Yes, they used the same screws on all three-screw single-actions up until the time the New Models were introduced in 1974.
At that point the two rear screws were changed.
But the front screw today fits all New Model Bearcat, Serial # Above 93-00000, .22; New Model Blackhawk; New Model Single-Six; Old Army, .45; Old Model Blackhawk; Old Model Single-Six, .22; Old Model Super Blackhawk, .44 Mag; Super Blackhawk, .44.
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