Closest I have experienced was firing a light, pistol gripped 12ga. shotgun with magnum slug loads. The shove is the same IMHO but the initial snap is different. The heavy loaded 500 shoves HARD without much snap but you know something big left quickly.

Firing heavy loads 1/2 a box or 25 rounds makes for a work out. Loaded down you can fire it all day.

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NRA Certified Instructor & RSO