HNPD FAS 604

ZHEC

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Got this nicely boxed FAS 604 last week:LOL: — my first air pistol after receiving my AWC. It came with three weights but, sadly, no sight extension.

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This one appears to be a later version with a rounded top cover, rather than a sharp corner where cracks tend to develop on earlier models. I’d always thought this change only came with the FAS 6004… I was actually confused for a while and thought someone had swapped in a 6004 top lever, but I eventually found more photos online showing this rounded feature on later examples with serial numbers past 10,000. Hopefully this one will last longer, as I paid quite a sum for it.

1776444186107.webp


It has an adjustable palm shelf, but the grip is still too large for me, so I spent a few hours printing some customised palm shelves to get a somewhat better fit. Maybe I’ll print a whole grip someday when I’m in the mood for modelling (though that will probably never happen…).

1776444211357.webp


Next bit of tinkering was the sight extension. I modelled one based on the a few photo I found online, may not be an accurate replicate but it turned out to be a nice match. Solid enough and effectively takes the sight radius to about 13".

1776444235929.webp


Another thought came to mind later that day:unsure: why not hollow it out and add a few chambers? It might not be the most effective way to make a moderator, but it does seem to take the edge off the sharp crack a little. The first version looks like this below, 3D printed as a single piece, following the profile of a sight extension.


1776444800907.webp


To push it further, I expanded the chambers slightly in the horizontal direction to the width of lower frame. The overall volume is probably still smaller than the first chamber of a proper moderator, but it’s at least more useful than a dead-weight sight extension. Looks a bit ugly thoughHomer face palm.

1776444303361.webp

1776444321191.webp


It shoots 360ish with econ II and punches nicely at 6 yards and deadly accurate. Haven’t tried 10 meters but I’m quite happy for nowDancing banana
 
it would be a nice addition to the FAS 6004 but the dovetail is different as far as i know
I haven’t got a 6004, but I imagine it shouldn’t be too hard to model. Maybe I’ll get a 6004 one day as a daily shooter if a suitable one pops up, I don’t really want to abuse this lovely 604:LOL:.
 
Lovely looking later pistol, well done. And excellent work on the printed extension, looks perfect. The added baffles / spaces could be used to add weights if you wanted more muzzle weight. Personally I like the weight of the 604 as it is , but having the sight extension really does help with precision. HNPD
 
Lovely looking later pistol, well done. And excellent work on the printed extension, looks perfect. The added baffles / spaces could be used to add weights if you wanted more muzzle weight. Personally I like the weight of the 604 as it is , but having the sight extension really does help with precision. HNPD
I also prefer the it without any weight, so I’ve only used the lightest one to bolt the extension down.
 
HNPD! Lovely example and some very neat and well thought out additions!

A rattle can of black paint will blend the grey in nicely 👌
 
Btw, would you be up for printing any more? I might have a couple of 604’s that could benefit from the extra sight radius without having to swap the original I have round between them.
 
Btw, would you be up for printing any more? I might have a couple of 604’s that could benefit from the extra sight radius without having to swap the original I have round between them.
I certainly will, this is still an experimental model so I’m just using the grey filament left on my printer. They’ll be in black or another preferred colour afterwards. I'll DM you once I've finalised the design.
 
I certainly will, this is still an experimental model so I’m just using the grey filament left on my printer. They’ll be in black or another preferred colour afterwards. I'll DM you once I've finalised the design.
I can think that there will be quite a few requests for these, thanks.
 
Got this nicely boxed FAS 604 last week:LOL: — my first air pistol after receiving my AWC. It came with three weights but, sadly, no sight extension.

View attachment 958994

This one appears to be a later version with a rounded top cover, rather than a sharp corner where cracks tend to develop on earlier models. I’d always thought this change only came with the FAS 6004… I was actually confused for a while and thought someone had swapped in a 6004 top lever, but I eventually found more photos online showing this rounded feature on later examples with serial numbers past 10,000. Hopefully this one will last longer, as I paid quite a sum for it.

View attachment 958995

It has an adjustable palm shelf, but the grip is still too large for me, so I spent a few hours printing some customised palm shelves to get a somewhat better fit. Maybe I’ll print a whole grip someday when I’m in the mood for modelling (though that will probably never happen…).

View attachment 958996

Next bit of tinkering was the sight extension. I modelled one based on the a few photo I found online, may not be an accurate replicate but it turned out to be a nice match. Solid enough and effectively takes the sight radius to about 13".

View attachment 958997

Another thought came to mind later that day:unsure: why not hollow it out and add a few chambers? It might not be the most effective way to make a moderator, but it does seem to take the edge off the sharp crack a little. The first version looks like this below, 3D printed as a single piece, following the profile of a sight extension.


View attachment 959012

To push it further, I expanded the chambers slightly in the horizontal direction to the width of lower frame. The overall volume is probably still smaller than the first chamber of a proper moderator, but it’s at least more useful than a dead-weight sight extension. Looks a bit ugly thoughHomer face palm.

View attachment 959001
View attachment 959002

It shoots 360ish with econ II and punches nicely at 6 yards and deadly accurate. Haven’t tried 10 meters but I’m quite happy for nowDancing banana
Happy new pistol day! Great idea to include a moderator in the sight extension -great use for a 3d printer
 
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