New net shape strength retaining high temperature alloy parts are formed from fine metallurgical powders by mechanically blending the powders and placing them in die, placing a piston in the die, extending the piston into a driving chamber, filling the chamber with CH4 and air and compressing the powders with the filling pressure. Igniting gas in the chamber drives the piston into the cavity, producing pressures of about 85 to 150 tsi, compacting the powders into a near net shape alloy part, ready for sintering at 2300° C. without shrinking. The alloy parts are Re, Mo—Re, W—Re, Re—Hf—HfC, Re—Ta—Hf—HfC, Re—Mo—Hf—HfC, Mo—Re—Ta, Mo—Re-f-HfC, W—Re—Hf—HfC, W—Re—Ta—Hf—HfC or W—Re—Mo—Hf alloys.