Using the UK hammerspring - chrony numbers...

Using the UK hammerspring - chrony numbers...

Joined: October 23rd, 2005, 6:49 am

July 30th, 2008, 9:31 pm #1


Today I mounted a UK hammerspring and starting at a superlow 100 Bars (1400 Psi) I got 30 good shots down to 50 Bar (700 Psi). Pellet used was the 8.65 gn HN FTT.

763.00
765.00
762.00
762.00
763.00
761.00
768.00
778.00
776.00
777.00
771.00
773.00
770.00
775.00
777.00
776.00
770.00
773.00
776.00
777.00
780.00
774.00
783.00
778.00
775.00
776.00
769.00
777.00
770.00
772.00

Ave was 772 fps (235 mps) equal to 11.44 ft/lbs (15.50 joule) with a spread of 22 fps (6.70 mps) or 2.85 %.

The rifle is now much more quiet, the triggerunit breaks better with less effort and the SVP is lower then ever.

Not much work handpumping a Disco to just 100 Bars for 30 nice and quiet shots.

Downsides..?

Well, maximal usable range..

I will have good accuracy to about 44 yards (40 meters), as fullpower I had the same accuracy to 55 yards (50 meters).

I reckon its a small loss for a more quiet report and smoother shooting with less work pumping.


BSA Airguns Ultra .22 - Leupold EFR 3-9x33 VX-II
Benjamin Discovery 177 - Leupold EFR 3-9x33 VX-I
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Joined: May 16th, 2007, 11:05 pm

July 31st, 2008, 2:25 am #2

Looks really great.
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Joined: October 23rd, 2005, 6:49 am

July 31st, 2008, 9:41 am #3


Large circle is 25 mm and small circle is 7 mm.



BSA Airguns Ultra .22 - Leupold EFR 3-9x33 VX-II
Benjamin Discovery 177 - Leupold EFR 3-9x33 VX-I
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Joined: May 16th, 2007, 11:05 pm

July 31st, 2008, 2:48 pm #4

I did another barrel cleaning last night but it is raining out here today in the mountains.
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