Technically yes, but other parts would also have to be changes and Crosman only provides information (EVP’s) on the parts needed to repair a gun to original configurations.
We do not recommend modifying your gun and specifically warn against it in the manual.
I would recommend adding a new Benjamin Trail NP2 Synthetic in .22 Caliber, (Model: BTN292SX) to your gun rack. The TR77 is a very nice rifle , but if you want (or need) more power and a smother shooting gun, the NP2 is the way to go.