Umarex 420rds Magazine for UMP

Despite everything you can read on the internet and on on the manufacturer's manual, we recommend that you never introduce silicone or grease into airsoft magazines. Greasing has a devastating effect on a replica since it will directly grease the hop-up rubber and inner barrel, resulting in a loss of precision and even more accentuated dust fixing. Never introduce chemical products such as grease, silicone spray or any other kind into the magazine, the hop-up unit, the BBs, the internal parts of the AEGs. The silicone is only used on pneumatic parts such as a gearbox cylinder or a moving O-ring. Special recommandation regarding Mid-cap Magazine :

• Limit the number of bbs by 70-80% of the mid-cap capacity, never force the introduction of the BBs with a BB loader.
• Too many BBs can slow down the operation of the nozzle and that can have repercussions on the trajectory of the bbs and the feed.
• If you want to keep your magazine for many years, it is also imperative for not working the spring to the maximum of its capabilities.
• Never store your magazine filled for a long period of use, the spring loaded for a long time may be irreparably damaged with a settling effect.
• Use BBs with irreproachable sphericity