Power problem Brocock Grand prix
I bought a new .177 Super 6 Brocock Grand Prix pistol last month and have put around 250 pellets through it to date.
Today I decided to check the power with my chrono and was staggered to get a reading of around 1.8 to 1.9 Ft Lbs using Hobby pellets (7.0 grains). FPS was around 340-350.
I had filled the pistol to 190 BAR and everything is as it was when it left the shop.
Stranger still is that when I put some JSB Exact Heavys (10.4 grains) in it (heavy pellet for a pistol I know) the Ft Lbs on the chrono jumped to around 2.9-3.0!
I immediately suspected the chrono as having a fault, but when I shot Hobbys again, I got 1.9 and 340 FPS - just like the first time. I went to some Daystates at 7.9 grains and got 2.2 Ft Lbs.
It seems that the heavier the pellet the higher the power.
I realise that the Brocock is not regulated, but 1.8 to 3.0 is quite a 'swing'?
(I have since chrono'd my EV2 rifle and got 11.2 Ft Lbs, so the chrono seems to be working fine.)
SO, what's wrong with my Brocock? and why do I get such a big jump in power with the heavy pellets?
I appreciate that the 6Lb limit has to cater for any weight of pellet, but even with Exact Heavys 3.0 is a bit low?
Thanks
Robert
How long a minute is depends on what side of the bathroom door you're on.
Air Arms EV2 MK 3, BSA R10 MK 2, Crosman 357 Magnum revolver