Tuning Sorting FX Pellets

[superduty250]

Does anyone have any experience sorting FX brand .25 caliber 25.4 grain pellets. I have just been tuning my Avenge-X for these at 910fps and got pretty good results for a whole string of 100 shots. However, shot to shot deviation looked higher than I wanted. So, this morning I sorted a bunch and was surprised a how much deviation they had. They ranged from 25.00 up to 26.00 with most being 25.1 to 25.6. So, I used a group of 15 of the 25.3 + or - .05 group. This shot string had a spread of 6fps and STD of 1.51! The first 15 shots from a random unsorted batch from the same tin had a spread of 12fps and STD of 3.42. I had hoped sorting would help but I was not expecting this much improvement.

So, my question is this what others see with FX brand pellets. Are the JSB pellets more consistent?

Also, should I be using sorted pellets when trying to come up with a good tune?

 

[Airgun-hobbyist]

I've found that weight quality and consistency runs in cycles. New dies and equipment are what seems to be where it's at for thwse "cycles." Sometimes the JSB tins are more consistent and sometimes the FX are. If I get a batch from either brand that are out as much as your's are then I sort them into piles per tenths of a grain and shoot up each pile separately. If the pellets in the batch of tins all weigh within a few tenths of a grain I don't waist my time sorting because they usually shoot pretty consistent.

 

[nervoustrig]

For what it's worth, I looked back at a sampling of pellets from 3 tins of the heavies bought at different times, and they showed a weight spread of around 3% (highlighted in the screen cap below).

It so happens that all 3 tins grouped well at my usual practice range of 50 yards.

Note this is from a sampling of only 60 pellets but that's usually enough to find evidence of major outliers, which is usually what I'm more interested in.

Also, here's a graphical view of the weight variance:

(If you're wondering why you don't see any 3% or higher is because this is relative to the average)

 

[WorriedMan]

Steve, at AEAC, toured JSB in 2019, interesting video, especially "MythBusters" section towards end, YouTube should have. JSB makes FX pellets, procedure slightly different for FX. For example, deciding a production run of 25.4 grain pellets is needed, JSB sets up eight machines with 8 dies, all of which are varying in age and hours used. Of these 8 machines all pellets coming from a single, randomly selected machine will be designated as FX, everything else is JSB. Considerable range of weights/sizes are generated, JSB handles by blending pellets in each tin. FX pellets, coming from one machine/die, should have less range of weights/sizes. WM

 

[superduty250]

I guess the good news is that my Avenge-X tune is not so bad after all. If I write off some of the sharks teeth as inconsistent weight variation it would look a lot better. Here's the graphs of the full 115 shot string and then the first 100 where the tank pressure started dropping below the regulator setting.

UPS just now delivered my .22 caliber barrel kit and a bunch of JSB 18 grain and JSB redesign shallow 25.4 pellets. I'm going to clean and install the barrel and start some more fun. I think I should weigh a few of each to see how consistent they are.

 

[superduty250]

I just sorted the last 303 FX 25.4 grain 25 caliber pellets from my last tin. I'm attaching the chart FYI.

 

[manabeknives]

That's really sad

 

[beerthief]

Imagine what pellets would cost IF the companies met our demands ? $30 a tin ? $47.95 a single tin ? pellet count per tin ? 150? , 250 ?

EDIT : thinking i am way to cheap in my imagination .

 

[superduty250]

I just did a full tank string of 120 shots using the sorted FX 25.4 25 caliber pellets. The first 91 were all the 25.2 weight group and the rest were the 25.1 group. Wow, what a difference I am no longer disappointed with the consistency of this 910 fps tune! I've attached a chart of the whole string, the first 100 shots and the first 30 shots. looks like bottle pressure started going below the regulator setting around 100 shots. I shot it all the was down to about 105 bar bottle pressure. I am still only shooting to get the fps consistent for the tune. It's too cold and snowy right now to shoot outside. I am really curious to see how the low ep and std relate to accuracy. Steve AEAC said 910 fps was a good speed for these pellets in the 25cal Avenge-X so I am hopeful.