When installing a 14-30R dryer receptacle, do I need an additional ground connection to the box?

Question

Thanks to Stackexchange's Hot Network Questions, I found out that my 3-prong dryer outlet was a safety hazard and I'm replacing it with a 4-conductor 14-30R receptacle and matching cord. I've replaced the dryer cord and now I'm working on the receptacle. The circuit feeding the dryer has a 4-wire cable, with the ground wire screwed to the old 3-prong surface-mount receptacle.
I had been thinking that in addition to connecting the ground wire to the new receptacle, I would also need to run a ground wire from the ground terminal on the new receptacle to a ground screw in the metal box I'm mounting the receptacle in. However, the new receptacle seems to have a built-in solution to this problem: the ground terminal has a metal strap connecting it to the mounting plate. So it seems to me that once the receptacle is screwed into the box cover, and the box cover to the box, the box is grounded and therefore I don't need a separate ground wire. Is that correct?
A few other details:

The new receptacle is a Utilitech 2105S.
I am planning to mount it in a RACO #8232 4-inch steel box, surface-mounted on a concrete wall, using a RACO #810C steel box cover.

Here's the metal strap connecting the ground terminal to the outlet's built-in mounting plate, which in turn is screwed into the box cover:

Harper - Reinstate Monica · Accepted Answer

Anytime you have a metal box, you ground the metal box FIRST.
When the receptacle's yoke has hard-flush metal-metal contact with the junction box cover, and the cover has hard-flush bare metal-metal contact with the junction box, then it picks up  grounding that way.  There are other ways as well.
However, you NEVER connect the ground wire to the receptacle and fail to ground the metal box.  In that case, the box's grounding will fail if you remove the receptacle.
"Grond the metal box first" works well for pushing the ground wires out of the way into the very bottom of the box.  When using one of the allowed methods of grounding a recep via the box, it means you don't have to handle ground wires at all when trying to assemble the box.  One less wire to wrestle!

NoSparksPlease · Answer

Metal boxes must be always be grounded.
For a surface mounted metal device box NEC 250.146(A) allows omitting the jumper to the device if the yoke mounts flush and at least one paper washer is removed or omitting the jumper if using a cover mounted receptacle if the cover and box are "listed as providing a satisfactory ground...".
Really the Code paragraph is a little long and detailed, if you wish to omit the jumper between box and receptacle I suggest you find a quote of NEC 250.146(A) or read it directly on the NFPA website.
Edit: The Hubbell product page for the 810C indicates it meets the requirements of the NEC Article 250.146(A) that allows connecting the ground only to the box.

When installing a 14-30R dryer receptacle, do I need an additional ground connection to the box?

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