Anybody know the bore size of a 22 caliber Brocock Batman Hi Lite?

Go with the sample packs as each barrel is ever so slightly different and each barrel may prefer one size over another...snug fit is key, best and cheapest way to find one or more your barrel likes. Might also want to try FX Hybrids as I think that barrel is choked. Also Griffin off eBay as his slugs are swagged, more costly but may fit your breech and lands better. Hopefully you can find an NSA that shoots as they are much more affordable! Good luck!