FAS re-seal

[clarky]

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

It does increase power but I have never pushed the length of the barrels of these type pistols to find at what point it cannot increase power any further, or begin reducing it as you rightly suggest,
The 3 mods I have done are all in keeping with the look of the guns rather than spoiling there appearance.
My HW75 had extra length of barrel to the true muzzle instead of stopping 28mm short as design.
This gave me approx. 22 fps.
The 40 has a shorter void/compensator design which adds almost 20mm of extra length for 17fps and the FAS 604 sight extension allows 34mm of increase. It was difficult for me to work out exactly what the increase was here as I had also had a small gain from having no choke built into the Walther barrel blank in Mikes mod.
I.E 34 mm barrel increase but also un-choked Walther barrel gaining about 15fps or so with some pellets for a total of almost 40 fps

As a note for mods before zorching this post......MAX increase never exceeded 3.4ftbs in any of the work under taken here!

[Rickenbacker]

Does anyone recognise the rifle I took today, has special long barrel fitted.

Baz



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

Most of it looks like a BSA Superstar?

ATB - Phil

[Benelli B76]

Phil, you got the family name right, BSA, but this rifle is a precharge pneumatic, the good old Firebird with a couple of bling parts. Also have its stumpy little brother the Spitfire.

Regards, Baz

[Rickenbacker]

Phil, you got the family name right, BSA, but this rifle is a precharge pneumatic, the good old Firebird with a couple of bling parts. Also have its stumpy little brother the Spitfire.

Regards, Baz

Ah yes. I'd forgotten about those BSA PCPs, and how similar they look to the springers... perhaps BSA could have gone for the 'full set' by making an SSP version!

[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

Just for additional info Baz (or anyone else interested) I have proved fairly conclusive that the FAS barrel crown IS beneficial, even versus that of Walther barrel blank I tested against.
I used a variety of ammo Monday evening over the club range rested at 10 Mtr with both barrels.
Mike asked me to trim the Walther barrel down to design spec, as he disliked the extension on but wanted to see if the Walther barrel gave any improvement over the Italian rifling instead of just wasting it.....it didn't, despite great care with the crowning.

Although the un-choked Walther barrel gave approx. 15 fps extra across all the pellets used, the FAS barrel cut group sizes by up to 3mm. The RWS R10 and excellent Geko (recommended) both better through the choked bore of the FAS.
We closely inspected the rifling but couldn't see the choke but after pushing the Geko through with a un-felted cleaning rod, clearly felt the slight restriction at the last 20mm and deeper cut rifling was present under a small magnifier when the pellets popped out.

Conclusion....stick with the FAS barrel but go for the valve mod...20fps available with that but be careful.

[micken]

Just for additional info Baz (or anyone else interested) I have proved fairly conclusive that the FAS barrel crown IS beneficial, even versus that of Walther barrel blank I tested against.
I used a variety of ammo Monday evening over the club range rested at 10 Mtr with both barrels.
Mike asked me to trim the Walther barrel down to design spec, as he disliked the extension on but wanted to see if the Walther barrel gave any improvement over the Italian rifling instead of just wasting it.....it didn't, despite great care with the crowning.

Although the un-choked Walther barrel gave approx. 15 fps extra across all the pellets used, the FAS barrel cut group sizes by up to 3mm. The RWS R10 and excellent Geko (recommended) both better through the choked bore of the FAS.
We closely inspected the rifling but couldn't see the choke but after pushing the Geko through with a un-felted cleaning rod, clearly felt the slight restriction at the last 20mm and deeper cut rifling was present under a small magnifier when the pellets popped out.

Conclusion....stick with the FAS barrel but go for the valve mod...20fps available with that but be careful.

Many thanks for this, good attention to detail in your testing and good to know that the original pistol benefits from similar detail in its design and build quality.

Cheers,

Mick