M16a1 fps issue

[marve114]

Ive got my trusty m16a1 love this gun and regulary use it . Ive got a problem last time i checked she was running at a nice 337fps hop fully off !
Its runnig an AGM GB if it makes any difference
its full cylinder and airseal is very good with an element m95 spring fitted
The problem is i had it apart cleaned out all the crappy grease etc.....
put it back together and the fps has gone up to 360ish
when you adjust the hop unit to full on the fps drops to something like 250-150 and gun sounds different im stumped here guys
regards
lee

[screwdriver]

Re: M16a1 fps issue

all the grease on the piston oring was probably preventing it from expanding as the piston moved foward on firing resulting in the lower fps before you cleaned it.
turning the hop onto full on most guns will cause the bb to jam as to much restriction ,but if it doesnt jam the bb will exit the barrel at a very low velocity causing the difference in sound.
if its 360 with the hop off adjust the hop till it shoots straight and then crono as sites check with the hop set ,not off

[marve114]

Re: M16a1 fps issue

I will try that the ga was like a swimming pool full of grease ! Piston was a little dry so I applied a little bit of grease to that and made sure the vents were clear . If I cant bring the fps down I will have to fit a smaller spring thanks mate

[guard-sniper87]

Re: M16a1 fps issue

if it doesn't work then use heavier ammo :p

but the fps is 250 is when hop is on :S

that should not happen at all, maybe check the hop unit for that problem, give it a clean and re build

[private parts]

Re: M16a1 fps issue

if it doesn't work then use heavier ammo

Your not suggesting he cheats the Chrono are you?

[marve114]

Re: M16a1 fps issue

Dnt worry I woundnt cheat the the crono I will look at the hop if that looks ok il swap the spring for a 1j

[marve114]

Re: M16a1 fps issue

I dont know if its worth mentioning it has a g&p metal 1 peice hop and clear gaurder rubber and nub . All views welcome guys just would like to get to the bottom of this !

[marve114]

Re: M16a1 fps issue

ok changed the spring to what i thinnk is a 1j and my fps has come down to 301-298 fps with hop off !!!! would like 340-345

Some body recomend me a spring PLEASE

[Gaffa]

Re: M16a1 fps issue

M105. Anything rated around here should get around 345 max with hop off .

You may need a lower spring though if buying a Guarder - SP90 or SP100.