Pellet sizes

[panman3]

Hi Guys,
I am wondering if anyone has ever measured pellet head sizes? On my tin of JSB Exacts it says '4.52' so I thought I would check. I have recently bought a new micrometer and a digital vernier gauge and according to both the average head size is 4.46mm! I have tried measuring AA fields and H&N FTT with the same result.
I would like to measure skirt sizes but it's very difficult without squeezing them out of shape (especially the AA's - they are SO soft!) but they seem to be about 6.62mm

Any idea what is going on?

Cheers
Great site - keep it up!

[Blackbaronfish]

The sizes quoted on the tin are from the dies that make them.

BBF

[kevingambrell]

Yes I have more measuring equipment than you can shake as stick at, but measuring pellets is hard work due to how soft they are.
My best attempt was with a Mitutoyo digital DTI gauge on a stand and to be honest even the gentle pressure from the DTI plunger
slightly deformed the head of the pellet.
What it did do was show how inconsistant thay are if I assumed the same deformation on each pellet tested. None of the so called 4.52's
were the size stated all varied few a few hundreths of a MM.

[raygun]

I have no comment.

ATB
Ray.

[panman3]

Thanks Blackbaronfish but I thought the die used was the first digit-going from 1 up to (I think) 5? That's what the guy at BAR told me(I think I understood him!)

[raygun]

Thanks Blackbaronfish but I thought the die used was the first digit-going from 1 up to (I think) 5? That's what the guy at BAR told me(I think I understood him!)

What Ray is saying is that the size quoted on the tin is actually the dimension of the die, not the die number.
You will not find that the claimed pellet size will actually match the true size. Normally they are around 4.47/8. That is the head size. The tail size will be bigger. As the die wears it will produce larger head sizes. You will get large variations in performance not only between head sizes but also between dies.
There is absolutely no consistency.

If you find a die that works well then buy as many tins as you can afford. When that die next appears it may not perform anything like.
It's also impossible for them to produce pellets that are just .01mm different in size.

ATB
Ray.

[panman3]

Thanks Kevingambrell and I agree there is a variation in head sizes but you say 'a few hundredths of a mm'. Correct me if I am wrong(maths was never my strong point!)but the 1st digit after the decimal point is tenths and 2nd digit after the decimal point is hundredths. So, the difference between 4.46 and 4.52 is six hundredths of a mm - am I right? I'm wondering if that is enough to make a difference? Duh! my head hurts now

[raygun]

They are claiming pellet sizes separated by .01mm.
That is one, two and a half thousands of an inch. It also has to be much less than this as a tolerance is needed to separate the nominal sizes.

You would need a temperature controlled gauge room before you could attempt to measure such close limits.
All this with a soft lead pellet that will not even be round. When you've done all this very close tolerance work you then throw 500 in a tin

Remember when we shot .177 and .22 pellets

ATB
Ray

[air gun]

They are claiming pellet sizes separated by .01mm.
That is one, two and a half thousands of an inch. It also has to be much less than this as a tolerance is needed to separate the nominal sizes.

You would need a temperature controlled gauge room before you could attempt to measure such close limits.
All this with a soft lead pellet that will not even be round. When you've done all this very close tolerance work you then throw 500 in a tin

Remember when we shot .177 and .22 pellets

ATB
Ray

I do

[Raj]

Remember when we shot .177 and .22 pellets

And which one was the best, Ray