AOSC Forum Archive

Ok, so I finally have a gun for my long-debated PDMR build. G&G FN2000. Here is my build list, and I'd love some critiques, suggestions, etc. Goal is 400 with a .25, obviously the full auto limit.

I know the barrel is about 25mm shorter than stock, but it was of no cost to me (a couple hours of labor,) so why buy a different one.
Not sure if I need to Swiss cheese the piston, but it sounds fun. May as well.
Forgot to add to polish the cylinder and teflon tape the cylinder head to the mods list.
Any other mods I should do to get better air seal/consistency in FPS? Ideally I'd I like to to be one of those 398+ or - 2.
Trying to volume it for .32s. Does anyone have a type 2 cylinder they can measure from the port forward?




Thanks for the input.

are the bushings metal??

and maybe a type 1 cylinder. Ill measure a type 2 when i get home if no one does it by then

Kory recommended the type two, as he said he was using a type one and slightly overviluming with a 395 with .32s. But a measurement would be appreciated so I can do the math.

You can do the math without knowing the measurement...

Basically, solve for X:

(pi) * ((6.03)/2)^2 * 407 * 1.8 = (pi) * ((23./2)^2 * x

That's the area of the barrel times 1.8 put up against the area of the cylinder. X is the length needed for the cylinder, the useable length. 1.8 comes from barrel to cylinder ratio. You could probably do fine with a 1.7

Is 47.027 a logical number?

-no Swiss cheese
-Get the 15 not the 14 tooth and glue the rack in firmly
-radius the shell

Would superglue and clamping it be sufficient?

Take the steel rack out, make sure everything is clean and dry, apply a tiny amount of cyanoacrylate down both sides in the grooves that hold the rack, and slide it back in.

Cyanoacrylate as in super glue?

Many super glues are, but not all.

I've always found M135s to be perfect. With the adjustable spring guide you might as well use a M140.

**I started writing out all these good mods to do to FN2000s and then I remembered they've already been done to this one..... booooooooooring**

Don't forget a suppressor. Minimum of 340mm should do.

So if I want it to be 400 w/ .25 but able to back out to 400 w/.2, what spring?