Magazine spring load calculation

[koza19]

I am trying to verify a customers design of a magazine spring. The spring dimensions are as follows:

Material: Music wire
Wire diameter 0.032"
Width ID .775"
Height ID .157"
Free length 4.85"
Total coils 12

Looking for forces at heights 2.798" & .890". I have attached a drawing for reference

Thanks

 

[israelkk]

Use FEA. But the issues are relaxation with time and may be fatigue. You need to define how much force the spring is allowed to loose over time when the magazine is loaded.