Samurai

All I can say is that I've tried it and there was no noticeable difference to a decent hopup rubber. The fellow airsoft mechanics I know and tried it, said the same. There are simply no magical things in airsoft unfortunately. These are like the miracle fuel savers for cars. They do sound good, but they just don't work. Find the hopup rubber your gun likes, assemble the gun correctly, clean the barrel and the rubber with soapy water and then alcohol. If your barrel is not very good, get a straight one, like Marui, or the better precision barrel brands and use the best quality bbs. If you do this, you get the best performance you can have in AS.

If you shoot a lot, use 0.25. There are more in the bottle for the same price, and you will hit the target with a few bursts. If you shoot on semi auto, use the heaviest BB your gun can handle. Bios are even more accurate because there are less or no air bubbles inside. Try G&G bio, those are not bad as far as I know. (I don't buy my bbs here so I haven't tested the brands available here.)

Fps-wise you are correct. The same guy who shot the video says that above 500 fps there is no more range gained, only the travel time is reduced. Heavier BBs do increase the range, but only very slightly, as seen on the link Mack put here. Don't get me wrong, I'm not trying to be a dick here. If you can shoot an A3 on 100m 10/9 and you have a proper video of it that'll be awesome, and I'll need to do something about my rifle.

Cool. Please measure that 100 meters (not feet, not steps). Write down your fps, gun setup, BBs too. Get someone or a camera next to the target to show the hits. This way this will be a fine reference. As far as I know, one can hit a chest sized target reliably on 70m with a good setup, so it will be interesting for me to see whether 100m is achievable. This is from a sniper I know and you can't really get better gun than the one he is using - note: in Hungary 600fps is allowed for snipers.

No offence, but it's an urban legend.

Be careful with britishmilitarysurplus. I've ordered an ubac from them, and it turned out that the sizing is way off. My chest is exactly 112cm so it's Extra Large according to their chart. However the XL ubac was gigantic. It took quite a few emails with photos to convince them to send me a new one if I return the big one. I still had to pay the return P&P. They said that it's not their fault if their supplier gives wrong size (according to their logic it's my fault.) Otherwise they sell good stuff but the customer service is not very customer oriented...

The full metal JGs are actually pretty good. If it does nothing at all, it is most probably electric. My first thought was that the motor contacts came off, but you say your buddy swapped the motor, so it must be something else. Have you checked the fuse?

Stick a thin piece of plastic or a few layers of duct tape in the back of the magwell. Something like this: http://imagizer.imageshack.us/scaled/medium/853/43sb.jpg It's not an M4 but you get the picture. This pushes the mag forward, so the feeding part moves up.

It's easy to do. Unscrew the bottom two screws, remove the bottom plate, take a good look where the wires are exactly. Pull the wires off the motor, pull the motor out. Unscrew the screws inside the grip, pull the grip off carefully. Put the new grip on, arrange the wires and put the motor in. Connect the wires, screw back the bottom plate. Now adjust the motor height. Without magazine or BBs, fire the gun. Be careful, there might be one BB left in the barrel. If you hear loud screeching and the gun doesn't fire, turn the motor height screw in, the motor doesn't reach the gears. Turn the motor height adjuster screw in, until the gears turn a bit slower or stop. That's too high. Lower the motor bit by bit, until you find the most quiet height. It is just below the "too high". If you lower it even further, the gun still fires, but the gears are louder, because they are connecting too loosely.

Change the gears, they tend to break. And I think it was G&P where the piston head cracked and then broke.

One of the M4's most problematic points is the magazine. Try with different ones. Also try yours pushing it back or front or up while firing.

http://www.wgcshop.com/ has Modify. Can't link from them. Search for "Modify Baton Ryusoku Hopup Bucking". Edit: ebairsoft has some brand I never heard of: http://www.ebairsoft.com/advanced_search_result.php?keywords=+G+X+HighTech+AEG+Hop+Up&inc_subcat=1&search_in_description=1&x=0&y=0

Don't reinvent the wheel. Especially if you don't have a lot of experience with it. These are at least two full time jobs: designing user interface and coding it. If you want a shop, use a ready made webshop engine, like opencart. Then pay a designer to create the unique design for your shop. If you just want to be present on the net, use facebook - and maybe if the shop is something special then pinterest, instagram, twitter, etc. There are many free papers on how to use those effectively to increase your sales. As a professional programmer I would say: only create new code if you can't find one already done. Creating and maintaining custom code is the most expensive way to do it.

Most probably something has changed around the trigger contact. Maybe the two copper contacts came a bit more apart, meaning the trigger needs to be pulled a bit more than before. In the G36 the hole in the grip for the trigger is not long enough to allow the trigger to fully move back. Check the trigger switch contacts or make the hole for the trigger a bit bigger.

If it's a hi-cap, wind it up some more. And more.

Is it a hi-cap? If you pull the small thing that holds the BBs in, does it spit the BBs in your eyes?

I'm with jcheeseright. Is it inaccurate or too weak? Then fix those parts. If it shoots fine, you have nothing to gain by replacing perfectly working parts with different parts with supposedly better quality but with slightly different sizing. If it happens to work fine, you'll get the same results as now. Go for external upgrades. Find the best sling, red dot, foregrip, stock, fastmag, etc, or paint it. There's a lot that can be done, without opening the gun. Edit: just read the 0.20. Use at least 0.25, or even heavier.

How strong is it now? IMO just change the spring and clean it. Real sword's barrel is fine, no need to get a TBB. It would only give you some fps but since you are changing the spring too, you can get the fps there.

It doesn't fit anyting else.

IMO you can use that setup in cqb just fine. If you want to go to a woodland site, I recommend an AEG. Pistols don't have the range and the needed capacity for that. Also for CQB I strongly recommend face (teeth) protection.

By correcting the AOE you need to cut the second and maybe the third tooth, keeping the first.

You can test the airseal between the GB and the hopup by plugging the hopup's bb feeding part (with your finger) and taking the end of the barrel in your mouth and blowing air in it. Best done with the GB and barrel removed from the gun. If not, it looks silly. Disengage the AR latch before doing it so the nozzle and the piston is in a forward position.

I don't know if there is a G&G compatible NPAS, but if there is, then that's the way to lower the fps.

On the real steel one (Benelli M3) it swithces between semi-automatic and pump-action modes.

Using bio BBs is not such a bad idea in my opinion. I'm no green at all but I use them instead of the never degrading ones. We pour quite a few bags of plastic on the airsoft fields each weekend. I think that adds up too fast.