possibility but would also require either hammer follow or a sticky firing pin.

-MRA

[Fate]

Glad this one is a hypothetical question.

[phrogg111]

Well, I have seen an AR have the holes drilled just slightly off... The disconnector has to release the hammer, then the trigger has to catch it after that release. If the disconnector releases the hammer, but the hammer then misses the trigger piece, then you'll essentially have two round burst - one trigger pull is two shots, once when you pull, and once when you release.

[SJgunguy24]

Put the spring into the disconnector.

[lugee]

filing down the shelf on the hammer solves this problem. This is common with tapco triggers on the ND3 receiver

[nicoroshi]

filing down the shelf on the hammer solves this problem. This is common with tapco triggers on the ND3 receiver

For hammer follow this is correct but sometimes not needed.
The main cause of hammer follow is the distance between the disconnector, and trigger hook. That distance should be ~85% of the width of the hammer.
If it larger than that the hammer could pass between the hooks without catching either one (depending on how the trigger is pulled).
Get that distance FIRST then see if the carrier isn't pushing the hammer far enough back to catch the disconnector when trigger is pulled.
If that's the case reducing the height of the hammer shelf is the cure.

Also agree with SJgunguy, and MadRiverArms.
Make sure that disconnector has a spring in it, and the hole in the disconnect isn't one of the deep ones Tapco sent out a while back.

[SJgunguy24]

filing down the shelf on the hammer solves this problem. This is common with tapco triggers on the ND3 receiver

The M70AB2 doesn't use the NDS3.
It sounds like a disconnector issue, don't know which FCG it is yet. Something is causing the hammer from being caught by the discon.