You are correct that the hand guards are different for these two sights. But, for shooting purposes, you can just remove the hand guard and mount the M1901 rear sight and go to the range. The barrel should not get so hot that you'll burn yourself without the hand guard. You can always look for the appropriate hand guard in the future if you want to keep the M1901 sight. It's all up to you!

The photo from the KCA home page below shows the different hand guards for the different rear sights.

Just a thought. You can certainly keep what you have and learn how to use it well like many others have done.

Good luck!

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