That is a SBE 1, Buzz. It isnt actually reliable with loads under 1 1/4 oz, according to the instructions.

It isnt actually reliable, period, and I have the receipts from H&K where they attempted to make it so on three occasions.

I think it worked OK with big stuff, 3 and bigger, after H&K was done with it. For years, it was a really expensive single shot, that refused to go into battery, after it was fired.

Im not a waterfowler, and have virtually no use for the gun.

Best,
Ted