Ken
Start with the MAX stroke (inner screw full counter clockwise). This is not the spring, it is the striking part of the hammer. Counter clockwise brings it in flush with the hammer giving you the longest striking distance. Preload is tightening the spring (clockwise) for more power. Fill pressure is what the gun guage is reading before the shot is taken. MAX fill pressure is what you pump the gun up to at the start. Minimum fill pressure is what the guage reads when you stop and refill the reservoir.
As the "fill pressure" increases (on any gun) it takes a stronger "hit" from the hammer to open the valve. As the pressure decreases with each shot, the hammer will open the valve more and yield a bigger blast of air, because it is easier to open at a lower pressure. After you reach the "mid-point" of fill pressure the hammer is striking the valve open to the max with each shot, but the air pressure is decreasing from use. This will cause the blast (feet/sec) to start decreasing. This is known as the typical "bell curve" all UNREGULATED guns will have. With a good tune, your feet/sec will increase for the first "third" of your shots, then level out for the middle "third", and decrease for the last "third.
Most mods on unregulated guns are a trade off between speed and number of shots, but the" bell curve" is a little steeper with maxing out the mods. This means your first few shots and your last few shots will be slower than the middle (peak) shots. There are different ways to correct or help this delima.
1) fill to a slightly lower "max" pressure, maybe 2800psi
2) stop shooting and refill at a slightly higher "minimum" pressure, maybe 1700 psi
This lowers the shot count but keeps the speed more consistant. As you become more comfortable with working on your gun the Bstaley mod will help flatten the curve and keep the shot count higher. Getting 800fps with Crosman 14.3 gr pellets is quite doable with the mods I have already mentioned.
Look up more "posts" on P-ROD tuning. Many have pictures of all the different steps. Videos are ok, but sometimes the posts have more information and simpler explanations. Don't give up. It's really not that hard. If all else fails, PM me and I'll give you my cell number and we can talk.
Start with the MAX stroke (inner screw full counter clockwise). This is not the spring, it is the striking part of the hammer. Counter clockwise brings it in flush with the hammer giving you the longest striking distance. Preload is tightening the spring (clockwise) for more power. Fill pressure is what the gun guage is reading before the shot is taken. MAX fill pressure is what you pump the gun up to at the start. Minimum fill pressure is what the guage reads when you stop and refill the reservoir.
As the "fill pressure" increases (on any gun) it takes a stronger "hit" from the hammer to open the valve. As the pressure decreases with each shot, the hammer will open the valve more and yield a bigger blast of air, because it is easier to open at a lower pressure. After you reach the "mid-point" of fill pressure the hammer is striking the valve open to the max with each shot, but the air pressure is decreasing from use. This will cause the blast (feet/sec) to start decreasing. This is known as the typical "bell curve" all UNREGULATED guns will have. With a good tune, your feet/sec will increase for the first "third" of your shots, then level out for the middle "third", and decrease for the last "third.
Most mods on unregulated guns are a trade off between speed and number of shots, but the" bell curve" is a little steeper with maxing out the mods. This means your first few shots and your last few shots will be slower than the middle (peak) shots. There are different ways to correct or help this delima.
1) fill to a slightly lower "max" pressure, maybe 2800psi
2) stop shooting and refill at a slightly higher "minimum" pressure, maybe 1700 psi
This lowers the shot count but keeps the speed more consistant. As you become more comfortable with working on your gun the Bstaley mod will help flatten the curve and keep the shot count higher. Getting 800fps with Crosman 14.3 gr pellets is quite doable with the mods I have already mentioned.
Look up more "posts" on P-ROD tuning. Many have pictures of all the different steps. Videos are ok, but sometimes the posts have more information and simpler explanations. Don't give up. It's really not that hard. If all else fails, PM me and I'll give you my cell number and we can talk.
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