Originally Posted by Savysplace
I recently purchased; I believe to be a French 16-gauge sxs gun. I've done a little research and noticed on the barrel flats there is no "65" marked. Does this mean it would not be a 2 1/2 shot shell size? I've been shooting 2 1/2 RST but would like to shoot some Boss 2 9/16 bismuth for hunting grouse on federal/state land.

thanks for any help on this.

If you have a 2 1/2" chamber, you would be just fine shooting 2 9/16" shells out of it. The 1/16th extra won't make a big difference to the pressures generated. Just make sure the loads you are shooting are suitable for the age and condition of your gun.

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