What is the best way to UV unwrap these?

Help and Feedback Art Design Support
1

I am trying to unwrap these 3D models:

image
image1397×705 416 KB
– Walther PPK
image
image1421×715 296 KB
--Supressor
image
image1189×529 167 KB
--Magazine

image
image1441×715 403 KB
AK-47

image
image1475×741 235 KB
– Remington 870

Problem is that I can’t figure out how to unwrap it in a way that avoids islands stretching.