As I've been building myself an AEG over the last few weeks, I've had debates with various people concerning Aeg's vs Polarstars vs daytonaguns/classic airsoft vs PTW's... and while there is a lot of firmly held believes about brand names, and what mechanism ultimately makes the BB leave the barrel, there is very little proof to support that the firing mechanism itself is chiefly responsible for high precision.

The big problem, as I see it, is that "best" has yet to be fully quantified. We all have witnessed a given person do amazing things with their X, Y, or Z gun, and often times (wrongly) start to attribute the amazing capabilities of the rifle solely with the firing mechanism, without thought to the rifle as a whole.
I propose that polarstars, aegs, ptws, and others' precision is largely a function of parts other than the firing mechanism itself. It is often the case that someone who was willing to spend money on a polarstar, or a PTW, etc, was also willing to spend money on improving the other aspects of their rifle, which incorrectly leads the perception that one rifle style is better than another.

So what makes one airsoft rifle better than any other given rifle? There are many variables that play into it, but in my opinion a good rifle will have (at least) these three characteristics:

1. It will be mechanically reliable.
It will fire every time the trigger is pulled without fail.

2. It will be precise.
It will hit the same spot over and over again as long as you don't move the rifle

3. It will be accurate.
It will hit where you are aiming at, all else being equal.


There are other factors: cost, fit and finish, presence of accurate trade marks, availability of replacement parts, and more to be sure.

However, I consider the first three to be paramount when deciding what rifle I will field personally. In order to achieve these top three items, I do the following when I am building a rifle.

1. Mechanical reliability; I choose parts that have proven to be reliable over time from many users. Ultimately money spent at this stage will be the best spent, as it will make sure that you can go out to the game every weekend and not worry about whether or not your gun will be down or not.
This list is for parts individually that I use and have had good success with. I don't recommend any particular pre-built gearbox options as they all require something in order to be 100% reliable.

Caveat: Manufacturers in airsoft have their ups and downs in terms of quality control, and while this list is accurate as of this writing for my experiences, the next batch from a given company could be utter garbage, so always do up-to-date homework before you buy. With that in mind...

Lonex: makes exceptionally good pistons, bushings, gearbox shells, gears, motors.. in fact, they're my favorite brand on the market at the moment for most parts.
Core: makes good gears, I'd stay away from their pistons
SHS: hit or miss quality, however for the most part their gears and metal rack pistons are good
Seigetek: Best gears on the market, period. They are expensive, but I defy you to break a set on anything under 4J.
G&P: Good motors. The rest of their stuff is good, if average for the price.
JG: Their neo motors are great, good quality gears.

There are many other brands that are ok, good, or even great, but many of them are simply re-brands of the above manufacturers.

2. Precision:
In order to gain precision, you need repeatability. That is, every time you pull the trigger, the bb will follow the same rough path every time.
This is a more complicated area, but chiefly you need the following:

a: A good air seal. Check to ensure that you have properly assembled everything that there is no air leaks anywhere in your system. Properly stretched piston o-rings, a good o-ring air nozzle, and good hop up unit are key to this. There are other techniques involving anything from silicone glue to teflon tape to improve air seals throughout the system.

b: A high quality barrel. This does not mean a tight bore by any means. In fact tighter is worse. You generally want at LEAST .05mm of barrel diameter difference between the ammo you plan on running, and the bore of your barrel. Keep it clean, and keep it DRY. Also, ensure that it is supported for its full length. Barrel harmonics play hell on precision on guns that have un-supported inner barrels hiding inside mock-suppressors. They may look tacti-cool, but they hurt precision.
Also, as  a general rule avoid coated barrels. Stainless steel is the best, followed by brass, followed by aluminum, followed by everything else, in my opinion.

c:A high quality hop up bucking/packing. There are various styles out there that are good, but generally flat-hop, bridge-hop, and r-hops are the best that are out there. Choosing the appropriate sleeve that matches your FPS output is also important.

d:High quality ammo.  Its like having a $100,000 sports car, and being too cheap to buy premium fuel. It might run, but it won't run to its potential. Cheaping out on ammo is probably the worse thing you can do. Whats the point of investing all the time and money into a gun and time traveling to games only to miss your target because you saved a dollar the day before on a bag of cheaper ammo?

3. Accuracy: Buy optics that make sense for your intended role, and zero them in. Airsoft does not have enough recoil to seriously jostle optics around like real-steel but never-the-less make sure that your chosen optics/sights can take a couple bangs without losing zero. Once you have precision nailed down, properly zeroed optics is the only mechanical aspect of accuracy that comes into play. The rest of it, is up to you, the shooter.

This may be changed and updated from time to time, but as it is now it reflects my 13 years of experience with building and tuning airsoft rifles of all breeds.

I'm tired of working on KWA guns that are broken. They're a pain in the ass, and frankly, they're expensive to maintain compared to almost every other gun on the market because you're stuck buying KWA parts.

Here is a list, partially compiled by me, and mostly from other techs I know, about some of the bad things about KWA products.

18gauge wire which is too small for the amperage even a mediocre AEG will draw

Gearbox Painted inside and out (leads to paint chips inside the gearbox)

Spring guide tabs break frequently

9mm bearings (frequently reported to fail)

Trigger trolley stop (too thick; blocks use of some gear sets)

Trigger contact/trolley failure due to load (didn't bother using a mosfet, dispite their "lipo ready" claim)

Electrical (selector plate) safety which can short/corrode

Trigger axle to trolley height off spec (replacement trigger units won't work)

Cylinder head retention nubs over-sized, wont fit non-kwa (ie: standard TM-spec)

Gearbox "reinforcement" material over allowable width

Flexing upper/tab failure/piston forward requirement to open

Full floating barrel (both ends) reduces accuracy/not GB justified

2GX bucking

Hop chamber off spec (other bucking incompatible)

Aluminum flat faced piston head

Insufficient cylinder head buffer  (read:broken gearbox shell)

AOE adjustment absent

Unported piston head (all sorts of problems can occur ... ultimately it makes the piston,gears,and motor work harder)

plastic hop unit (two piece proprietary)

Tamaya connectors (multiple in some models) (high electrical resistance, which gets worse as they heat up from full-auto use)

Un-vented grip on many models

ferrous motor (low torque)

Grip connects to gearbox with only two screws

Self tapping screws (don't hold torque very well, easily strip, when they strip they are different than every other gearbox on the markets thread pitch and design)

No bearings on spring guide and piston head (washers adding mass to the piston assembly)

Springs not ground flat

Lack of piston tooth reinforcement (strips pistons)

Gear axle center distances off-spec (there is a difference between "kinda fits" and on-spec.. which can lead to catastrophic failures down the road even if it "works" right now)

unshimmed from factory (new "self shimming" features) ... which WILL eat itself alive over time, whether with using high amperage lipos or not.

The precision needed for unshimmed gears was never seen in a KWA gun. They took short cuts instead, to keep everything running well. Their bearings are a good example. One issue they have is that the gears are not made to proper spec, so the gears will actually get stuck in the bearing posts, meaning they are impossible to shim. However, because they are in bearings, they still spin. Even when the parts are well made enough for the gears to properly sit in the bearings, they are not shimmed, the gears are loose and wobble in the gearbox. This magnifies the issues of a painted gearbox and weak bearings, as this can increase the likelihood of the bearings failing and increase the wear on the inside of the gearbox, increasing the paint chips..

Not to mention, there is no mosfet... which again, means it is not lipo ready.


TL;DR: There are a lot of proprietary parts in KWA aegs, and while they might shoot "fine" stock, for a while, as soon as you want more from it, it will require almost full gearbox and internal parts replacement in order to be truly reliable.

Granted, many of the problems listed here are present in other companies as well, but none of them collectively have this many issues, or at least none of the mainstream reputable companies do.
Many of the issues are intentionally done by KWA to ensure that people HAVE to buy KWA replacement parts, which they seem to design with engineered obsolescence in mind. Intentionally making weak, proprietary parts which will fail, and forces you into a market they alone control.


Credit to HS5, and star_folder from airsoft society and mechanics for their helping to compile this list and some of this info.

Hey guys, been restoring my old Sun Project M40A1 and was posting its progress on another forum I frequent, figured I'd post it here as well and see what the AZ folks thought.

I've had this SP M40A1 (pre- XB) for about a decade. I bought it from stoneeaglewolf, who was and continues to be one of the best airsoft snipers I've ever witnessed. He'd regularly get many kills with this rifle per game, shooting 400 fps w/ .20g bbs, against people with full-auto aeg's shooting the same velocity, and rarely take a hit himself.

Anyway.. the rifle got painted a green color during his ownership.. and at a later date, I decided to paint it a semi-quazi-sortof desert multicam pattern. Now, I want to restore her to her former glory and strip off all the years of layered and cracked paint and reveal her beautiful wood underneath. I've basically just used an entire can of paint stripper and the stuff made a dent, but the base coat of the paint he had used is stubborn and is barely coming off..

Here she is, as she sat right before I started the process (sorry, didn't think I was going to post this project so I didn't take any better "before photos")



This is the ultimate goal:





Now for some weeks of work:

After stripping it three separate times with liquid paint stripper.




Here is some progress, after about about 2 hours of sanding with 120 grit, then 220grit sand paper. Still need to get the pistol grip area and front end a bit more, and then move on to finer grits.



Now, having sanded down the stock more, and coated it with a coat of cabernet. The wood has definitely seen some action, being a rifle that is over 10 years old which saw a fair bit of crawling around in the dirt and mud, but its cleaning up.

It's not the original walnut color that it was way back when, but I prefer more red tones like cabernet and cherry. The color is a bit lighter than in the picture.. was having trouble finding good lighting.




Will update next with the stock when its finished, as well as when I start working on powdercoating the metal parts.

My MBR:

H&K MR556A1 (HK416) gas piston upper on a Smith and Wesson M&P15 lower with H&K internals.




Backup:

DPMS M4A1



Plus a few glocks and a target pistol which I'll snap photos of eventually.

Razer Imperator 5600dpi gaming mouse, in good condition, has adjustable reach thumb buttons for different sized hands.

Has on the fly DPI adjustment, and pre-programmable profiles that are stored in the mouse's onboard flash memory. 50g acceleration and 200 inch per second tracking, 1000hz polling rate, 24k gold plated usb plug, braided fiber cable, 7 independently programmable buttons. This thing is badass.

The left mouse button sometimes double clicks if you tap it too lightly, but if you use normal force it works fine. It's an easy fix if it bothers you or if you even notice(posted on various gamer forums), I just wanted to be as honest as possible. Depending on your clicking style (lol), and computer usage,  you might never notice.





$25. Paid $85 for it about a year ago.

Sold

I was debating picking up an order of black bioval .30g bbs. Who actually runs black bbs though?

Comments welcome.

Hey guys, I'm in the market for a PTR91 or similar G3 clone rifle. Project rifles are OK, but just curious if anyone has anything worth buying.

Thanks.