Turkey neck...
Spend ~10 mins on these charts. Write down a few calibers, and recoil info. Compare the 20 gauge to different rifles. Keep in mind that a shotgun recoil is also faster than a rifle.

Rifle Recoil:
http://www.chuckhawks.com/recoil_table.htm

Shotgun Recoil:
http://www.chuckhawks.com/shotgun_recoil_table.htm

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For what it is worth: I still agree with me!
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