GBB Pistol Upgrade Guide: Umarex/VFC Glock GBB Series
Umarex / VFC Glock Series Upgrades
If you are lucky enough to have a Umarex / VFC Glock GBB pistol as your sidearm for Airsoft skirmishing you are well equipped to say the least, but if you want a performance improvement to help your Glock keep up with the other popular platforms on the skirmish field, this guide will be a useful read.
The pistols of the Umarex / VFC Glock series are full licenced replicas of the real Austrian Glock series of handguns which have become popular around the world thanks to their forward-thinking and unconventional design which is slowly managing to win even the Americans over to the European school of thinking on firearms design.
Respectable though it's out of the box performance may be, if you want your Umarex Glock shooting as nicely as it looks, a few upgrade parts would only benefit this fantastic platform and allow you to hone your Glock to your own specific requirements, whether you compete in IPSC competitions, on the skirmish field, or you just enjoy opening fire on targets in the garden.
Upgrades aren't generally necessary out of the box, we always recommend that you first use your pistol and highlight the areas in which you want to see improvements. If you are already there, give this guide a read and hopefully, you will leave with the knowledge you need to upgrade your Glock to perfection!
Slide Speed Upgrade
Under normal circumstances, the best upgrade you can add to your Airsoft GBB pistol to improve its cyclic rate is an aftermarket lightweight slide kit. Since in the case of a Umarex Glock, your slide is engraved with licenced Glock trademarks we assume you aren't too keen on replacing it and losing all that realism and detail, and as such, we recommend an upgraded recoil spring and guide rod as the first port of call.
CowCow Stainless Steel Guide Rod Set Gen 4 / Gen 5
The Stainless Steel Guide Rod set from CowCow is intended to replace the recoil rod and spring inside your Umarex/VFC Glock 17 with a reinforced stainless steel guide rod and an enhanced recoil spring. This recoil rod matches the Umarex Glock 17 and the real Glock looks perfectly with its dual spring design staying faithful to that of the real pistol.
The Stainless Steel Guide Rod Set is available for both the Gen.4 Glock 17 and the Gen.5, so make sure you get the correct set for your specific model of Glock. The recoil springs of the CowCow set are a step up in strength when compared to the original springs, and should allow the slide to return to battery more quickly, ready for the next shot. The set also includes 4 of CowCow's competition recoil buffers which can be installed in order to reduce the impact of the slide cycling on the internals of the pistol or to short-stroke the slide for a rate of fire increase. If you like a more realistic experience we recommend a single recoil buffer, but if you are all about speed and don't mind sacrificing the "slide lock" function of your Glock you can always add more buffers to get that beastly rate of fire.
Reliability and Longevity Upgrades
If you are getting some use out of your Umarex Glock, especially if it is upgraded already, we recommend adding some longevity upgrades either to stay ahead of parts failures or to replace your internal components as they wear with extensive use over time. These parts will allow for longer lasting performance and should also provide an improvement in trigger feel if you choose to add the CowCow Stainless Steel Hammer Set.
CowCow Stainless Steel Hammer Set
The CowCow Technologies Stainless Steel Hammer Set includes the hammer, sear, firing pin, rotor and rotor spring, providing everything you need to upgrade your hammer group with precise stainless steel components for improved longevity under heavy use. Each part of the set is polished to reduce friction using MAP polishing technology and is constructed from stainless steel to prevent warping under hard use.
Installing steel parts incrementally can often cause other parts in the pistol to fail prematurely, and as such CowCow offers the complete hammer group as a set so you can install all of the parts together. Installing this set into your Umarex Glock will provide an improved trigger feel with more precise engagement and a more noticeable reset and "wall", and will also allow for use with stronger gasses and other steel parts. If you are installing a steel slide or you are using red gas, or even if you put your Glock through heavy, normal use, you will benefit from installing this reinforced hammer set.
CowCow Stainless Steel Hammer Housing
This stainless steel hammer housing from CowCow is intended to provide the strength needed to work well with a strengthened hammer spring or a stainless steel hammer. This part is flawlessly machined from stainless steel using CNC processes to maintain the tight tolerances necessary for a precision part, and can also help improve the smoothness of the slide and hammer movement. If you have upgraded your hammer or other parts in the hammer group for use with stronger gas then adding this part is a must to keep your pistol running under the additional strain of higher pressure gasses.
Accuracy and Range Upgrades
Maple Leaf Crazy Jet Inner Barrel
Installing a Maple Leaf Crazy Jet into your Airsoft GBB pistol is one of the most effective upgrades possible, especially when coupled with an aftermarket HOP-up rubber. The principle behind this barrel's design is to provide an ultra stable air cushion surrounding the BB for the entire duration of its journey down the barrel, to prevent the BB from impacting the sides of the barrel which can cause fliers and accuracy issues, even in tight bore barrel setups.
This is known as the "wide bore" principle, which is intended to provide similar performance to tight bore inner barrels whilst minimising the chances of jams, and reducing the frequency of necessary barrel cleaning. The Maple Leaf Crazy Jet takes this principle, and runs with it, adding their own innovation to the idea of a "wide bore" barrel with the "jet stream" system, which ensures that the BB also exits the barrel without making contact, ensuring you get a stable trajectory with minimal fliers.
Maple Leaf 6.02mm Tightbore Inner barrel
The inner barrel is constructed from stainless steel and has a high polished internal surface for minimal friction, and a deep and smooth crown to ensure your BB leaves the barrel smoothly and consistently. This barrel is cut for either VSR/GBB style HOP buckings or Maple Leaf Hybrid buckings when used in an AEG.
This inner barrel is a great choice if you are on a tight budget, and is only marginally less effective than the Crazy Jet or Modify inner barrel when it comes to performance. If your Glock is to remain a sidearm and is used in emergencies only, this tightbore should provide enough accuracy to outdo any un-upgraded sidearm and keep you ahead in game.
Modify Stainless Steel 6.03mm Precision Barrel
The Modify Stainless Steel inner barrel was chosen for this guide for its rigidity and flawless internal finish, both of which contribute immensely to the performance of this aftermarket upgraded barrel. The barrel is constructed from high quality 304 Stainless steel, which offers both precise dimensions and less flex when compared to a brass or aluminium inner barrel.
The Modify barrel is regularly chosen over options such as the Crazy Jet for setups which lean into accuracy more than range, such as those used by IPSC competition shooters. If you are a CQB player who wants to be able to hit the enemy's fingertip at 10 meters every time, and you won't be needing the additional range the Maple Leaf Crazy Jet will provide, the Modify Stainless Steel barrel is the right choice for your build.
Maple Leaf Super Hop Rubber 50 Degree
The maple Leaf Super Hop Rubber is designed to provide additional range when compared to other Maple Leaf buckings and has a wide diamond-shaped contact patch which provides a significantly stronger HOP-up effect. We recommend the Super for those who want the longest range possible from their sidearm and would be a great choice for a sniper's backup weapon.
The range improvement provided by the Super outdoes even the fantastic Maple Leaf Decepticon and Wonder HOP-up buckings, but loses out slightly in the accuracy department as a tradeoff for the extra range. As with other Maple Leaf buckings, the Super is designed to ensure each BB is chambered consistently every time, and installation of this bucking will improve both the range and accuracy when compared to the original HOP-up bucking. If you are looking for an all-rounder of a HOP-up bucking with equal emphasis on accuracy and range, check out the following two options:
Maple Leaf Decepticon Rubber 50 Degree
The external surface of the Decepticon Bucking is ribbed to keep your inner barrel more stable inside your HOP-up unit and ensure you get a good air seal with no wasted gas. The contact patch inside is wider and longer than those normally found on GBB HOP-up buckings, granting greater stability and a stronger overall HOP effect.
This translates to longer range, and better accuracy when used with high quality heavy BBs, and improves the accuracy potential of almost any GBB pistol in both short and long range engagements. The Decepticon builds on Maple Leaf's superb Autobot bucking by providing a flatter contact patch for "flat HOP" like performance.
Laylax Nine Ball VSR-10 Hop Rubber
The Nine Ball Purple bucking has been known to be one of the best options for upgrading an Airsoft GBB pistol for pure accuracy, thanks to its high quality construction and superb brand pedigree. The manufacturer, Nine Ball, also known as Laylax, Prometheus, and First Factory, is one of the original Japanese manufacturers of Airsoft upgrade parts, and their expertise goes without saying.
The way the internal wall of the Purple HOP-up bucking has been moulded will guarantee an excellent air seal and reduce power loss, helping to stabilise each consecutive shot. We have been so impressed with the performance of this HOP-up bucking that the Bolster Armouries Tech Team decided that this is their bucking of choice for the incredible Bolster Armouries Hi-capa series, the second batch of which is already in production!
With this newfound knowledge under your belt, you should find yourself in a good spot to decide which upgrade parts your Umarex Glock is crying out for to get the performance you need to compete on the field. This article is aimed at owners of the Umarex/VFC series of gas blowback pistols, if you were looking for a guide on EU series pistols, you will find that right here.
If your Umarex Glock is primarily a sidearm, you might not need any upgrades, but if you use your Glock as a primary for CQB you may find yourself in a tough spot coming up against upgraded Hi-capa GBBs finding their way into more and more skirmishers' loadouts.
Whilst there may be more options for the Hi-capa, your Glock can still be made to perform superbly, and with appropriate skill and practice, you will still be able to tangle with the Hi-capa boi's and show them who is boss!