Full metal M4 lower recevier
 

I have been searching for a KJW, WE, TM or Systema full metal M4 lower receiver without much luck (obviously). Would anyone offer any alternatives or suggestions of obtaining such a precious part (beside painting it black).

They show up in the classifieds every now and then. You can also post a wanted add in the classifieds.

If it helps narrow down your search, Tokyo Marui does not make aftermarket full metal receivers. I know some of their new line up comes with metal bodies but I don't think they create a metal receiver for after market sale at this time.

Are you looking for a receiver for a AEG or a GBBR? Because KJW and WE dont have AEG armalite lines.

I am looking for both AEG and GBB. Thanks.

You're not likely to find aftermarket frames for GBB's.

For the requested brands you listed for GBBR I do not believe aftermarket replacements exist. Everywhere else in the world where GBBRs exist without clear lowers they already come with metal lowers. If you need a replacement part for a KJW gun you usually just contact KJW, however the replacement part in question is a restricted import item. I do know that there are many aftermarket receiver for the WA series GBBRs, although I do not know if there is any compatibility between to the companies for lowers. Unfortunately at this time if your looking to have a M4 GBBR with a metal lower you may have to find a retailer to import a full GBBR for you, or attempt to mod an aftermarket WA style lower to fit properly.

As for for Systema, I do not believe a PTW lower will work for an AEG. Perhaps it could be modded for use with a GBBR however when considering the cost its not really worth it as other less expensive options maybe available.