Seekins Havak PH2 receiver question?

[rmiked]

I removed my scope base to verify torque values on the 5 (8x32) screws. I noticed 2 silver colored small pins visible on top of the receiver in the 1200 position, close together (within 1/2”). The receiver has a recoil lug milled into it protruding up which interfaces with a slot in the scope base. It’s a nice proprietary design. Since it has this recoil lug it doesn’t used a typical “pinned” scope base. The receiver lugs are in the 300 and 900 o’clock positions in the receiver. If I’m not mistaken the bolt lugs ride in the 1200 and 600 o’clock positions until you rotate the bolt 90 degrees. Looks like the 600 o’clock bolt lug pushes the round out of the magazine. Anyway, I have no idea what these small pins do. They don’t protrude above the receiver. This is not the Element design which has a steel sleeve inside the aluminum receiver so these pins can’t be locating a sleeve. Has anyone seen these pins and if so what do they do? I thought I read or heard something related to a floating bolt head but I can’t remember where or exactly what I heard. The bolt is a tool free design to disassemble for cleaning the firing pin. I can’t imagine these pins have anything to do with that. You would never see these pins if you didn’t remove the scope base. Thanks

 

[spife7980]

A picture is worth a thousand words

 

[rmiked]

I don’t have a drawing or picture. I contacted Seekins and the silver pins retain the receiver lugs if the barrel is removed. Apparently the receiver lugs are machined as a separate piece and inserted into the receiver, and bear against a shoulder. If you remove the barrel, the receiver lugs could fall out without the retaining pins. I put my finger in the receiver (bolt open) and pushed on the lugs and they will move slightly forward. I’m guessing 10 -15 thousandths, can’t measure but can feel the movement. So when you rotate the bolt closed the camming action ( inclined plane ) of the leading edge of bolt lugs pushes he receiver lugs rearward. Therefore, headspace must be set by the rear-most position of the receiver lugs. I would have thought the barrel would bear against the receiver lugs, preventing any slight movement of them. This is a very neat design unlike anything I have seen. I am only familiar with Remington 700 style actions. I believe the Seekins design has some floating bolt type design features to ensure near perfect lock up. The non-fixed axial position of the receiver lugs is unusual to me but works great.

 

[rmiked]

If another PH2 owner, could open their bolt and stick your finger on the receiver lugs, I would appreciate letting me know if your lugs also move slightly? The movement will be along the length of the barrel. I’m just wanting to confirm this design feature from another rifle besides mine. You can actually push them back and forth. I’m guessing the movement is 10-20 thousandths but just a guess. Rifle functions fine and shoots great. Just never seen a design that allows receiver lug movement before. Very innovative. Thanks