M4 upgrade question

[VooDooPeteK]

I have a &G M4 carbine (box says gr16 but anyway)... I am looking to upgrade the spring and know I will need to get metal bushings.

My question is how do you know what bushings to get 6,7 or 8mm?

All I know is that it has "Gear Box Reinforced Metal" but not sure what version gearbox or what bushings it will take.

Is there an easy way to tell?

also is there any other parts I would need to upgrade when I put a new spring in? I know I should do bushings but anything else that will wear from the new spring that should be done at same time?

Thanks in advance

[Spike]

It will be a version 2 mechbox, all m4's have them. It should say on the box what size bushings it takes. Otherwise, google should be able to tell you.

I would recommend getting a new piston if you're upgrading the spring. Nice compression parts always increase a gun's performance (CONSISTENT fps= consistent hop up), and pistons have a tendency to be one of the first things to go in a mechbox. What kind of spring are you putting in it?

[VooDooPeteK]

M115 spring from Velocity Arms

the box or the manual says anything about bushings

[Spike]

if you're doing an element spring, m105 will be plenty. Having a gun shooting over 400fps isn't fun for those on the receiving end, and you'd hardly notice any performance increase.

[VooDooPeteK]

OK thanks, and did you have to upgrade the bushings?

thats where I am at a lose cause I have no clue what bushings are in this thing lol

[Skladfin]

you already have metal bushings

just upgrade your piston head, it doesnt compress properly.

[scurvythepirate]

Not just piston head, cylinder head, Cylinder, a probably a tightbore, the stock 6.08mm barrel isn't too great. Mine isn't at least.

For brands Prometheus would be your best bet.

EDIT: Why would you want a spring change? 360-380 is perfectly fine for airsofting, going over 400fps will go against most field rules for fps maximums in a Full Auto capable AEG. Stick to the same spring, and just add what i said, with the added compression help and the tightbore, you shouldnt have a problem getting at least 370fps or more.

[Skladfin]

no, cylinder and cylinder head is fairly good, they seal properly(Even most china clone cylinder and cylinder head seals properly). Airseal nozzle would be a good idea however, and a tightbore because the stock aluminum one scratches too easily. Also a new hop up rubber as well.

Back in like 2008, before the invasion of the cansoft, G&G was one of the top line brands named along with CA, G&P, VFC, and so and so, now it's treated like a cheap whore.

[VooDooPeteK]

OK so piston, airseal nozzle and tight bore..

anyone have suggestions on good ones to get?

I was looking at the super core piston in link below but its only pre order right now

http://www.airsoftparts.ca/store2/in...oducts_id=1681

as for the tight bore and nozzle I have no clue really

also has anyone done the mod in the link below? if so what are the findings from it? (worth it, easy to do and so forth)

http://www.airsoftfaqs.com/technical...-nozzle-2.html

[m102404]

The piston doesn't do anything for compression...the o-ring of the piston head completes the seal in the cylinder.

Match the piston body and the piston head to hedge your bets that the total length of the assembly is correct. Too short and the sector gear will not engage the last tooth of the piston body properly, resulting in damage or failure.

If the piston body and head are fine...you can tweak the o-ring to improve compression.

If you need to buy a new piston body and piston head, the Modify full tooth poly carbonate body and polycarbonate bearing piston head are very good.

The Modify airseal o-ring nozzles are very good.

Systema, Prometheus, Madbull Black Python v2 and other tightbores that Airsoftparts.ca carries are all good. 6.04 or 6.03mm are as tight as you need to go. 363mm is standard M4 carbine length.

Buy a new hopup rubber as well. I really like the Guarder Clear rubbers. Others prefer Promethus, etc.... Up to you. Try a couple of different ones.

Personally...although I get the theory behind that mod, I don't believe that it will hold up under actual use for long. Stick with a nice air-seal nozzle that has at least one internal o-ring and you'll be ok. You can buy a couple of different brands and test fit it to your nozzle. Slight manufacturer to manufacturer differences between the cylinder head nozzle and the nozzle will result in a looser/tighter fit. You want the fit that gives you the best airseal.

Best of luck

Tys