The first centerfire game rifle I bought was a Ruger M77 (200th Anniversary of American Liberty) 257 Roberts. That one liked Nosler 100gr Solid Base bullets (pre Ballistic Tip hunting) and a moderate charge of IMR4320 powder. It also shot a 75gr Sierra fairly well. Many years later, I bought a Ruger M77 MKII Ultralight that only wants to be fed 120gr Speer BTSP bullets and a stiff charge of Hodgdon Hybrid 100V powder. Others comment about how easy it is to find an accurate load for the Roberts, but my limited experience is completely different.
