Written by Masada » 01 Feb 2013, 06:46

This is going to be my review of the 2012 version Viper Tech XM177E1. Last year I wrote a comparison between the version 1 Viper and the 2011 model which can be found here: http://www.vipertech.com.tw/news_txt.php?num=35. It has been a long process trying to get this in to the United States, but it was eventually possible. I’ll be going over every bit of this gun, along with what it took to import this thing.

First off, the importation. I bought the gun from CWI Airsoft in Taiwan in September of last year which they promptly shipped out to me through EMS shipping, which here in the States is then handled by the Postal Service. Now, I live in Texas, but apparently the route the Postal service takes when importing from the West is to go through California. Specifically the Los Angeles sort facility and customs office. For me, this raised red flags immediately; I knew that the Postal Service goes through every single package that has to enter customs and from reading past experiences that the people in this particular area are not the smartest, nor the kindest when it comes to airsoft replicas. At this point it’s pretty obvious that my package was held and not allowed into the country. I called and asked why, and the response was “the orange tip was not permanently attached to the gun”. Now I also know that CWI painted and glued the flash hider onto the gun before sending it off to me. I was also told on the phone that it was able to be removed by hand WITHOUT any tools. Hmmmm, without any tools you say? Then why are there dents in the flash hider where someone obviously jammed a screwdriver in and torqued it loose? Anyway, at least they do not send held items off to be destroyed like they used to, it was just sent back to CWI after about a month. CWI then promptly sent it back to me after they liberally re glued the flash hider: so much so that it took me a torch to get it off yesterday. Nonetheless the LA customs stopped it again, this time because “paint is not permanent enough”. Basically the idea that I got from them is that unless the barrel is one piece of orange plastic, it is illegal in their eyes. So, it was sent back once again, but by this time CWI had gotten their license to ship through UPS so guess what happened next. CWI shipped it out through UPS and I had the gun within a week. Never again will I use the Postal Service.

I have to admit, CWI airsoft has been extremely helpful through this whole thing. Their customer service is fantastic and they are extremely understanding of the whole situation. Sorry for this whole wall of text, but I feel anyone trying to import a GBB into the county needs to know what can happen. At least I got the gun in the end, some companies would not be so nice.


On to the gun. As I said before, this is a 2012 Viper Tech XM177E1, personally my favorite Vietnam Era weapon aside from the M653. Particularly this is a late version XM177E1 denoted by the fully fenced magwell, square bolt stop base, and the late version bolt stop. I’m not sure whether the metal stocks came on all E1’s, but I’ll be fine with the plastic one for now. When I was making decisions on which Vietnam Era gun to buy I considered the Bomber M653 as well, but now that I have this Viper in my hands I am truly glad I didn’t go for the Bomber.

I will be dividing this review up into four sections: receiver, fore-end, internals, and overall fit and finish.


The centerpiece of any AR-15 is the receiver, and this one is no exception. I have to admit this particular receiver is one of the nicest I have ever seen fitted to an airsoft rifle. It really is gorgeous. Every feature is beautifully machined and there are absolutely no signs of the manufacturing process that should not be present. The reason I say this is because on these older AR-15’s the forging line was always present around the whole of the receiver as these were mass produced on a fast timescale. Other than the forging line there are no marks what-so-ever, no defects, no tool marks, nothing. Unlike my 2011 which has many small defects throughout the receiver.


As with all of Viper Tech’s products the barrel is a one-piece, steel structure that is stiff as hell. The front sight is cast steel like all other Vipers as well, but the one on this gun has had the bayonet lug cut off to fit the characteristics of the original XM177E1’s. The flash hider and gas tube are also steel as is expected and the slim plastic hand guards feel just like guns from that period should. Overall, very impressive. But hey, it’s a Viper Tech, did you expect anything else?


The internals are the same design as the 2011 model before it, but everything just seems tighter and better made. The only exception is the barrel extension which has been modified from the 2011 to prevent jamming even more.

I’ll give a quick rundown of everything inside the receiver.

The trigger assembly is full hardened steel. The disconnector specifically is oil quenched steel to ensure an extremely long lifespan. I did notice that the hammer spring is not strong enough to fire MAPP gas like my 2011. I believe this is because the gun sat cocked for the last 5 months as that will surely cause this problem. I’ll get a new hammer spring and see if it fixes the problem.
Firing Block:
The GFPA ’11 provides more reliability and more consistency over a standard WA block. The firing pin is steel and even when the hammer is not cocked it allows you to insert a mag without problem. The bolt catch is steel and the retaining spring is much stronger than the one on my 2011. This created problems when using mags with weaker loading springs as they do not have enough force to push the bolt catch up. Simply removing or cutting down the retaining spring fixes this problem.
The carrier is steel while the nozzle is aluminum. Overall the weight is very high. The nozzle still implements Vipers dual o-ring design to improve sealing and gas efficiency. The bolt is still slightly short stroked to provide better performance and reliability.
Same as the 2011 design with the exception of the barrel extension as described earlier. The 2011 design employs the use of Vipers special hop up rubber that almost completely eliminates jamming while still providing great accuracy and range.

Overall performance is even better than my 2011. Since everything on this gun is tighter and the tolerances are closer it all just works better together. The result is crisper shooting, more recoil, and more gas efficiency.

Overall Fit and Finish:

This is what really surprised me about this gun. I was expecting it to be a little better than my 2011, but boy was I wrong. There is literally no wobble between the upper and lower receiver, no wobble in the grips, nothing. The only this that does move is the stock, but that is completely normal. It really is amazing. It makes the gun feel many times nicer than any previous gas airsoft AR-15 I have ever held, and it really does easily compare with more expensive real steel guns.
The finish on the receiver is something to behold. Viper Tech really did their research on these old guns. The finish is just the right color, a dark gray with a hint of green. The only real difference is that the Vipers receiver is anodized so it is a bit shinier than a real one, but still extremely nice.
Overall, fit and finish is fantastic. Leagues ahead of any other airsoft AR-15 I have ever seen.

Now time for some extra pictures. I wish I had a better camera, but this will have to do for now.

Next to the 2011 Viper:

Original Post : gasguns.info forum