JSB .22 25.39 shallow base issues?

MACTEN

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Nov 18, 2020
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I've been thinking about getting some of these to test in the Taipan and maybe a few others and like the idea of the pellet being pushed farther into the breech but...Are there issues with consistency with mfg now? I've been buying the FX JSB's for a few years mostly and don't really have issues except the skirts seems to deform from the mags into the breech on several air rifles and is likely the cause of some fps drops when doing chrono work. I'm also reading that the new shallow isn't really a shallow but a medium skirt.. Can someone educate me?
 
I can try to point out the differences between the FX/JSB MRD's and the JSB Shallows
IMG_0166.jpeg

The one on the left is the FX/JSB MRD and on the right is the JSB Shallow
the depth of the FX/JSB MRD is .1140 and the depth of the JSB Shallows is .0710
The Shallow has more surface area compared to the FX
Tthe skirt gets slightly thicker towards the bottom on the FX, the Shallow's skirt appear to be the same thickness to the bottom
Hope this helps
Mike
 
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