I have both 12 & 20 USH's. the 12 is by far the most accurate slug gun I have ever fired. thats why I bought the twenty. I havent fired the twenty yet.
My 12 likes the Rem ammo. Copper solids shoot in one cloverleaf hole at 100 as do the Ultra Lokt's. they just print about two inchs higher. Past two years I have switched to the Buckhammers. they are not as accurate. Still cloverleaf or very close to it but these buch hammers, absolutely HAMMER deer out to 100 yrds. Now I carry a couple Ultras and load the gun with Hammers. If something really good steps out in a field at say 200....I just load the ltras and drop him where he stands. Otherwise I just use tyhe hammers. I really love this gun!!
CW
Here is one of the last groups I shot with mine useing the Buck Hammers. You have to look close at the bottom hole to see its everso slightly "egg" shapped:
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In this one you can see the differences between the Hammers and the Ultras. (its the same pic, with a larger view)
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CW