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k31 OBM scope system (includes k31 clamp on scope mount)

k31 OBM scope system (includes k31 clamp on scope mount)

This K31-OBM is intended as an accessory to be used in conjunction with the existing K31 clamp on scope mount.

For those of you who want the OBM as a free-standing unit, I think this is what we can do.
In the past 20 years there are 4000+ of the K 31 clamp on mounts out among shooters. What we did find is that there were some runs of those, which during that time period, were just different enough in the dovetail undercut, that they will not allow the new OBM to slide over the rail.

At first we were compensating those users with a percentage reduction and shipping coverage for a new K31 clamp on mount. It became immediately apparent that it was going to turn out to be a financial mess for us, so we removed the OBM for sale as a free-standing unit. It was simply becoming a downhill deal for us.

This is what I think we can do. Buy the complete combo kit , and when you get the OBM, try it on your old mount. If it does fit, you can return the new K31 clamp on Mount in the original packaging for full credit back to your credit card. I think that's the best we can do for you.

Slide the OBM over the K31 clamp on scope mount dovetail rail, and move forward until it stops. Using Blue Loctite, insert the three rail screws and tighten but do not over tighten! The Blue Loctite will keep them in place.

The next step is to slide the deflector into the provided space between the bottom of the OBM and the top of the K31 mount. There is a relief slot machined into the bottom of the unit provided for that purpose.

Now apply a light grease to the edge of the deflector and insert the 3 small deflector screws down against the crimped edge of the deflector and secure into place. Do not over tighten! Do NOT use Loctite on the screws
Contrary to what you may have heard, the K31 rifles do not eject spent cases the same, one rifle to another. Your deflector is positioned and bent at the point of manufacture to work across a number of K31 rifles with 100% ejection. Yours may not, but you can find that "sweet spot" for ejection by using both hands to gently bend the deflector either up, or down. If that does not allow for clean ejection, gently bend the deflector to th original position an bend just the front side of the deflector, test for clean ejection. You may have to bend just the rear edge of the deflector to accomplish clean ejection. By experimenting, you will find the correct position for 100% clean ejection. Bear in mind it takes very little bending to control the angle of the ejected case.

Should you have any questions related to the fit and function of this unit, please call the Swiss Products Helpline 406 858-2066


    Attention EU customers!
    If your order is in excess of €160 (without shipping), we can now ship to you.
    The required annual licensing for us to ship for any amount less than that is extremely excessive.
    That could change in the future, but it is highly unlikely.
    If your order is in excess of $185.00 (without shipping)  we can now ship to you.
    We are sorry for this situation, but the EU VAT tax laws are firm . And we must comply.

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