Hi,
I need to add some length to the feed tube on the ammo tin on the 30 cal, I was wondering where to get a long spring of the right sort of diameter / length. Any suggestions?
Thanks,
Ranj
I've got this listed in my favourites from years ago when someone else did the same thing:
http://www.strutsdirect.co.uk/component ... 91d9112f17
Other than that, you can use plastic tube from B&Q!
Ah ha! Plastic, I suggested that and was pooh poohed as some kind of cretinous fool!
I didn't want to use plastic tube, If it was internal it would be okay, but it will be external, exposed and subject to being trodden on, crushed by heavy handed operaters and creinous fools 
Thanks evo, that looks ideal.
The shipping costs more than the spring!
Making your own is a doddle if you can't find a replacement easily.
You need a vari speed drill, some bits for it, wire cutters and some high E or B guitar strings.
Get the drill bit (usually about 0.5mm smaller than you want the final diameter of the spring to be), then lock the start of the guitar string in the chuck of the drill with the drill bit.
Keep the string at an slight angle and nice and taught.
Now turn on the drill and watch as the guitar string wraps round the drill bit, forming your spring.
Then when you have the neccesary length just trim the edges with some wire cutters.
If you want a stiffer spring just use thicker guitar strings.
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EDIT :- On re-read this maybe wont work for that size of spring after all mate. Its fine for wee fiddly bastard springs that fit in pistols etc, but > 6mm maybe pushing it.
AGM MP40 - AGM STG44 - CYMA Thompson M1A1 - WE P08 4 inch - Marushin M1 Carbine GBB - AGM Sten MkII
I didn't want to use plastic tube, If it was internal it would be okay, but it will be external, exposed and subject to being trodden on, crushed by heavy handed operaters and creinous fools
If the tube goes through an ammo belt, it'd be protected to some degree.
@greedo198 - No, This needs to be a long spring but that method sounds ideal for the trigger switch spring for the garand which has disappeared yet again 
@No1_sonuk: No, it doesn't and even if it did the ammo belt would be stuffed in to a tin and the tube would most likely get pinched/squashed then. In my experience it is better to assume that if it can get knackered it will, so over engineer it just in case. After all, we actually bent the .30 cal because the builder either didn't anticipate the forces it would be subject to in a skirmish or overestimated the strength of 2mm aluminium plate and aluminium welds.
Ranj I think I have an old feed slinky hose off an old A&K M249 box magazine, I'll see whether I can find it, its about 4 inches long?
Greedo, top marks, I used your suggested technique to make a teeny spring for my garand's trigger switch and, as suggested on a camera repair website, I baked the spring in the oven for an hour to improve "springines" for want of a better word. It works fine 
what diameter tube did you use for the feeding tube? and where could I source some?
the link for the feed spring is perfect 
