install side rail (from Cyma) for side lock mount rail.
I started with the metal body -- I wanted to drill three holes for the side rail. I attached the rail to the body with plastic straps (I have no idea what is the proper word to use), as shown below.
At this moment I wanted to remove the barrel and install the tightbore. I followed this video but it was incompatible...
I was very surprised to see that the original barrel in Cyma CM.028 did not have the notches and hole that are used to install the hop-up bucking, as you can see on the video. It was just put inside the hop-up chamber, along with the hop-up bucking! So I didn't install the tightbore. :(
I also had a lot of trouble with installing the mount for stock on the new body. One of the parts didn't fit inside the body. This is the troublesome part. I don't have any file at home so it required some work to make it fit. :(
I finally put everything together. I tested the replica today -- it does work, but I want to change this barrel anyway.
Did you ever wonder why cheap AEGs from China (Cyma, Both Elephant, Jin Gong, Galaxy) have higher muzzle velocities than AEGs from Japan or Taiwan (Tokyo Marui, Classic Army, G&G, G&P)?
For example, new Cyma's AK47 has muzzle velocity of 410-430 fps (the one I own has 290 fps) and costs at WGC Shop $138 while Tokyo Marui's AK47 has only around 270 fps and costs $287 (price for AEG with battery and charger, to be comparable with Cyma's replica). You can easily see that the TM is twice as expensive as the chinese Cyma.
Many people in Poland buy those replicas because they think they'll get good replica cheap. They think that the more fps the better replica. Well... they are wrong...
What does the high muzzle velocity mean? Nothing except that the BB leaves the barrel with high velocity. It doesn't imply the replica has high range. It doesn't mean it has good accurasy, either!
What determines the range and accuracy? Inner barrel and hop-up. If the inner barrel is precise and made well, all the BBs will be fired in exactly the same direction. What happens after they're shot depends on the quality of the hop-up, especially the hop-up bucking (rubber). If the hop-up rotates each BB the same way, they all have the same trajectory. The better hop-up action, the longer range and the steadier trajectory.
One of my favorite replicas is the MP5K PDW that has less than 260 fps but is really accurate, despite it's short barrel.
So why the chinese replicas are made to have so much fps? Because this is the only thing that is easily comparable between replicas. You can measure the muzzle velocity easily, but you can't measure and compare the range and accuracy of different replicas! And it's easier to put stronger power spring than to make entire mechanism more precise and airtight.
I am in some kind of airsoft article frenzy -- expect more articles to be posted this week. I strongly suggest subscribing to my RSS feed on the upper left corner of the blog.
I saw a review of Cyma's CM028 - AK47 replica. And I thought I must write here something, because the review is bullshit. But what to expect when the replica is reviewed by someone who sells them, not by someone who only uses replicas!
Around 2:12 the guy says the following:
Not only will bigger and more powerful battery increase the rate of fire (...), also increase the range and accuracy up to 5 to 10 per cent.
Come on! The only thing that changes when you supply 9.6 volt current instead of 8.4 volt is the engine speed. The engine revolves faster, the gears in gearbox revolve faster, the power spring gets compressed faster. But the energy delivered to the piston by the spring does not depend on how fast the spring was compressed! So no matter what battery you use, the amount of compressed air that will push the BB through the inner barrel remains the same.
Well... there may be one case when it isn't the same. If you connect 12V battery to stock replica, the engine may try to compress the spring when it didn't decompress itself fully. The engine may revolve so fast that the next gearbox work cycle will start before the piston reaches the cylinder head.
Yesterday I played an airsoft game with Pluton Egzekucyjny (a young ASG team from Żyrardów, the town I live in). The game took place in Adamów, in couple of abandoned buildings. They were used by PKP, polish national railroad company.
First of all, when I opened my car's trunk and the replica bag I noticed that my Cyma AK-47S has broken stock. When I bought it I was aware that the folding stock in every replica is very delicate and may be broken soon. This disallowed me to use the replica, because I couldn't separate the stock from the rest of the gun. Only one of those rings that attach the stock to the body was broken and I didn't have hex key to remove the other.
This was it -- one large hall, one three-story office building with two stairways and many entrances.
The hall inside.
The office building as seen from the inside of the hall.
The office building. Cool red paint on the walls and pink tiles in toilettes.
One of the stairways. Broken windows. I heard that one of the people almost fell out through this window. It looks as it is not high above the ground, but this photo was taken while standing on top floor.
The hall seen from the office building.
The office building seen from near the hall.
I had much fun, 'cause I played with my favorite replica - MP5K PDW. :D
This is the review of my Cyma AK-47S replika. I wrote it because I believe there is still some place on the internet for articles about cheap airsoft replicas. Cyma replicas are certainly the cheap ones. I'd say, they're on the second shelf, while the first shelf are Tokyo Marui, Classic Army and similar priced replicas.
I read a review written over a year ago, followed by long thread of replies on one of airsoft discussion forums. The thread author wrote:
I found the CYMA AK on airsplat some time ago, and believe me, I was as skeptical as you. (...) A less informed friend of mine who is getting into airsoft (...) bought one. I expected him to receive it and immediately be sorry with his purchase--surprisingly, it wasn't the case. Upon arriving for our game that day, he showed me the AK. I was shocked upon picking it up to discover how heavy it was--it felt like a real steel AK from the weight. Also, I was surprised to notice the gun was almost all metal--in fact, ALL metal except for the grip, handle and stock, which were shockingly decent feeling plastic. Then I figured, what the heck. It looks good but will shoot like crap. Not so! I was VERY surprised when I was hiding behind a tree about 40 feet away from my friend (...) when suddenly a barrage from his AK ripped through the branches and demolished me.
I won't agree that Cyma CM028 is able to break tree branches. Nevertheless, I agree that most of serious airsoft players year ago wouldn't consider purchasing Cyma's replicas. The manufacturer's name was known as a definition of poor quality.
But the replica I own is supposed to be cheaper copy of Tokyo Marui replica! It has metal gearbox, plastic body and metal hi-capacity magazine! With the replica you get the hi-cap mag, stick type 1,100 mAh battery (I got S version with folding stock) and a battery charger! This means, that you need only the replica, BBs and eye protection to have airsoft fun! Standard Tokyo Marui replica comes with low-cap magazine, with no battery or charger. The player had to buy battery and charge it somehow. This makes thisCyma replica a good bargain!
What about muzzle velocity? There are two generations of Cyma AK-47 replicas on market. Mine is from first generation, an exact copy o Tokyo Marui replica. It is supposed to have something around 290 fps on 0.2g BB. I use 0.23g BB, and had 266 fps on chronometer. The replicas from second generation are said to have 360-380 fps muzzle velocity. They still cost in Poland somewhere around $150. :D
The guy quoted at the beginning of my article is wrong. The replica has plastic body, and plastic (wood imitation) grips. They imitate wood really good, I must say...
The hopup is easily adjusted. The sight can be adjusted as well. One can adjust it to aim higher - in the real-steel version this was used for shooting long range. In airsoft I use this feature if I adjust the hopup for long range.
Here are two video reviews I found on YouTube. :)
This article will start "my replica reviews" series. :)
As I mentioned my new airsoft purchases, I bought one new replica. This is a good time to tell my blog's readers what I got.
So I bought Cyma AK47S and I must say that this was one of my best purchases. I paid 429 PLN which is equal to $150. It came in complete set with stick 1,100 mAh battery (NiMH) and (what is very important for me) 500 BBs hi-cap magazine.
I bought the AK47S because it has folded stock and stick battery. As I own also MP5K PDW, now I have 3 stick batteries.
As I thought, the replica is equivalent to Tokyo Marui and I hope that it'll last at least as long as TM do. I used 0.23 gram BBs and measured 266 fps muzzle velocity. This is equivalent to 280-290 fps on 0.20 g BB, the standard for stock TM replicas.
Addition: I wrote an article on Cyma CM028 (AK47) on one of my sites in polish, thought you might be interested.
