Funny you should ask. For a time I loaded the 63 gr Sierra SMP, but just punched paper with it. But one day a buddy and I got invited on a pig hunt down near Victoria, Texas. The buddy didn’t have a rifle, so I loaned him my 220 Swift tang safety rifle and some 63 gr ammo. It was the only extra rifle I had back then. He and I were in high seats in the back of a Jeep when a bunch of hogs came running by. The buddy shot the big one, and that hog dug a trench with his chin. He shot a few more when we were there and didn’t lose a one. Just for info, I had the bullet moving at about 3300 FPS.
When the 65 gr GK came available, I called Sierra to get some load data. I was told to use the loading data for the 63 gr bullet, due to the bullets having the same bearing surface. But, it wouldn’t stabilize in the 220, so I parked the bullets in the workshop. Later, when I got a 223, I used the Nosler Partition bullet, but accuracy was only Ok. So I dragged out the 65 gr GKs and found great accuracy with A2230 and H335. And, since every time I went coyote hunting, pigs would show up, I thought I’d try it on the pigs. And it worked great. FYI, I load it to about 3000 FPS, over H335.
Probably more info than needed, but there it is anyway.
