I will explain the duties involved in configuring and tuning your LP Spyder in this article. These are crucial aspects of making sure everything runs properly when spending the time and money to convert your Spyder to a low pressure marker. I quite frequently see some people asking others what spring combinations and settings they use. Duplicating what spring combinations and settings others have in their markers, could take you way off what's best for your LP Spyder for the mere fact that not all of us have chosen to do the exact same mods and install the exact same components. Having different bolts, regs, valves, modifications and air supply can make a world of difference in the final tuning results we all may achieve, not to mention the difference in tolerances from marker to marker since Spyders and even other types of markers don't adhere to any type of specifically close tolerances.

CONFIGURING YOUR LP SPYDER

When converting to Low Pressure the most important components that are needed would be a high flowing regulator and high flowing valve. If you scrimp on quality or flow capacity of these particular components, chances are you'll yield minimal results. Springs and the combination used are very important as well. Don't expect a particularly great result from that $5 valve and $20 regulator that seemed like such a great deal when you bought it. Those will most likely end up in your spare parts box collecting dust after you realize that you got little benefit from them and in most cases, you get what you pay for. Having to run your marker at much higher pressures than others or the continual jack hammering when trying to attain a nice low pressure isn't normally what someone is aiming for when going through all of the work involved with converting to low pressure.

Opening up internal passages on your Spyder is particularly important because LP is based on a high volume of pressure flowing through the marker at a lower pressure than is normally used. Some people confuse the term 'low pressure' with 'less pressure' which isn't necessarily true. If not properly tuned it can become a total gas hog due to the high volume of pressure being pushed through the marker. Opening internal passages would consist of drilling and/or dremeling the existing vertical adapter passages, drilling the bottom line air supply adapter holes larger, removing/drilling the venturi from any particular type of bolt that you are using and some even go as far as drilling the ends of the pressure line larger. You could even get one of the longer aftermarket low pressure chambers/volumizers and drill it out for extra reserve pressure ready to feed the valve.

Polishing the internals is another modification that can be performed to add a performance edge to your LP Spyder. This involves removing the anodizing from the bolt and striker surfaces that mate with the inner upper and lower body tubes. This can be accomplished by simply sanding these surfaces until the bare metal is exposed. Starting with a lower 400 grit paper and changing to a higher 1000 grit paper when the raw metal is exposed is a practical way to go about this. After all surfaces are to raw metal, using a good metal polish is suggested for the final polishing. I would not suggest trying to polish the inner diameters of the upper and lower tubes. The surfaces are difficult to get to and if you mess it up you'll need to purchase an expensive new body for it.

You really don't need to purchase a lot of expensive aftermarket parts to make yourself a fine running LP Spyder. Buying a good quality reg, valve and a spring kit with a good choice of different spring gauges should do it for the cost factor. You'll get just as good a result from modifying the stock parts with a little knowledge of what you're actually aiming for. I've seen quite a few aftermarket delrin bolts and some lighter material strikers on the market and they just don't seem to work out on Spyders so well.  The strikers have bad wear properties and the gain you get from their light weight, you lose in a lack of dwell exerted by them. The delrin bolts are light but not having o-rings on them creates blowby so they're continually losing pressure from around them rather than directing the pressure specifically through the bolt.

TUNING YOUR LP SPYDER

You can have all of the most expensive parts in existence on your LP Spyder but if you have no idea of what you're doing and why, you may find yourself asking why did you even attempt it in the first place because the results was terrible. If your only goal is to have the lowest pressure on the block, you're only kidding yourself of what a low pressure Spyder is actually about. Lower is not always better. Someone could brag that their Spyder can recock at 200psi or less but if they're shooting paintballs at 200psi, the velocity is probably at 150fps and the efficiency could possibly be terrible. I've found that shooting within the range of 300-400psi will get you a decent velocity and good efficiency from a low pressure Spyder. What you should be aiming for is a marker that can achieve the velocities that you seek, shoots smoother with much less recoil, has less a chance of chopping and is a bit quieter than when in the stock state. How do we achieve this sweet spot velocity and efficiency? Through the proper combination of parts, mods and tuning.

You can make tuning your Spyder simple and just be satisfied with what you have or get a bit technical and seek perfection. Tuning is specifically finding what pressure and spring combination gets the marker the highest velocity and best efficiency. As I stated earlier, all markers are individual cases when it comes to tuning. You will need a chronograph and a full tank when tuning. The chronograph part isn't so tough but the continual full tank may be. If you have the option you may consider having a few full tanks available.

The best way to go about changing springs out is to leave one particular weight spring for the valve and change the striker springs as you go along since they are much easier to remove and replace. You will want to document the findings so it will be much easier to recall what the best results were. I use an average of 3 - 5 shots. If you feel like getting more technical with the average you might average 10 shots. Below is a mock-up of what your final written findings might look like after the velocities have been averaged out.

lt vlv - lt strkr - 300psi @ 270fps
lt vlv - med strkr - 320psi @ 287fps
lt vlv - hvy strkr - 360psi @ 289fps

med vlv - lt strkr - 290psi @ 265fps
med vlv - med strkr - 300psi @ 276fps
med vlv - hvy strkr - 400psi @ 290fps

hvy vlv - hvy strkr - 350psi @ 279fps
hvy vlv - med strkr - 340psi @ 269fps
hvy vlv - lt strkr - 300psi @ 291fps

Start out with a light valve and light striker spring for example. With the velocity adjuster locked half way out and using no paint at this time, shoot a few shots and turn the regulator down a little at a time until it starts to jackhammer. You must take a few shots in between reducing the pressure in segments to let the regulator pressure stabilize. Once it starts to jackhammer, turn the regulator pressure up slightly until it shoots consistantly without jackhammering. Now take some fast shots to be sure that it doesn't jackhammer any more and there will not be any problems with shooting at a high rate of fire. Mark that spring combination and pressure down on your list. 

It's time to check the velocity in its current condition with some paint. Making sure that you have a good paint to barrel match will make your statistics much more accurate. Take about 5 balls from the bag and insert one ball at a time in the breech end of the barrel and manually blow it through. If the ball just rolls through when you insert it, the paint is too small for the barrel. If it gets stuck in the barrel and you can't blow it through, it's too big for the barrel. If it blows through fairly easy, it's a perfect match. Let's check the velocity now. Shooting one ball at a time, jot the velocity down between each shot on another piece of paper. When done with your list add them all up then divide that number by the number of shots you took. This will be your average velocity at that pressure and you can now add that number to the spring combination and pressure reading on your master list. Make sure that you don't deviate in the amount of shots taken with the different spring combinations when averaging these statistics.

Find what pressure you need to be at to achieve the final velocity that you seek by using the regulator to increase the velocity. Remember to take a few shots while between increasing the pressure in segments to let the regulator pressure stabilize. Once you hit the desired velocity you can do a shot average as you did previously. You can make a second list with these statistics as the final result for the desired velocity with that particular spring combination.

All that's left after you've made your list(s) is to choose which spring combination you think would be most practical and efficient. You cannot base efficiency by dry firing your Spyder. You'll get many more shots from a tank with backpressure from shooting a ball than dry firing your Spyder. You must use paint and you'll most likely need to do that on the field. If you have a 50lb fill station and a couple of cases of paint to spare, you could test it right there.

 FINAL THOUGHTS

You can spend a lot of time tricking and tuning your Spyder properly or just throw everything together and hope for the best. If you choose to spend some time and make things right, you'll need to research and thoroughly understand what and why you're doing these things that I've outlined here. If you take a trip somewhere in your car and don't know how to get there and why you're going in the first place, chances you're going to get lost somewhere and the trip will be a total waste of your time. Chances are you'll get the same results if you don't know what you're doing when converting your Spyder to low pressure. Research what you're doing and why and I'm quite sure that you'll be more than happy with the final results of converting your Spyder to low pressure.

The results you can achieve from converting to low pressure are very rewarding if done in the correct manner. It can convert that clanging, jarring, loud Spyder you started out with to a smooth running, accurate, efficient and quiet Spyder. It can be a great learning experience as well.

Technical Information