JSB .22 18.13 v 15.89 Pellets

[wymberley]

My immediate problem is that whereas I have plenty of the latter pellets and a sample quantity of the former, I have no rifle - more on that later. Velocity and energy is of no real consequence between the two when considering the quarry and max' range, but it would be good if anyone could give me an idea of which has the advantage at, say, 75 yards with an ME of 25 ftlbs regarding bullet path and wind drift.

MTIA

[villaman]

I am finding 15.9 hades are better at that speed  . I need about 950 fps to shoot 18 gr in my crown 

[scarecrow243]

use chairgun if you have a chrono

[wymberley]

2 minutes ago, villaman said:

I am finding 15.9 hades are better at that speed  . I need about 950 fps to shoot 18 gr in my crown 

Many thanks - forewarned is forearmed.

1 minute ago, scarecrow243 said:

use chairgun if you have a chrono

Use Sierra Infinity Suite.

[scarecrow243]

chairgun is an app on your phone so you can use it in the field plus its free not like  computer  sierra infinity suite £76 

[wymberley]

1 hour ago, scarecrow243 said:

chairgun is an app on your phone so you can use it in the field plus its free not like  computer  sierra infinity suite £76 

You're talking to a bloke who's only just discovered what an 'App' is. These thingy phones, are they free like the app or would I have to buy one? I've surprised myself that I actually have a computer and I use the Infinity (by the sound of it, it's lucky I 'acquired' mine) as I also shoot rimfire and load centrefire and full bore. 

[Ultrastu]

The difference between 16 and 18 grns is largely irrelevant  chose the one that groups best .

Next question .

[scarecrow243]

1 hour ago, wymberley said:

You're talking to a bloke who's only just discovered what an 'App' is. These thingy phones, are they free like the app or would I have to buy one? I've surprised myself that I actually have a computer and I use the Infinity (by the sound of it, it's lucky I 'acquired' mine) as I also shoot rimfire and load centrefire and full bore. 

Hi i use an older android phone and chairgun works no problem with it  i have a .22lr & .243 but i don't reload for the .243 i only use chairgun and an fx chrono for my .22  12f1lbs  & .25 f.a.c. air rifles

[wymberley]

On 08/07/2023 at 15:14, Ultrastu said:

The difference between 16 and 18 grns is largely irrelevant  chose the one that groups best .

Next question .

Many thanks, sorry for the delay - too much going on.

Picked up the BSA yesterday and managed to test the two pellets for velocity/power this morning. It's finally starting to look as if the 7 month delay has been worth it. The Huma regulator, the 16+" barrel and someone who knows what they're doing finally paid off.

The 18gn came home in 26.6 ftlbs at 813 ft/sec and the 16 in 25.6 at 852 . Between the two the average SD was just under 5 so there's a chance for some fair groups.

The only difference of any consequence is that the 18 has a slight edge with wind drift.

[Ultrastu]

So yes .if they are equally accurate  they should both realise there bc potential  .the 18 grn should therefore have a slightly higher bc over the 16 grn .around 

16 grn 0.032

18 grn 0.034 

The higher the bc the less affected a projectile  will be by the wind .

Thing is this difference is very  slight and any advantage can easily be masked by other factors .

Trajectory is similar. The higher bc will translate to less speed loss but from a lower muzzle speed (compared  to the 16 ) out to the  usual 50 yds or so and the pellet drop  difference is very slight .

Retained energy .- same  very small differences  not worth getting hung up on . 

Really the best advice is choose the most accurate or the cheapest or the easiest to find .

It's not until your talking about pellets with 4 or more grains of diffence that there can be clear advantages and disadvantages  . And then your better choosing a pellet thats in the middle as it will often give the best middle ground of all aspects .

Think .177 8 4 grns (ive not found a pellet that beats this in all my years of testing ) 

And for me I like the 13 .4 grn jsb in .22 as they fly fast and hold well .

 

Edited July 12, 2023 by Ultrastu

[Mice!]

7 hours ago, wymberley said:

The 18gn came home in 26.6 ftlbs at 813 ft/sec and the 16 in 25.6 at 852 . Between the two the average SD was just under 5 so there's a chance for some fair groups.

Like Stu says, there so close to not matter, might be interesting to shoot something lighter and heavier to see how they go.

[wymberley]

12 hours ago, Mice! said:

Like Stu says, there so close to not matter, might be interesting to shoot something lighter and heavier to see how they go.

That is the plan. In addition to the two mentioned, I already have samples of and the spec's other than the velocities on the Infinity for the 14.35 and 13.43. The lay of my land is such that I can always use it to offset the wind drift somewhat. Consequently, this aspect has become my shooting weak spot and is the reason why I started off at the heavy end - not having shot a puff gun for 65 years doesn't help and I really don't think that my ability will improve - more likely the oppossite.

[Mice!]

I personally wouldn't go lighter than the 14.3s the pellets I've seen that are lighter tend to have very thin skirts and suffer damage too easily. 

[Ultrastu]

I really like the jsb 13.4 grn pellets. 

They certainly  seem to go well in bsa .22 barrels at any speed you fancy up to 900 fps .probably  more .

The bc is around 0.027  which is pretty good for such a light and fast .22 

And the big advantage  is they certainly  don't penetrate  as much as the heavier pellets or travel as far down range .