As I have seen 2 of the same model of firearms within a few serial numbers of each other both prefer different ammo so all you can do is try. I have had good luck with groups from Blazer’s 22 ammo and it’s not that expensive. I am interested in the Henry AR-7 so let us know how you make out with grouping. I really want one for stand hunting deer here as I could put the firearm in my back pack for the walk in.
A guy at the gun club used to own one and said he couldn’t get the thing to shoot consistently. He figured because one site was on the receiver and the other on the barrel every time you took it apart or put it together the POI changed.