What is the “best” hop up unit on the market? Everybody asks and everybody who has an opinion says that METAL is the way to go and no other ways since plastic units will break without warning.

Let us take a look at the evolution of the Hop Up Unit just for the M4 series since that is the most common.

Echo1USA m4 hop up unit

This is the current Echo1 2 piece hop up design that was created for the Tokyo Marui rifles long ago and it is still used in many M4 variants to this day. You may be wondering why do companies use a bad design? Well it is not a bad design at all.

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The 2 piece hop up design was developed to allow for a split upper design to mimic the real rifles that Tokyo Marui was copying. The control part of the unit will be in the upper receiver and the mag tube section, which joins the magazine, will be bolted into the lower receiver. This design was used and still used by M4’s from Tokyo Marui, Echo1, SRC, KWA, and JG and there will be players claiming the TM hop up unit is bad while using a KWA rifle which has just about the same unit. This dislike of the plastic hop up unit came from marketing and lack of research by the players.

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Later on the 1 piece hop up unit was developed during the introduction of the metal body kits in the early 2000’s. The downside of this new unit will be that the rifle must come apart in the “Hurricane method” and there is no more split design.

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With the idea of the metal body is stronger than the stock plastic why not make a metal hop up unit. Stronger is better right but there is not a huge advantage of using a metal hop up unit unless you are building a rifle from scratch. The plastic hop up units will rarely break just because of their material. From all my years on the tech bench I have seen only a handful of dented mag tubes of the plastic hop up unit and I have see the same amount of broken metal units. The metal units will break on the posts that hold the gears in place. This is a draw when you think about it. Temperature does come into play in the extremes but that is a small occurrence.

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New inventions for the Hop Up Units such as the MadBull Ultimate 3 in 1 unit were a great thing and fulfilled all the player requirements but it cost more and was “new” for the install and that caused players to dislike and persuade their friends not to buy due to their lacking skills. But being a metal hop up unit it was a great choice along with a few other options on the market.

So we see the trends of the market making metal hop up units in “stock” rifles and as “upgrade” options. Plastic hop up units are “garbage and junk” just because they are old and will break. I do not have a scientific break down of data and facts to show since it would be ignored but I have more than enough years to see a pattern of how the plastic units when install correctly will hold and and keep the balance inside the rifle which is never talked about. We are using Japanese based guns and their copies. The Japanese have purpose and reason for everything and I agree.
The plastic hop up unit will act as a buffer between the gearbox shell and metal barrel to absorb the piston striking shock and in turn of having them all pressed together it will allow a perfect seal. Remember the air seal is important from the nozzle and bucking and the hop up unit has a minor role in it.

So with a little info I have seen and I know a few others will agree lets look a the current trend of units which should be metal since that is the best, right?

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Wrong, still plastic. These are the current hop up units for the 2016 rifles; left to right, VFC, Krytac and Modify. The material is never brought up that it is plastic since that would cause a dislike but the new term is “rotary” making it cool and the way of the future since it was seen in a youtube video. It is not a new design but it is being forced onto people as the best choice.
This is a great example of how Airsoft Media is pushing products on the players and telling them what is good or bad since the players themselves are not taking the time to fully understand the product they are buying.

What are your thoughts on these Airsoft Hop Up Units? Comment below.

Written by Brian Holt