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Sitting Duck

Increasing tappet plate travel mod ......

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Hmmm well ergh still not done to lots of guns but so far it hasn't made stuff any worse

a bit of pi$$ balling about but allows tappet travel to increase

and stop the risk of them bending/breaking if they bottom out on cylinder head standard position.....

(This for a v2 gearbox btw, shouldn't really need this for v3 but same meat different gravy if really needed)









This is just one of various bits n bobs I've been playing with

yes cylinder head is a bit short and 1mm less required to correct AoE etc....

but with a delay clip it pulls back the tappet and with this increased travel improves the chances of feeding better on full auto


you may need to pay close attention and shave the back of tappet fin from hitting the spur gear's spindle etc....

but the v2 box total travel is crap compared to many v3's

hopefully it will help increase the travel from about 8mm max to nearly 9.25 - 9.5mm

if bb's still don't feed then you gotta be using wrong nozzle or something else

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Why do you need that? Are you using bigger than 6mm bbs? :)


needed to try heavier ammo - could find decent .40's so now using golf balls - love the whiizzzzzzz they make


nah - it is sometimes you find "some" tappets bottoming out, bending - even breaking where they have slammed against cylinder head, delayer keeps it pull back a bit longer, some delay clips pull it back a bit further. Plus found SHS tappets seem to retract further than other stock ones - quickly promoting wear at the fin if no damage occurs due to usual perfect 101% TM compatible parts crap etc.......


Some gearboxes are different too - Had 3 x D-Boys v2 boxes and they may have varied ever so slightly different

(some had 4 pistol grip m3 holes, another just usual two, one or two had cut outs for AR Latch & even cut-outs showing bevel gear)

They all had the front of gearbox showing up as 2.65mm thickness where most other makes were 3.1mm or there abouts

This must have an effect on how much the nozzle protrudes through into hop as 0.5mm can make the difference between nozzle clearing to chamber bb but still seal nicely on bucking...

Normally you get about 8mm max total tappet retraction which sounds plenty for a 6mm (5.95mm) bb to pass, but depends on nozzle length - even the actual shape as some are flatter or more tapered plus the new crap on the join in centre to assist pushing bb through bucking to nub area

Yes there are mods n stuff but I prefer to use correct nozzle and not file down if still not feeding - one the finish may be ultra smooth, risk of taking too much off and also risk of filing it pi$$ed if done badly for better feed but fps loss on seal

(obviously doing anything properly takes a little time - I'd probably put nozzle in drill set all true and then sand her down tiny bit by bit to attain smooth true reduction - or something like that perhaps if I had to)


Phew - Reason being I found that some tappets & some delayers draw back a smidge too far with some heads etc.....

Then I noticed the end of cylinder head though sitting flush with cylinder has the lower cylinder guide - the red/blue marks about 1 to 1.5mm further back

So the cylinder head could push back a little further to that mark, tappet travel increases and tappet doesn't bend up or wear away very quickly

Sounds daft to let the tappet fin wear away a possible 0.5mm to 1mm extra travel when it could be put to use drawing nozzle back a little further at higher speeds say


Looking around a few years back somebody tried this mod but at time they thought it was more for additional impact resistance

Which they was told/decided to just use neoprene/sorbo on cylinder head radius corners etc.... and that is all you can really do (light piston perhaps)


Well - like I say it was one of a few things I'm trying to play around with as I feel it should help

in fact dunno why cylinder heads have at least 0.5mm extra material at front or so

then you could shave the cylinder a smidge to let tappet come back a tiny bit further if bottoming out to assist feeding perhaps


Ah well, just some crap I've been messing with

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Just be aware that the cylinders rotate slowly if the Cylinder head isn't attached firmly. Double oring heads or glue should stop it happening, but without, you may get wear on the tappet from the cylinder trying to rotate into it.

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