JSB Exact Heavy .177

[DJP]

Well the first surprise with these is their shape. Despite the familiar diablo illustration on the tin, these are actually a similar shape to Logun Penetrators - with a short head, long parallel-sided waist and short flared tail.

Air Ammo list them as 10.3grn, although I weighed 100 on a lab scale and came out with an average of 10.15grn - close enough, I guess.

The pellets themselves are bright and shiny, with no damaged ones in the tin. They also have an unusual smell, and possibly have some sort of lubricant on them. The label on the tin states 4.52mm.

To be honest, I only really bought these for power testing (well, realistically it's these or BisMags/Barracudas) but I figured I might as well give them a proper test while I'm at it.

Through my Air Arms 410 they group very well - the same at 25yds as the normal 8.4grn Exact. Over the chrono they gave 710 fps - which, using Air Ammo's weight, equates to 11.5 fpe. By comparison, the normal 8.4grn Exact gave 775fps for 11.2 ft lbs.

All in, they're a nicely made and accurate pellet. They may have advantages in FAC rated rifles or in terms of energy retention for hunting, but I'll be sticking to the original as at 12 fpe I can't see that they offer any real advantage for me.

[sniper-wolf]

I have tried these in FAC Air rifles and they are superb.
Give em a go.

[Maverick]

My 2 Theo's below love them and they are running under 12flbs :D I find these are less effected by the wind in comparison with its lighter brother.

[GATMAN]

I have used these in my S410 (sub 12 ft/lb) and the grouping was stunning:)

Paul.

[Murphy]

I shoot Exacts in my Mk3 and it loves them.
But it hated these for some reason which was a shame. :(

[bjarup]

I have used these in my Steyr LG110 HP (24joule)
They group better than the Barracudas, but I have difficulty finding the optimal velocity fps for these pellets with respect to accuracy.

I also find, that they are a very tight fit in the barrel. They go about 30ms slower than the Barracudas.

Any experience in this respect?

[NeilM]

I am about to start doing some longer range testing. But using them in a Pro-T set to 875 fps they are working very well out to 35 yards and just have an edge over Barracudas, but not by much.

Pellet on pellet at 35 is possible, and certainly regular 6mm groups are common.

Next tests will be at 50 to 55 yards, and then I will start to vary velocity up and down by 10 fps.

[minibbb]

what headsize works best in a .177 S410?

[bjarup]

I tried to size some JSB .177 4.52 Heavy to 4.51 for my LG110 as I thought that they where a little too tight a fit in the barrel (velocity dropped 50ms compared to the Barracudas)..

But the Steyr dosent seem to like the smaller size as groups open considerably when using the down sized pellets.

[DJP]

Well, I may have to change my mind and start using these as my stock pellet! They are definitely far more wind resistant than the 8.4 grn: The other day I was shooting some groups in the wind and the Heavys were still producing excellent accuracy in conditions where the 8.4s were all over the place.

[Rapidnick]

Well, I may have to change my mind and start using these as my stock pellet! They are definitely far more wind resistant than the 8.4 grn: The other day I was shooting some groups in the wind and the Heavys were still producing excellent accuracy in conditions where the 8.4s were all over the place.

Dave this is inevitable. The relationship between weight and wind resistance is absolute.The difference in profile of the different pellet shapes has an influence but it is slight compared with that of weight.
How is the babe by the way?:D

[Maverick]

My 2 Theo's below love them and they are running under 12flbs :D I find these are less effected by the wind in comparison with its lighter brother.


Well, I may have to change my mind and start using these as my stock pellet! They are definitely far more wind resistant than the 8.4 grn: The other day I was shooting some groups in the wind and the Heavys were still producing excellent accuracy in conditions where the 8.4s were all over the place.

Well I did try and give everyone a hint :p :D

[sniper22]

my airwolf is spot on with these in 4.52 flavour.