Inspection dates i believe are only for german law,not enforced here
I've just bought a Rohm Twinmaster Top for Pistol HFT and plinking.
After the initial 10 minutes playing around with it, and measuring the power over the chrono, I thought I'd try filling the cylinder.
Normally, I use the BestFittings QR fixings for my HW100, but the adaptor that comes with the pistol screws straight into the charging head, and as I had a spare 3l bottle, I thought I'd use that.
Problem was, as I screwed the Rohm cylinder onto the probe, it just dumped all it's air through the bleed hole on the back of the charging head.
On close inspection, the Rohm filling probe is too short for the depth of thread on the charging head, so the hex flats bottom out long before the seal contacts the seat.
Is this a safety feature (maybe to stop 232BAR devices being screwed into 300BAR bottles)?
Both of my 300BAR bottles have the same problem.
What can I do to overcome the problem?
I've looked on the BestFittings website, but their Rohm probe looks exactly the same as the one I have.
Suggestions welcome.
Also, how accurate is the "inspection date" printed on the air cylinder? The manual suggests that the inspection should be every 10 years, but the (new) spare I bought suggests the next inspection is due in 2011 (next year).
How can this be possible? Have these things been around for 9 years?
Thanks.
Bob.
Inspection dates i believe are only for german law,not enforced here
Best Fittings have an adaptor which allows your 200 Bar din to screw into a 300 bar din bottle - just take care you limit fill to 200 bar.
IanR
Daystate MK4 S .177 ~ Steyr LP2 ~ Brno Tau-7
Thanks Joker, I've just ordered the 1/8" BSP adaptor from BestFittings. Their 232DIN adaptor is exactly the same as the one that came with the Rohm, but I can use the 1/8" adaptor with their QR fittings.
Thanks.
Bob.
try using a douty washer (a washer with a rubber seal built in) at under 20p its worth a go
as for power use the single shot mag as it can be adjusted to give a extra 1/2 foot pound and makes it a bit more accuratebut 3 foot pound is it's max (un-modified) limit
it's accuracy is fantastic but trigger (which cannot be adjusted) will let let you down in 10m mach computations (it did me)but get used to the gun and find a pellet it likes you've got a winner
Last edited by airgunnut; 22-05-2010 at 02:43 PM.
I've noticed that the single pellet tray and the magazine both give exactly the same power (2.6 ft/lb), but if you cock the trigger first, it goes up to 3 ft/lb with both the mag and single pellet tray. On mine, there really is no difference.
Cocking the trigger gives a good one-stage match trigger pull, but the "normal" double action trigger pull is somewhere around 8 lb!!! Not much good for target comps, but quite good fun.
Bob.
the single pellet tray can be adjusted thanks to the little grub screw on it, it closes the gap between the tray and the barrel to give slightly more power
Airgun Repairs, Bespoke Airgun Smithing and Precision Engineering Services
http://www.magic9designltd.com
Is there a proper tool to do that? It looks like it would be very easy to slip whilst undoing the nut.
Thanks.
Bob.
Bob,
Once I can walk & stand for a while again I'm making a tool for the castellated nut, if I can get it done for the Gala I'll bring it along.
I'll bring my genny, dremel etc. and do your Rohm tune for you on the day if you like, or supervise you doing it if you prefer.
The job is fully reversible by removing the fitted components leaving the Rohm in standard trim once again,
Regards,
Nick
Airgun Repairs, Bespoke Airgun Smithing and Precision Engineering Services
http://www.magic9designltd.com