|If we are talking about firearms, you will not be able to assemble any gun without springs. This item is a part of any high-level weapon, so look for it carefully.|
How to get a metal spring
A spring can be purchased in the "components" vending machine at a price of 60 units of scrap metal per piece. Also find them in containers:
How to create a metal spring (Recipe)
You will need knowledge of the recipe to be able to craft a spring. To do this, on a research table, you need to examine the available spring by spending 250 scrap metal. After that, on the level 3 workbench you can create a spring from 50 pcs. of scrap metal and 2 units of high quality metal.
Recycling of items in a spring
By using a Recycler, you can recycle unnecessary items into a spring. The detailed table of recycling items can be found in the article "The table of items that can be recycled into a metal spring".