How to properly uv unwrap..clueless

so, i’m confused about this uv wrap thingy. i just started 2 months of learning.

I just modelled a shotgun, and there’s aiming barrel made by strecthing cube.

and applied the texture, and it looks so strecthy. Tried to do mark seam but have no idea where i place it so yeah, i just did mark seam, and the texture even more worse stretch.

How to properly do this?

i used subsurf modifier.

the UV now weird after i unwrapped it with mark seams on BOTH ENDS, before it was like a cube

here’s the video for more clear whole object

Heyo, need to mark a seam along the longest side as well

Imagine you have a cardboard box that’s the same shape, how are you going to flatten it?

yay it worked, but have a another problem, see the textures, something is not right (look at the edges)

That unwrap looks kinda weird, might be unapplied transform values.

Try ctrl + A
then select scale and rotation.
Then do the Unwrap again.

About the issues at the edge.

Stretched Textures. It is natural result of the subdivision modifier. You can lessen its effects by adding edge loops closer to the edge. The stretch will still be there but it will be minute.

Seam lines. This is because the colours(from texture) at the UV edges that are supposed to join together (in 3d) are different. Fastest way would be to paint over it with the clone brush. See the topic linked below.

Good luck!

Hope it works!