. I have only shot a few groups out at 100 yards and they all seem to fall right around MOA with a few even under MOA. I mostly zero at 50 and then go hunting. Those H&N slugs are also dynamite on ground squirrels. 
Is the barrel you mentioned an after market part? If yes, who sells them and at what price? How many brands and weights of slugs have you experimented with? That’s the first time I have ever heard of using Goo Gone on any ammo-ever. Since Goo Gone is a petroleum based concoction, do you experience diesling? I have heard of guys putting petroleum jelly in pellets to increase velocity, but I would never do it-especially in a springer.FX Panthera 600mm .22 Superior Heavy Liner (polished liner). H&N 30gr HPII .217 diameter (lubed with Goo Gone). Tuned to 945-950fps. This combo gives me outstanding groups at 50 yards which is my zero range. Not just a few cherry picked groups but nearly every five shot group off of a solid rest comes in under a half inch. This rifle will also tell you right away when it wants to be cleaned
Kenny
Impact m3 700mm 22. Patriot .217 slugs are my favorites in 23 gr and 34gr 60-150 yards but I've gone to 400 with it for fun.
No, not an after market barrrel. It’s an FX Panthera with the 600mm barrel and the Superior Heavy liner. I did polish the liner. I have polished the liners on all of my FX rifles. I actually use Goo Gone to clean my air rifle barrels. It works great. I haven’t had any trouble with it. Although I use it very sparingly. When I lube my slugs with it I add a few drops to the foam in an empty pellet tin and then roll the slugs around on the foam. Then the slugs are rolled around on a dry paper shop towel to remove any excess. I’m still comparing Goo Gone to Balistol as a slug lube and haven’t decided which one is best. Neither one has given me any trouble at all.
