Springs
There are a lot of airsoft springs that are available in the market today. They are often coded or named with numbers that often leave buyers confused… Not to mention a each manufacturer have a different code for a spring for a given rating. Anyway here is a guide to help buyers to choose which spring to buy and an expected FPS output after the spring has settled (usually after a hundred cycles an airsoft spring settles and maintains a certain fps output till it eventually wears out)
|
Stage |
Spring |
Approx. FPS with settled spring using .20g BB |
Remarks |
|
Stock Gun (brand new gun) |
stock |
270-290 FPS |
Approx. FPS may vary with manufacturer or brand |
|
Stage1 Upgrade |
M100 / SP100 / PDI120% |
330-350 FPS |
|
|
Stage2 Upgrade |
M120 / SP120 / PDI170% |
390-410 FPS |
Still stable with .20 g BB |
|
Stage3-Upgrade |
M130 / SP130 / PDI190% / PDI210% |
440-460 FPS |
Still ok with .20g BB but is more stable with .23g BB |
|
Stage4-Upgrade |
M140 / SP140 / PDI240% |
470-490 FPS |
Ok with .23g BB but more stable using .25g BB |
|
Stage5-Upgrade |
M150 / SP150 / PDI270% |
510-530FPS |
Acceptable with .25g BB but more accurate with .28g BB |
|
Stage6-Upgrade |
M160 / SP160 |
550-580 FPS |
.30g-.36g BB are recommended for better accuracy |
|
Stage7-Upgrade |
M170 / SP170 |
580-600+ FPS |
.36-.4g BB are recommended for better accuracy |
Note:
Accuracy troubleshooting in terms of BB weight
BB hits everything but the target
Cause:BB too light for the FPS rating
BB drop without reaching expected range
Cause:BB too heavy for your guns power rating