All the guys here have you pointed in the right direction.
22's and their ammo is an unusual situation sometimes.
Here is a story, but with 22 rifles. Well meaning guys had given me 22 ammo over time as a present etc. Some of it was Federal, some of it was Match style etc. I just put it in the storage box as I shoot either the Winchester match or the Remington Green box 22's. Interestingly the Remington Green boxes of 50 shoot fairly well in about every thing I can remember trying. The bulk 22 Remington is suppossed to the be the same ammo - but I have had a LOT more failures to fire, jams, and inaccuracy with it. Somehow I think the boxed rounds have a bit more QC, but that is just my hunch.
Anyway, I had probably 5000 or more of those new rounds and I took it with me to the range to give away. There was a Granddad and a couple of his grandsons on the rimfire range. I offerred it to them and explained that it was a gift that I dont use, etc. But I told him it probably wont shoot to the same POI in your rifles here. They accepted the new ammo, but did not believe the POI too much. 22 ammo is 22 ammo was his thought.
I went on and shot and later walked back over to see how they were doing. There were three groups with three different ammos on the targets - ALL about 8 inches from each other.

Yep, Granddad said " You are RIGHT. I never knew this before."
You may very well need a new sight. But you also might find an ammo that works well inside the adjustment range of your 617 too.
I would look at what your LGS or store stocks that you can regularly buy.
But now you know why those dedicated rimfire target shooters find the one that works and order a big volume of them from the same production lot number.