FAS re-seal

[Benelli B76]

Just put new seals in a FAS SSP for a local friend.Problem mainly was the tiny hidden O ring which seals the valve shaft, but I replaced all the seals as they cost me only 50p for all six. Tried to think of a way to hold the tiny aluminium valve so I could punch out the steel pin with no damage. I ground the shape of the valve in and old plastic screwdriver bit holder and put it in a vice. This stopped the round valve rolling around and I used a hollow tip starter punch to get the hard steel little pin moving, no problem. The hidden seal was quite badly worn, see pic. I have never been keen on the FAS but have changed my mind and may buy this one. Problem is it is left handed. Anyone got a right hand grip they want to sell ?

Thanks, Baz


http://i1225.photobucket.com/albums/...pscef55287.jpg

http://i1225.photobucket.com/albums/...psd7141547.jpg

[clarky]

Just put new seals in a FAS SSP for a local friend.Problem mainly was the tiny hidden O ring which seals the valve shaft, but I replaced all the seals as they cost me only 50p for all six. Tried to think of a way to hold the tiny aluminium valve so I could punch out the steel pin with no damage. I ground the shape of the valve in and old plastic screwdriver bit holder and put it in a vice. This stopped the round valve rolling around and I used a hollow tip starter punch to get the hard steel little pin moving, no problem. The hidden seal was quite badly worn, see pic. I have never been keen on the FAS but have changed my mind and may buy this one. Problem is it is left handed. Anyone got a right hand grip they want to sell ?

Thanks, Baz


http://i1225.photobucket.com/albums/...pscef55287.jpg

http://i1225.photobucket.com/albums/...psd7141547.jpg

Nice work ....Ive done a few in my time. Used a standard O ring selection kit from RS. Good for 10 repairs of all the seals but many preferring the better grade Nitrile rings for longer life.
Way I see it though, these regular neoprene rings have averaged 5 to 10,000 rounds in the 3 I have done and like you say pennies to replace once you have got the hang of servicing it.
You can also machine off some the excess of angle at the front of the Aluminium valve ahead of the O ring.
The actual head only seals on the O ring but the excessive angle beyond the seal restricts flow. Do not bother if you do not have access to a lathe as the increase is only small but an easy job for a skilled machinist provided the part does not go up in the air with an over enthusiastic cut. (there isn't much to hold but I used a pin chuck) I used small 0.1mm passes until bringing it down by a full 1.3mm and gained 15fps.

Only thing I cannot figure is why you didn't like it....whats not to like with a 604.

[micken]

Nice one guys, keep those FAS 604's going.

I've got a rear sight repair ongoing on one of mine.

Cheers,

Mick

[Benelli B76]

Clarky, you hit the nail on the head why I did not like the FAS when you recommended the mod. I have always found them to be underpowered when compared to my other SSP's, Baikal IZH46M and Airmatch 600.
Looks wise I like them. I have a lathe as I do gun work virtually every day, so I will nip the tapered end off the valve. Regarding the O rings I use Viton as the Shore hardness is up a bit on Nitrile at 74 degrees Shore A. Polyurethane would be better but expensive. As you say, you can get thousands of shots anyway. A chap on here has kindly offered to swap grips as he needs left handed, so has been a good day.

Thanks, Baz

[mrgeoff]

I bought a FAS that needed repair, was easy to replace all the O rings, I enjoyed it. Sold it to a friend cheap as im a lefty, should have kept it

[clarky]

Clarky, you hit the nail on the head why I did not like the FAS when you recommended the mod. I have always found them to be underpowered when compared to my other SSP's, Baikal IZH46M and Airmatch 600.
Looks wise I like them. I have a lathe as I do gun work virtually every day, so I will nip the tapered end off the valve. Regarding the O rings I use Viton as the Shore hardness is up a bit on Nitrile at 74 degrees Shore A. Polyurethane would be better but expensive. As you say, you can get thousands of shots anyway. A chap on here has kindly offered to swap grips as he needs left handed, so has been a good day.

Thanks, Baz

I might agree in regard of the power of the massive and agricultural 46m but the FAS handles so much nicer and looks so much better.
As regard the 600 I have found them equally powerful.
The FAS I have worked on have varied somewhat in power but set up correctly most of them will hit 400 fps with most pellets, similar or slightly edging a HW40. For this type of gun that's fine but with much greater finesse.
The 600 is a bit of an ugly bugger compared to the FAS.
The FAS is very slightly under compressed due to a .75mm clearance between the head and wall of the valve but this makes clearance makes it nice to cock.

[tacfoley]

Just put new seals in a FAS SSP for a local friend.Problem mainly was the tiny hidden O ring which seals the valve shaft, but I replaced all the seals as they cost me only 50p for all six. Tried to think of a way to hold the tiny aluminium valve so I could punch out the steel pin with no damage. I ground the shape of the valve in and old plastic screwdriver bit holder and put it in a vice. This stopped the round valve rolling around and I used a hollow tip starter punch to get the hard steel little pin moving, no problem. The hidden seal was quite badly worn, see pic. I have never been keen on the FAS but have changed my mind and may buy this one. Problem is it is left handed. Anyone got a right hand grip they want to sell ?

Thanks, Baz


http://i1225.photobucket.com/albums/...pscef55287.jpg

http://i1225.photobucket.com/albums/...psd7141547.jpg

I'm ambidextrous and used to teach disabled shooters, so I also had to buy a left-handed Morini grip when I found MY 604 back in 2000. Email me for pics of my RH grip - it might be what you are looking for, who knows?

tac

[Benelli B76]

I might agree in regard of the power of the massive and agricultural 46m but the FAS handles so much nicer and looks so much better.
As regard the 600 I have found them equally powerful.
The FAS I have worked on have varied somewhat in power but set up correctly most of them will hit 400 fps with most pellets, similar or slightly edging a HW40. For this type of gun that's fine but with much greater finesse.
The 600 is a bit of an ugly bugger compared to the FAS.
The FAS is very slightly under compressed due to a .75mm clearance between the head and wall of the valve but this makes clearance makes it nice to cock.

Beauty is in the eye of the beholder, so my opinion is different to yours, I quite like the lines of my 600 and its low profile in the hand. If FAS had made their pistol 22 mm longer, would have looked better and increased the velocity up to 450 fps so you don't have to fiddle with it.

Baz

[clarky]

Beauty is in the eye of the beholder, so my opinion is different to yours, I quite like the lines of my 600 and its low profile in the hand. If FAS had made their pistol 22 mm longer, would have looked better and increased the velocity up to 450 fps so you don't have to fiddle with it.

Baz

You are correct...beauty is in the eye of the beholder but you are possibly alone on this one. Virtually everyone seems to agree on one thing that the 604 is the most elegant of air pistols ever made, save for a few that support the LP53 over it. Both beautiful. The 600 also being Italian, appears to follow similar elegant lines but with the bulky sidelever arrangement spoiling it a little. Quite a big thing in the hand too.
The extra 22mm will not give you the 50 fps you suggest. Try 42 mm. I already did a Walther barrel extension to fit inside the sight extension (optional extra) on the FAS It gave approx. 20 fps.
Increases of over 2 inches (50mm) start to get to the 50 fps sort of area in guns like the HW40 but at this point, the look of the gun virtually ruined.

[Benelli B76]

What more can I say.....
Baz

[tacfoley]

I love my two mint and boxed LP53s as well - one black grip, and one brown.

tac

[Bobupndown]

It might interest you to know that The FAS 600 is being built again under the name FAS 6004
http://www.all4shooters.com/en/news/...essed-air-gun/

[Benelli B76]

Gingernut and I have been discussing the new 6004, not sure where the high cost comes from for this pistol. Suppose some people will shell out for it. Took mine to the range today for accuracy and chrono test. Got it putting out 390 fps with Geco which I suppose is par for the course, have not shortened valve top yet. Still nowhere near the FWB Model 2 I was shooting at 520 fps. People may ask why we need more velocity, it is because we shoot pistols at targets out to 30 metres at our range, rifles to 70 metres. Does anyone recognise the rifle I took today, has special long barrel fitted.

Baz

http://i1225.photobucket.com/albums/...psb7635523.jpg


http://i1225.photobucket.com/albums/...ps10f4e595.jpg

[clarky]

Gingernut and I have been discussing the new 6004, not sure where the high cost comes from for this pistol. Suppose some people will shell out for it. Took mine to the range today for accuracy and chrono test. Got it putting out 390 fps with Geco which I suppose is par for the course, have not shortened valve top yet. Still nowhere near the FWB Model 2 I was shooting at 520 fps. People may ask why we need more velocity, it is because we shoot pistols at targets out to 30 metres at our range, rifles to 70 metres. Does anyone recognise the rifle I took today, has special long barrel fitted.

Baz

http://i1225.photobucket.com/albums/...psb7635523.jpg


http://i1225.photobucket.com/albums/...ps10f4e595.jpg

Yes Geko work quite well in the 604 because the barrel is slightly choked at the muzzle, presumably to aid accuracy but means it prefers strict 4.50mm pellets for best velocity.
The valve head would give you 15 to 20fps more depending on how far you want to go with machining off the angle.
Incidentally, an un-choked length of Walther barrel (I got my length from Chambers) adds about 15fps to regular pellets like Hobby. I found this out when reducing down the extra long barrel version for a friend after he decided he didn't like the look of his 604 with the sight base extension but he did like the extra 15 fps he got from the Walther barrel at same length as design of the original.
He was doing 427 with Hobby last time we tested..

[Benelli B76]

Clarky did you find that any extra barrel length produced more velocity, or did it have a detrimental effect ? I know on most guns like CO2 and PCP it puts up velocity, but with the short explosive release of air in a SSP a long barrel could slow the pellet with friction on the last few inches.

Baz