Since there have been so many different opinions on the drive springs about whether they are effective or how they affect the marker's velocity, I thought it was pertinent to do a test of the various spring kits available on the market.
So let's begin with a review of how the marker works. Please read the opening section from the following thread:
Comprehensive Front Bolt and Powertube Test
Now by changing the tension of the drive spring, it will affect how hard the hammer hits the valve pin and results in a change of velocity. A weaker tension will give less volume per shot while stronger springs will give more volume. The pressure remains constant and is unaffected by the drive springs.
There are 3 spring kits that are commonly available:
Here is the setup I used:
1. Newer style A5 receivers w/ Cyclone/RT ports and polished internals
2. Metadyne folding stock
3. Freak back and 12" freak front using the Reball insert
5. Stock powertube w/ FVA flushed
6. Orange Howitzer front bolt
7. X7 valve
8. AKA 2-Liter Plus Dual regulator w/ HP spring and 7/8" extender cap
9. Braided stainless steel hose
10. CP direct mount on/off ASA
11. 32 degrees remote line w/ Lapco slide check
12. 68/4500 Pure Energy HPA tank
I started off by lubing up the marker and dry firing it before attaching the barrel. I then chronoed the marker with the stock spring close to 280 fps as a baseline to compare the kits to. Any change will let us know how the different springs will compare to a stock spring in realistic terms. The pressure is unknown but due to a lack of a pressure gauge but this is ensure as consistent a setup as possible. Adding a gauge cap on this regulator causes major problems and could have affected the results. The pressure is unimportant for this test since it will be kept constant.
If you read the previously linked thread, you can read the rest of my setup, measures I take to maintain as little fluctuation in results to external factors as possible, and how to understand the data.
The stock spring and Maddmann kit were used and broken in. Using the springs may affect how they perform if compared to new springs. The BT and Trinity springs, however, are brand new or barely used.
Now that's out of the way, let's take a look at the data:
As you can see, most of the springs in the kits are weaker than the stock spring. In fact, the only spring that gave a higher velocity than the stock spring was the Maddmann Red spring.
If you look at the section titled Kit Characteristics, it looks at each kit as a whole and compares them to one another. The Maddmann and Trinity kits are relatively the same in their mean velocities but I believe if the Maddmann kit were brand new, its average mean velocity would have been larger than the Trinity kit. The BT kit was obviously the weakest of the bunch.
The Trinity kit has a lower overall range of velocities than both of the others. The Maddmann and BT kits give the largest range of adjustments to the user with about 7 fps from high to low.
The Trinity kit has the smallest incremental jump in velocity from spring to spring while BT was larger and Maddmann with the largest. This means that if you change springs, the larger the velocity increment, the larger your velocity will change per spring. Smaller increments are great for fine tuning while larger increments are better for making large changes, such as people with velocity issues.
1. A good kit should offer a large range of velocities to adjust from. This gives players the ability to make big changes without altering anything else on their gun.
2. Overall spring tension is only important to the goal you want to achieve. Since different people have different needs, one cannot say that a higher or lower spring tension is better.
3. Due to the amount of velocity fluctuations that paintballs can produce, larger velocity increments between springs is better. There are better methods to fine tune a marker. Instead, drive springs should be changed out when large increments are prefered.
4. Kits should offer tensions both above and below the stock drive spring. Manufacturers should give users the option to change in either direction to assist their needs.
I'd like to thank Reeko61 from the A5OG for buying and donating the BT kit used in this test. Without it, we wouldn't have this valuable information.
Edited by Lord Odin, 29 June 2009 - 09:56 PM.