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Executive Summary

Our group has continued work on the Well's L96 airsoft gun through research and brainstorming. Our research includes attending an airsoft game hosted by the Western Pennsylvania Airsoft community and seeing how well the L96 performs. Our observations led us to identify many problems with the L96 which in turn helped us to generate ideas for the gun's redesign. The biggest problem we discovered is that the magazine will misfeed BBs if the magazine is not completely put into the gun horizontally. This problem occurred so frequently that we decided it must be fixed in a redesign. Another problem we observed was that it was difficult to tell when the gun was low on ammo. This is a good problem to solve because this not only pertains to our gun, but is also a common problem among most airsoft guns. We propose redesigning the gun to include a digital counter that displays how much ammo is left in the magazine. In addition, we believe the gun scope should have an LED in it that turns on when the gun is low on ammo. This LED would know when to turn on because it would be hooked up to the ammo counter. Finally, we noticed the magazine for the L96 had to be reloaded often because it does not hold a lot of ammo. The magazine needs to be redesigned to increase the ammo carrying capacity.

Research and Observations

On September 30, 2007, our group went to an airsoft event hosted by the Western Pennsylvania Airsoft (WPA) community. The event took place at a secluded forest area known as Peaceful Springs. At this event, attendees played a few airsoft games in which opposing teams shot their guns at each other while trying to complete an objective such as capturing the opposing teams flag. All in all, there were about sixty people who attended this event. Our group went to this event in order to better understand the people who play it as well as to see how well the L96 performed.

Airsoft Players Observations

99% of all the players were male
Everybody wore military fatigues and camouflage
Age ranged from 15 - 40s, although the majority was 18 - 24
Most players had automatic electric guns (AEGs in airsoft terminology)
Most guns were replicas of assault rifles or submachine guns. There was a lot of gun variety
Some players carried pistols as secondary weapons
Everybody wore eye protection since it was required. Some people only had eye protection while others had a full face mask
Players liked to show off their guns to other players
Players accused other players of lying about whether or not they had been shot during a game
There was an incident where an eliminated player took off his eye protection while still in a dangerous area. People yelled at him to put it back on but he refused
Some players used walkie-talkies

L96 Observations

Carrying the gun through a forest area is tiring, but the gun sling helped alleviate the pain
Aiming the gun was difficult because the lens of our scope was too small
The magazine jammed several times during games
The gun had a longer range than the typical airsoft gun
Running out of ammo was a problem during games
Having to cock the bolt each time proved to be a competitive disadvantage
The gun is too long so much so that it makes it unwieldy
It was difficult to determine when the gun was low on ammo

WPA players from the airsoft event

The Design Problem

Our observations of the L96 show that there are many areas of this gun that could be fixed with a redesign. The most troubling issue with the gun was having the magazine jam on many occasions. There is no question that this needs to be fixed. The second most troubling issue was the gun was impossible to aim with because the scope was too small. That is actually our fault and not the designers because the scope we happened to have was not made for the purpose we used it for, and thus was too small to effectively use. A typical scope would have an objective lense size of about 32-50mm, but outs was 15mm, which made it hard to use, especially with a mask on. The other problems we had with the L96 are not actually design flaws, but are related to how realistic the gun is. For example, we found the gun to be too heavy, too long, and too slow to fire. However, the designers did not create the gun with these flaws because they are incompetent or cheap. They did this because the real L96 actually weighs a lot, is long, and is a bolt action weapon. Nevertheless, the L96 can be redesigned to fix some of these flaws even at the cost of making the gun a little less realistic. Realism means a lot to airsoft players, but gun functionality is also important as well. For many airsoft players, though, functionality will take some precedence over realism. For example, no real assault rifle can hold over 300 rounds easily, but many airsoft users would opt for an airsoft gun with a magazine that can hold that many rounds.

Design Ideas

The following is a list of ideas for the redesign of the L96. These ideas were created in an attempt to solve any of the problems we observed with the gun.

Idea #1 - Silent Gun

Airsoft players who buy sniper rifles expect their gun to behave like a sniper rifle. One feature common among some sniper rifles are that they are silenced. The L96 generates enough noise such that when it is fired, opponents may be able to pick up on a sniper's location. The main source of noise for the airsoft gun is the piston. The piston head generates significant noise when it hits the end of its casing. The other source of noise for this gun is the bolt as it is being cocked. This is especially troublesome during an airsoft game where the tendency of the user is to pull the bolt hard and quickly to get off as many shots as possible at opponents. Silencing this gun should allow the user to cock and fire the gun without being detected by the sound of his gun.

Idea #2 - Ammo Counter + Scope Indicator

Our research at an airsoft game showed one major problem with airsoft guns is that it is difficult to determine when a gun is low on ammo. One way to solve this problem is to digitally count the remaining BBs in a magazine and display that number on an electronic counter. We believe the ideal location for this counter would be behind the bolt so that the user may glance down at the counter while he is cocking the bolt. The user, however, might not always check the ammo counter before trying to shoot the gun. For that reason a red LED will be visible in the gun scope. The LED would turn on as a "NO AMMO warning" to the user, otherwise it would remain off. Although the idea is to use the LED as a "NO AMMO warning", other possible uses for the LED have been proposed such as using it to indicate whether or not the bolt is cocked or to indicate whether or not the safety is on.

Idea #3 - Custom Body

The L96 is an unwieldy gun. This can be improved on with a custom body that will reduce the gun's long 45" length and heavy 14 lb body. The length can be reduced by designing a collapsible, retractable, or foldable stock. Reducing the length would allow for greater maneuverability, as well as reducing the space it takes up when stored. The weight can be reduced relatively easily by taking out the metal weights that are in the stock of the gun. Another inclusion to a custom body that would improve the user friendliness of the gun is a built-in bipod.

Idea #4 - Spring-Electric Gearbox Hybrid

There are three kinds of airsoft guns: spring, electric gearbox, and gas guns. The L96 is a spring airsoft gun which means the user has to cock the gun each time he wants to fire it. While this works fine for targets at long distances, it is a tremendous disadvantage for airsoft players in a close quarters combat situation. Airsoft guns with electric gearboxes dominate in those situations because their gearboxes allows a high rate of fire (~10 BBs/sec). The L96 could be outfitted with an electric gearbox to serve as a secondary mode of fire made especially to help out in close quarters combat.

Idea #5 - Magazine Improvements

The current magazine operates with a load capacity of 25 pellets and is loaded into the Well L96 from the bottom of the gun. Problems that we encounter with this magazine setup are that the magazine might not load correctly; multiple pellet may enter the loading chamber if the gun is cocked more than once; also, the empty magazine indicator is not very visible and does not show how many rounds are left in the magazine.

Since there are many problems with the magazine, we agree that a complete redesign of the magazine assembly might be an alternative. Ideas to improve the loading of the magazine include chamfering the edge of the magazine or the edge of the socket so that a perpendicular entrance would be easier. Adding a guide rail between the magazine and the socket might be another option.

Another way to improving the magazine loading is to use magnets to connect the magazine to the socket. The connection between the magazine and the socket is envisioned as a flat plate. If the magnets on the magazine and the socket are arranged in an non-symmetrical fashion that mirrors each other, then the magazine will be forced to align itself upon entering the socket.

To prevent the loading of more than one pellet into the barrel, arranging the pellets so that they are linear and not stacked might be an option. If the pellets are linear, only one pellet can enter the loading chamber at a time as the pellet that is already in the chamber will block the entrance of a new pellet. With the stacked formation, the pellet may attempt wedge itself into the loading chamber if the gun is cocked twice.

To indicate the number of rounds left in the magazine, a LED counter similar to the one mentioned above may be added to the magazine. To let the user know that the magazine is empty, we can also devise a mechanism that will drop the magazine halfway out of the socket upon loading the last pellet. This added feature will make it more obvious that the magazine is empty than the current indicator.

Finally the current capacity of the magazine is 25 pellets. For ease of calculations, if we assume that the each pellet is cubic with a length of 6 mm, and that inside of the magazine is completely filled with pellets, then a theoretical max pellet count within the magazine should be approximately 270 rounds. This is an over estimation as the magazine case has some thickness and springs that take up space. Regardless, we believe than an magazine with an increased capacity without the increase bulk might be possible. Below are sketches of two packing formations that we are considering.

Comparison of Ideas

Pugh charts are handy tools that help design teams compare different design ideas as a whole. This Pugh chart compares the design ideas for the L96.

Pugh Chart

Criteria	Weight	Silent Gun	Ammo Counter + Scope Indicator	Custom Body	Hybrid	Magazine Improvements
Realism	2	0	-	- -	- -	0
Functionality	3	+	++	+	++	++
Safety	3	-	+	+	-	0
Affordable	1	0	-	-	-	-
Maintenance	2	0	-	0	-	0
Durability	2	0	0	0	-	0
+		3	9	6	6	6
0		7	2	2	0	9
-		3	5	5	12	1
Net Score		0	4	1	-6	5

According to the Gantt chart, the best design improvements to the gun are the ammo counter + scope indicator and magazine improvements. These improvements are valuable because they offer plenty of functionality without too many drawbacks. The hybrid idea also provided extra gun functionality, however, it is a low rated idea because it severely hurts the realism of the gun while also making the gun more expensive.

Final Idea Chosen

We finally chose to implement the ammo counter + scope indicator design as well as implementing the magazine improvement. The magazine improvement is a necessary redesign because it is something that should have been working right in the first place. It is a design flaw of such magnitude that it makes the gun unusable. Also, the magazine does not hold enough ammo. It is frustrating to have to reload the magazine during a game or to have to carry around a spare magazine. It is for those reasons that we believe the magazine improvement is absolutely essential. We also chose to do the ammo counter + scope indicator idea because many airsoft guns make it difficult to tell when the gun is low on ammo. While our magazine improvements will be relevant only to our L96, an ammo counter + scope indicator idea can be used on almost any airsoft gun. If our ammo counter is successful, we will have solved an airsoft problem that has been troubling airsoft players for a long time.

We originally thought we would make a hybrid gun because it would provide a lot of extra functionality. However, our Pugh chart showed us that while it is more functional, it really is not a good idea because it will make the gun cost more while making the gun less realistic.

Value Opportunity Analysis

A value opportunity analysis shows how valuable a product is to the end user. One may use a value opportunity analysis to compare an old design with a new one to determine whether a new design an improvement to an old design. A value opportunity analysis is broken down into seven components emotion, ergonomics, aesthetics, identity, impact, core technology, and quality. Each component make be broken down further into several sub-categories.

For our magazine clip, we are not very concerned with our user perception of aesthetics as the clip is hidden within the stock of the gun. The identity and emotion appeal are other area that we are not really concerned with as we do not expect our user to become mentally attached to the magazine clip.

Major improvements to of our redesign clip are in ergonomics and core technology. Our new magazine design received higher ratings in both these areas as the new improvements will be significant in these areas. A larger clip size makes the magazine more enabling as the user can fire more shots without a reload. Our new design is also more reliable as jamming will become a thing of the past with our linearly packing system. Finally, our new magazine will be easier to load with magnetic technology or a guide rail.

Areas in which our design might be worst than the original is in the quality and craftsmanship. Since Well, the manufacturer of the L96 have a complex and comprehensive manufacturing setup, we naturally assumed that their finished product will be superior in the quality and craftsmanship to our rapid prototyped or machined magazine.

Tentative Schedule

The Gantt chart shown below outlines our tentative schedule. Each group member has been assigned a set of tasks. Tasks that are marked as group are the responsibility of the entire group. As this schedule is tentative, adjustments will be made if necessary.

Airsoft gun redesign