It is a two grove and Remington said it was manufactured in January 1944 and that the barrel date would indicate the original. It appears to have never been fired since it was built or rebuilt what ever the case. The man I traded with said he got it from the DMC which is the predecessor to the CMP. The barrel has no wear at all, finally going to get to the range tomorrow if it doesn't snow. The weather forecast is for almost 70 for Thursday so I hope I am OK.