Tikka Tac A1 Grip Screw Thread Pitch

Imabballer

The Accountant
Minuteman
Mar 14, 2018
23
10
Oklahoma
Do any of you that have a Tac A1 and have changed the grip know what size bolt they use? I was going to put an mdt adjustable grip on mine but the bolt that comes with the mdt won’t fit the tikka, and the factory tikka grip bolt is too short. I just assumed it used a standard ar15 style grip bolt but apparently it must be some sort of metric thread I’m guessing.

Thanks in advance for any help any of you have!
 
I received my Ergo TDX-0. It came with a standard thread pitch so I used the original bolt to install it. I am loving the vertical grip. It has given me a more natural grip that gives me near 90 degrees for my trigger finger.
 
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