jg m4-s silver particles?!?!
 

hi new to the hobby, but i was just wondering i recently just poped open my upper reciver, and noticed some fine silver particles(looks like silver anti-sieze) toward the rear of the gearbox by the spring area on the outer surface of the gearbox, wondering if this is normal or somting that could possible lead to failure if left alone, ane help would be appriciated thanks

Could be fragments of metal.. I know I had some after my motor spun on the spur gear. but most was at lower part of the gearbox. dunno wtf your could be from. Does it look more like lube or sparkles

looks like sparlkes to me

well i was very reluctant on opening my mech box, but i did aneways to determine the cause of the silver particles, it turned out the sector gear gear was scraping with the spur gear, and that cuased the silver particles.

So shim it properly if you know how. If you don't, maybe give it to a gun doctor?

i plan to after i get a shimm kit and bearings