Just to share with you my findings with the JSB Exact .177 heavies ( 10,34 gr ). In the field, its behavior is simple amazing ( as Hector said before ), both in accuracy and knock down, and mantaining the cinetic energy.

Cronographic Test of a Diana 45 T01 4,5 mm (177) with different pellets: 11/05 3 shots average Cinetic energy: ½ masa . v2

Gamo Match ( 7,5 gr )

Muzzle: 276 mts/s
35 mts: 178 mts/s
% of velocity reduction at 35 meters: 35,5 %
cinetic energy: 1188 J ( 53,4 % )

RWS Superpoint ( 8,2 gr )

Muzzle: 263 mts/s
35 mts: 185 mts/s
% of velocity reduction at 35 meters: 29,6 %
cinetic energy: 1403 J ( 63 % )

RWS Superdome ( 8,3 gr )
Muzzle: 265 mts/s
35 mts: 195 mts /s
% of velocity reduction at 35 meters: 25 %
cinetic energy: 1578 J ( 70,9 %)


JSB Exact ( 10,34 gr )

Muzzle: 239 mts/s
35 mts: 207,5 mts/s
% of velocity reduction at 35 meters: 13,2 %
cinetic energy: 2226 J ( 100 %)

Best wishes, Teotimo

I just picked up three tins myself. I've only tried them in my AATX200HC and they look good so far. I'll try them out again later this morning. I've got a Beeman R11, R9, and a RWS 34 to run them in yet.
Winters coming fast here so that screws things up here a bit. My shooting is done at 35 yards and at 52 yards.
I've also dropped 11 rabbits in the back yard as well, like to see how the extra 1.5 grains in weight do on them.

Lippold

Teotimo,

 Thanks for posting that info!

 I have been considering trying some heavy pellets in a couple guns to helptighten groups. Your readings look promising to support my plan!

 By the way, not only Magnums benifit from the use of heavy pellets!

 My VERY inexpensive,Plastic reciever, Crosman 760 "D" (Last rifled barrel Model of the 760) loves the "Heavies"!  The rifle was a $24 Wal Mart purchase. I shoot 11.5 gr Beeman Silver Stings and 10.5 grain Crosman Premiers through it. The rifle has a fixed 4X scope. Charging it at 6 to 8 pumps, shooting over a rest, the little Crosman will group right alongside my HW-55 out to 20 yards! This just goes to show that one needent snub their noses at those inexpensive Pneumatics...

 Thanks again for the information!

 ZVP

 

Dear Marcelo:

If your Crossman like the heavies, he will like the Exacts. I have to say that I did not have the opportunity to try the Crossman Premiers or Beeman pellets, but the Exacts are certainly superior pellets. Try them hunting and you´ll see !!

Best wishes, Teotimo

Dear Teotimo,

Not wanting to be pedantic but 1578 J is the muzzle energy of a .222 Remington.
Energy in Joule is calculated as follows:

m/s x m/s x gram
---------------------
2000



Joris

Dear Joris:

Your input is certainly wellcome. To be honest, I don´t know too much about physics, or serious ballistic. I wanted to know more than data from the muzzle velocity; specifically, what happend after the different pellets "travelled" 30 or 40 meters. That´s why I put my Chrony at 35 meters and discovered that there HUGE velocity differences between pellets of different brands, probably because their different ballistic coeficients, among other resons. The problem was that some pellets weight more than others, therefore I had to stablish a way to measure the power taking account of the their velocity and weight. That´s why I´ve applied the kinetic energy, which as far I know is:

Kinetic energy: 1/2 of the pellet mass x Veloc2

Your formula IS THE SAME THAN MINE, written in a different way. Try with 280 m/s and 16 gr with both, and you will arrive to the same result.

Probably my mistake was with the decimals, this means that instead of write 1578 J, should be 157,8 J.

Could you help me please to know if this is correct ??

Best wishes, Teótimo

Dear Teotimo,

Looking at yout formula again, you are right:

Kinetic energy: 1/2 of the pellet mass x Veloc2

but you should take the weight of the pellet in gram and not in grains and at the end divide by 1000
10,34 grains x 0.0648 = 0.67 gram
(0.67 : 2) x 239 x 239 = 19136 : 1000 = 19.14 joule
(0.67 : 2) x 207.5 x 207.5 = 14425 : 1000 = 14.4 joule

... by all means sufficient energy for rabbits

Keep well,


Joris

Dear Joris:

Thanks for help me to realize that the formula should be in grams !!. I´ll modifie all the obtained numbers. Anyway, these results using grains were useful to compare the different performance of the different pellets.

Best wishes, Teotimo