I had a few USGI 20 rounders that had a missing or loose rivet on the flat spring.  I found a company that carries small 1/16 diameter aluminum rivets, so I got a pack to try replacing the damaged rivets.  They work like a charm - insert the rivet, tap it flat with a ball pein hammer, and that's it.  I used a section of steel bar in a vise to support the magazine and rivet while tapping it flat.

www.microfasteners.com/catalog/products/TNMRVL.cfm

Just though I'd throw this out there for anyone who's interested.  I know it's probably easier to just remove the spring altogether and use a floorplate from a 30 rounder (I have done this, too), but I wanted to try it to see how it would work.  Should make good range mags if nothing else.

Regards,
Dave

Hokiedave,

I have repaired the lower rivet with a standard 1/8" diameter aluminum rivet, peened the inside down  filed the outside head down flat.  This has worked good.  I am glad you listed the micrp fastener website, this will help.

77Bronc

Another solution to the 20 round mag problem is to remove the flat steel piece all together and replace the floor plate with a 30 round unit. I've finally stumbeled across a source of 30 round floorplates.

dsgarms.com/index.cfm?fuseaction=product.display&Product_ID=288]

Hokie, a few years ago I had a few twenty rounders in need of repair, and I don't own a rivet gun. I brought them to a local auto body shop and they replaced the rivets in five mags for a grand total of $4.00.

It might be worth a shot if you can't find another source. Auto body shops use the exact same rivets that we use in our magazines