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Forums Pellets, Projectiles, & Ammo Notice anything?

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    Tominco
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    All of these are 25grain .25 caliber JSB’s…
    (never mind the little dents, that’s from me practicing)

    So, what’s the story? 
    Well, I recently picked up a tin from AoA and a tin from Pyramid Air in order to find out. The tin from AoA is a 6.35 head size specific tin (per the small sticker on the bottom). The ones from AoA have the shallow skirts. The ones from Pyramid Air have the deep skirts. These are the non-specific head size with a large white sticker on the back. The decals on the top of the tins are exactly the same. So, there’s no way to tell what you’ve got unless you check the bottom or know what your source is sending you. 
    ​I happened to notice this during competition. I’m pretty sure this contributed in some small way to a lower place finish for me. Needless to say, I was pretty angry about it while on the firing line. Even that can cost a shooter points. This has been my driving force to sort my pellets. 
    I will be doing further sorting and try to extract more details about the differences over the course of this Summer.

    So, let this be a caution to you…
    If you order your pellets from multiple sources, you might want to keep them separated or mark them in some way! 

    Happy Shooting! :)
    Tom

    • This topic was modified 1 month ago by Tominco.
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    Willie14228
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    Did they all actually weigh out at 25 you would think that different skirt depth would change the weight.

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    T3PRanch
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    I noticed this “change” a few weeks ago. My thin skirt batch is a year old from PA while the thick skirt batch is only a couple of months old from AOA!

    It might be that JSB has “fixed” the “thin skirt problem” with the 25.4’s. The thicker skirt seems much less prone to denting.

    Thurmond

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    Regal_US
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    Incredibly annoying. There has to be a weight difference between the deep and shallow pellets. It would be great to confirm that. I like how you loaded alternating deep & shallow!
    The difference reminds me of JSB 16 and 18 grain in 0.22, though hopefully if there is a reproducible difference, its smaller for the 25 grain pellets.

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    I knew that would be the first question… lol :)
    5 random pellets from each tin
    Pyramid (deep)…
    25.42
    25.46
    25.56
    25.54
    25.44

    AoA (shallow)…
    25.52
    25.22
    25.24
    25.38
    25.62
    I wouldn’t call this conclusive by any means. After all “Life is like a box of chocolates. You never know what your gonna get.”

    It doesn’t surprise me that the weight are not consistently higher/lower. If you look at the picture carefully, you’ll notice that the deep ones look conical. Similar to a funnel. The shallow ones are more like a bucket with straight sides. So, they made the change without affecting the weight. 

    Here’s a pic of the ten that were measured. I don’t see any significant difference in the shape of the pellet.

     

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    Maybe the outside edge of the head has a bit more surface area on the right 5.

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    Regal_US
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    OK, if weights have similar spread, what causes difference? Is it BC?
    If you shoot the deep and shallow separately do they both group well, but with different impact points?
    Which did you decide to stick with, and why?

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    Regal, 
    I haven’t done any in depth testing yet. That will come later on this summer. 
    However, I can tell you that I stocked up on the AoA ones. My reasoning is, that sticker on the back that says lot ######## size 6.35. The fact that ALL of my pellets are of the same lot# gets me that much closer to consistency. I took a chance that the lot was a good one and bought a whole brick. Time will tell. Winters are so long out here that I’m only just now getting to test pellets I bought 6 months ago. In fact, it looks like a pretty good size snow storm will hit me at work over the next 2 days. ugh. 
    Tom

     

    • This reply was modified 1 month ago by Tominco.
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    The right 5 look taller and the shape of the dome looks different 

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    Mrv
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    JSB Label Numbers Explained

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    Willie14228
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    “Tominco”Regal, 
    I haven’t done any in depth testing yet. That will come later on this summer. 
    However, I can tell you that I stocked up on the AoA ones. My reasoning is, that sticker on the back that says lot ######## size 6.35. The fact that ALL of my pellets are of the same lot# gets me that much closer to consistency. I took a chance that the lot was a good one and bought a whole brick. Time will tell. Winters are so long out here that I’m only just now getting to test pellets I bought 6 months ago. In fact, it looks like a pretty good size snow storm will hit me at work over the next 2 days. ugh. 
    Tom

    (Thanks Mod2, I’m back up and running again!) 


    Jumping Jehoshaphat
    SNOW STORM!!! Where do you live Tom? The North Pole!! LOL

    You know I’ve always wondered about the Skirts and the effect depth and shape could have on the speed and chamber pressure.

    I mean let’s upsize this a bit and consider it’s effect.
    My very small extent of hot rodding experience included using different valves and pistons to increase (Or decrease) the compression.

    If you think about it when the pellet is loaded in the chamber the space behind the pellet would be the amount or volume of space available for what ever pressure you have your gun set to…. right?
    So this would mean that if you are shooting with a moderated valve would it shoot with the same amount of pressure and therefore more or less volume depending on the depth inside of the skirt?
    Or would the volume stay the same and therefore be a change in pressure  (chamber pressure) 

    If both choice of pellets weigh out the same then I would assume that the mixture of the lead is different and therefore the hardness also would be different  
    This would or could effect how the pellet ingages the rifling 

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    Willie,
    Tom-in-co. Colorado :)

    I’ll say the same thing as you but reference it over a larger scale. This is why I’m on my own quest to find “perfect pellets”.

    ANY variation will affect the overall consistency of your rifles shooting. When you think about all the variables that can affect the rifles ability to deliver exactly the same shot 2 times in a row, you quickly realize that it is next to impossible to achieve. 
    But, we do what we can to limit those variances as much as possible. From polishing barrels, to adding regulators, to adjusting speeds, weighing, sorting… the list goes on and on. Removing this small variation is one step in that process. And your right, the trickle effect from this one small thing leads us to other factors like you mentioned. Hardness of the skirt. Flexibility of the skirt. Engagement of the rifling. Balance in flight. Just to name a few. 
    I think a vast majority of our shooting does not require this much attention to detail. However, if you’re going for the gold against “powerhouse” shooters, every small variation adds up to lower scores. This is where these details really need to be addressed. 

    Then, there’s this thought…”WTF, JSB?!?” Your machinery can be tuned to turn out a much more consistent product from machine to machine. We turn to you for the highest quality pellets available. 

    Tom

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    Dartagnan
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    Pellets in the 22 caliber arena, pellets ordered from PA and AD, primarily, and shooting several thousands of pellets from 177 to 30 (22 & 25 cal most noticeably) it’s not a surprise different dies are used at the factory.  These 2 tins were purchased from PA but at different time frames.  Tin / pellet (LEFT) on the left was purchased in January 2017.  Tin / pellet (RIGHT) was purchased Sept 2016. Fortunately, I haven’t noticed any obvious difference in each of their performance since I’m not into competition.  However, on the side of pest control / target plinking, I still do like to have consistency. 

    Has anyone else wonder why Ted bought a boat load of pellets?  :)

     

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