Comparison

Mountain River vs Blue Moon Bay

Valspar 4005-6C and Vista Paint 7301, ΔE 2.48 apart

Valspar Mountain River 4005-6C on a wall, hex #3F576A
Mountain River Valspar 4005-6C
Vista Paint Blue Moon Bay 7301 on a wall, hex #435466
Blue Moon Bay Vista Paint 7301
Zeytin’s verdict · ΔE 2.48Close cousins. Paint a sample of each before you choose.

Valspar Mountain River (4005-6C) and Vista Paint Blue Moon Bay (7301) measure a delta-E of 2.48 apart. They sit within 0.9 LRV points of each other, so neither will look brighter than the other on the same wall. Both carry a similar amount of color, at chroma 14.3 and 12.7. The undertones part company: Mountain River reads as a blue at hue angle 255.0 degrees, Blue Moon Bay as a blue undertone at 262.1. Close, but a large sample of each will show the gap, particularly against white trim. If you need the Blue Moon Bay depth in Valspar's line, start from its LRV of 8.0 rather than matching by name.

Is Valspar Mountain River the same color as Vista Paint Blue Moon Bay?

Not quite, but close - Valspar Mountain River and Vista Paint Blue Moon Bay are delta-E 2.48 apart, close enough that most rooms would not show the difference.

What is the delta-E between Valspar Mountain River and Vista Paint Blue Moon Bay?

The measured color distance between Valspar Mountain River and Vista Paint Blue Moon Bay is delta-E 2.48.

CLOSEST PAIRΔE 2.48 Mountain River and Blue Moon Bay
LIGHTESTMountain River LRV 8.9
DARKESTBlue Moon Bay LRV 8.0
SPREAD0.9LRV points

Side by side

measured values
Mountain River Blue Moon Bay
Brand Valspar Vista Paint
Code 4005-6C 7301
Hex #3F576A #435466
Light reflectance 8.9 8.0
Undertone blue blue undertone
Chroma 14.3 12.7
Hue angle 255.0° 262.1°
Color family black black

Each on its own

full detail