Not .22 but after measuring .177 JSB Exact and H&N FTT pellet heads............

January 5 2018 at 12:29 PM

nced  (Login SpringerEd)
YF12


Response to List of pellet head/skirt dimensions?

I wonder why they sold different head sizes. Some pellets from the tins marked 4.50mm were larger than pellets marked 4.52mm and visa-versa.
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I really can't image why .22 pellets would be different but the larger diameter may make pellet fit in the leade less critical.

The H&N FTTs weren't any better with a max head size variation of .005 INCH.......
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I found that while the Crosman Premiers from the 1250 count box had large heads, they were much more consistent in head size averaging 4.53mm to 4.55mm........
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Because of this I made up a pellet sizer that would reduce the pellet head to about 4.50mm for use with my tight leade HW95 and found that the resized CPLs also worked fine with my looser leade R9.........
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Actually, I made up a couple different dies, (4.48mm heads which works really well for the tight leade HW95 and 4.50mm die for the R9).....
Since then I bought a new .177 HW95 barrel and when inspecting the bore I noticed that it also had a tighter leade than the R9 so I replaced the "larger leade" R9 barrel with the new HW95 barrel so I only have one size of pellet heads to keep track of.

I tghink that as long as the pellet head and skirt are large enough to be "swaged a bit" when pushing into the leade, a couple 1/100ths of a mm doesn't make much difference. The issue is when a pellet is loose fitting in the leade that pellet head size becomes an issue. Even with the Exact tins labelled 4.52mm, most were smaller than listed and fit very loosely in the "large-ish" R9 leade. Matter of fact, when shooting a field target match I had two "dry fires" and would have had a third if I didn't see the loose pellet flip out of the leade when relatching the barrel.

Unless you want to do a lot of tedious pellet sorting, IMHO, simply find an accurate pellet that fits the leade consistently and ignore the "sizes on the label". I do have to mention however that the tin of 4.52mm labeled Air Arms domes I measured was much more consistent than the JSB Exact and there were a lot of 4.52mm AA domes that actually measured 4.52mm unlike the Exacts that most 4.52mm pellets were smaller.

Anywhoo.....my home sized CPLs shoot pretty good for me........
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Same gun, different head size....
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They even worked well for a HW98 after I did some work on it........
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This message has been edited by SpringerEd on Jan 5, 2018 12:32 PM


 
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