How do you know if the shoulders on a jacket fit?

[bobbus16]

Every single picture I can find of someone in a jacket is like this

with the seam of the jacket on the edge of the shoulder.

But every (casual with no shoulder pads) jacket I have that fits like that has a weird problem. When i move the arms the whole jacket moves too. If I put my arm up the whole side of the jacket goes up with it, so I constantly feel the jacket pulling when I move my arms.

When playing with it I noticed it stops doing this if you make sure the seam of the jacket is 1 inch away from the side of the shoulder (exactly on top of where your shoulder joint is), but it's hard to believe that every picture I can find of someone in a jacket is a bad fit.

 

[Yika]

You be surprised at the number of bad fits.

 

[unbelragazzo]

But also:

1) the jacket movement you're describing is often a result of low armholes, not poorly fitting shoulders
2) the jacket is going to move some when you move your arms, even on a well-fitting jacket.

 

[Brendon]

Hi Bobbus 16
on a lot of the slim fit jackets you will see the arm bulging beyond the sleeve head. In my opinion that is a poor fitting shoulder, but seems to be ok for the gods of fashion.
The movement where your coat moves up when you lift your sleeve is due to the cut of the sleeve height, or the angle of the sleeve behind the crown, relative to the armhole. Watch a conductor one coat moves up and down and the other less.
What can you do about this very common problem ?...if you cannot afford bespoke then shake hands with shorter people as this is not a fitting issue that can be dealt with by off the peg or made to measure and as that is the bulk of the market then it is a problem that most have and should not be something to worry about too much.
go well
Brendon