I have a customised Springfield which recently had a new bolt fitted. Last month while hunting I noticed that the bolt opened very hard: in fact, I could not reload from the shoulder; this occured after firing as well as while dry firing. Can this be corrected? Also, can the two piece firing pin be converted to a one piece firing pin?

For starters I'd disassemble the bolt and polish and lubricate the cocking cam in the rear of the bolt body. This may not solve the problem but it's a cheap start and just might do the trick!