10mm Winchester Super-X Premium Self Defense Ammo for Sale. Box of 20 rounds Retails for $22.50, order yours here for $18.50 per 20, plus small shipping costs. Here is one add: Model #:X10MMSTHP Item ID: 32171 10mm (.400) 175gr ST HP 20 10 Our Price: $22.39 OUT OF STOCK Winchester only makes this ammo once a year, as you will note the above online retailer is out of stock. Very common with 10mm, but you can get yours here today! Please email me at firstname.lastname@example.org, and we will figure out a mutually agreeable compensation arrangement to transfer the funds. email@example.com Thank you.