There were very few parts of the original A1 SA80 that were not poorly designed or produced, even the humble magazine was a source of constant problems. Briefly soldiers found it was prone to jamming on a regular basis, the original catch was too shallow so magazines could drop off- this was replaced with a slot that helped hold the magazine in more securely but let mud and dirt into the magazine. It had unreliable feed lips and did not always present cartridges at the most appropriate angle to feed into the chamber reliably and the metal the magazines were made of was thin enough to allow them to buckle inwards if excessive pressure was applied- again causing feeding problems.
When the German company of Heckler and Koch redesigned the weapons system they spent a lot of time improving the magazines:The new magazine has a new smoother shape to allow the follower to feed the cartridges more easily. The follower was redesigned with an improved profile and was made of stainless steel:This reduced friction and improved feeding. The feed lips were also improved and the prominent fold of steel on the front of the old magazine has been deleted in favour of a stronger welded design:These magazines are of course for 5.56 NATO ammunition. A new magazine catch rebate was designed that did not cut into the body of the magazine and thus let in debris:A steel base plate is fitted to the magazine and this is engraved with the HK logo:By pressing in the tab on the base of the magazine with the tip of a cartridge it is possible to completely disassemble the magazine:The spring is a different profile to the old magazine and is painted red so it is clear which sort of magazine it belongs in.
These magazines were a huge improvement on the old A1 designs produced by Radway Green in the 1980s, but are themselves now being superseded by polymer magazines with clear plastic viewing windows in the side walls.