There is an animation glitch that causes your soldier to hold both his primary weapon and his pistol when walking while crouched (weapon lowered). This seems to only be visible in third person. Your sidearm appears in your right hand and glitches through your main firearm. There is also a slight animation twitch when changing movement pace.
Will continue to attempt to reproduce the issue and see how often it happens.
{F17463}
-Have both a rifle and a pistol
-Lower your rifle (Double tap Ctrl)
-Shift to crouch
-Move forward at a walking pace, using your freelook to adjust the camera to see your soldier's hand placement on his rifle.
the animation glitch also happens without a pistol in the inventory when just switching between movement speeds.
It's actually nothing to do with your secondary weapon as Tarciop says, the animation just puts a random pistol in your right hand as long as you walk in this way.
Your left hand also changes position to be inside of the weapon, noticeable when using a weapon with a grenade launcher attachment.
*EDIT* Attached a pic showing this, sorry it's not bigger!
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