Hello Mike. I would say the top striker is older and the one I'm looking for. The milling looks very smooth and near perfect. I would say the bottom one is exactly like the one I have from the newer contract. From my limited experience, the original contract was for rifles to be built using the same standards of 1919. Then we went to war, the contract was modified which enabled Remington to build them faster and cheaper. The first 30,000 or so had the more precision milling, grasping groove stock, handguard etc. Once the modified contract was approved, Remington started stamping parts and switched to a easier to build stock. It has been quite a challenge rounding up all the correct parts for 4295 and the bolt is my last project to restore. I would have started years ago but until recently, didn't know there was a difference. Regards, Rick.