LPE Precision magazine shims are one of the simplest and cheapest upgrades available for 'gas in mag' guns on the market today. Magazine shims are placed under the gas router on the top of GBB & NBB magazines to push the rubber seal up so it forms a better seal with the loading nozzle which can give some of the following improvements in performance*,

- Improved gas efficiency
- Improved shot-to-shot consistency
- Increased felt recoil
- A small increase in power/fps

Installation is very easy and completely reversible requiring no modifications to the gun or magazines, with the feed lips removed 1 – 3 shims are placed in the top of the magazine under the gas router and the feed lip reinstalled to get an optimal seal against the loading nozzle. Please note that more pressure on the feed lips will be required in some cases to reinstall retaining pins and care should be taken not to damage the pins or feed lips themselves.

Each shim is cut on a shim & gasket cutting machine in the United Kingdom from 0.19mm thick plastic shim sheet.

Tested and confirmed to fit the following Tokyo Marui gas pistols :-

P226, Hi-Capa, M1911A1, MEU, Detonics .45 Combat Master, M92f, 5-7, Px4 Storm, XDM-40, Mk23 SOCOM Fixed Slide

Tested and confirmed to fit the following WE gas pistols :-

P226, P228, Hi-Capa, M1911A1, M9, Px4 Storm, XDM-40, M&P9, TT33

Tested and confirmed to fit the following KJ Works gas pistols :-

P226, P229, M9

*Please note that improvements in performance will vary depending on the condition and/or fit between parts in the magazine and BBU assemblies, they are unlikely to improve a seal between the magazine gas router and loading nozzle that is already optimal.