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DSG barrel length and FPS

1015 Views 16 Replies 5 Participants Last post by  Leo Greer
I am currently working on building my first DSG and was curious if anyone else has run into this weird issue or can explain why what's happening.
I have almost identical fps on semi with a 168mm 6.01, 275mm 6.03, 325mm 6.01, and with a 416mm 6.03, all at around 360-375 fps (.20s)

Current Build:
SHS 18:1 DSG (8tooth)
G&G 18:1 Bevel & Spur
SHS swiss cheese piston (teeth cut off, 3rd tooth lightly shaved down, AOE corrected)
Lonex Aluminum Piston Head (bearings removed, spring guide has them)
Lonex Full cylinder
Lonex Cylinder Head (one with the pads at the front of the gearbox)
Retro Arms 8mm GB
SHS Meteorite bushings
Maxx 21.25 nozzle (2nd o-ring removed)
Tappet plate cut to 10mm (Not sure what brand but starts 2-3mm later than the long SHS tappet plate)
Strong tappet spring cut 3 coils
ASG 30k (not the fancy CNC)
Perun Hybrid (in DSG mode, no AB in semi, lvl 3 in full auto, no precock, no ROF control)
Maxx ME Pro Hop-up
R-hopped 6.03 275mm
G&G green (nub cut)

I am also still working on full auto fps loss with more powerful batteries,
7.4v 2200mah (25 or 35c, cant remember) shoots ~32ish rps at around 330-340fps
Titan 3000mah 11.1v (I believe 15c) shoots ~41ish rps also around 330fps
But my big 3000mah 50c has reached a high of 52rps on the chrono, but skips and misfeeds usually around 280fps, sometimes after a burst on full, the last bb will roll out of the barrel
Did I make my tappet too short? Is it still too long? Is my tappet spring too strong and pushing the bbs out of the hop into the barrel?

This only happens using the larger battery on full auto, semi still works great feeding and fps wise with the larger battery.
I was using a lonex m150 spring and believe I was hitting PME on full with the larger battery, tried a matrix m160, which bumped around 20fps or so using the 6.03 275mm (usual barrel I run with the gun) compared to the m150, putting me at around 375fps. This helped with the overspin using the larger battery and I plan to use a guarder sp150 when it arrives to further cut down overspin and hit my target fps.

I want to be at 400fps with .20s and will get a smaller barrel if need be, however when testing the smaller barrels, I still had the same fps. What is going on??? Am I under-volumed like crazy? Over-volumed somehow?

To note, I played with the DSG with the m150 and the 7.4v around 30rps and cycled 10k+ rounds with no wear on piston teeth, 11.1v big battery arrives, test in full auto (around 100-200 rounds or so) to see big drop in fps, open gear box and visible wear on the piston teeth. How strong of a spring do I need? I believe a Guarder SP150 should be plenty. Should I swap the aluminum piston head for a Lonex POM piston head? A gate EON POM piston head?
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You should not use Ion batteries, Titan power are 6C batteries that they put 15C on. It is a lie and a scam. If the other 11.1v lipo gave you 52RPS you should not use a battery that gives you much less. Go down in size until the you see RPS drop and don't go any smaller. 2200mah 11.1v should work fine and fit in some stocks. If you have FPS loss in auto it is probably tappet PME. Here is a picture of a SHS tappet that will cause major loss in FPS during auto vs a Guarder tappet. You can see the distance between the sector pickup and tappet after piston release is not enough using the SHS.(9tooth piston on 8tooth DSG)
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Just to be sure, what grease do you recommend for the gears, and what for cylinder/piston head o-ring & nozzle/cylinder head?
I use MolyKote33 on gears. Most use superlube on air seal parts. I use some paintball brand dow33 on air seal parts.
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