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Member Joined: 30 Nov 2011 Posts: 1696 Location: Minnesota

I've received 2 old partial bags of Remington DuPont chilled shot, but unsure of size. One bag is clearly marked from the factory as 8's, but has 6's handwritten on it. The other bag I can read the CH from the factory on, but the size is not readable but best guess is 5's. It seems like I've seen a chart showing the actual size in inches of the various shot sizes, but cant find one. Anyone know where I can find one? I'd like to try to figure them out with my dial caliper. Thanks

Member Joined: 30 Nov 2011 Posts: 1696 Location: Minnesota

Thanks for the quick reply Mike!

In the case of US spec birdshot, you don't really need a chart if you remember this: The diameter of number "zero" shot is .17" Zero shot is also the same as "B", incidentally. As the shot number gets larger, just subtract .01" for every number greater than zero from that starting point of .17" So #1 is .16", #2 is .15" etc,etc. Sizes larger than Zero, or "B" get more complicated, but the rule holds true upwards in increments of .01" for "BB", "BBB". I don't know the convention after that. Incidentally air rifle shot is .177" so it can pass down a bore of "BB" size -- .18" dia.

European shot sizes are slightly different, and different from one country to another at one time or another. The difference can be quite significant. Some Gamebore 65mm 16's I had were listed as #6, but were barely #7.

If you are measuring shot out of a bag to determine it's diameter, then best keep in mind that there is an acceptable +/- tolerance of about 0.005" for any pellet size. The total tolerance equals about one full pellet size. As an example, #6 shot can measure anywhere between 0.105" to 0.115" in diameter out of the same bag.

We will also usually find a few pellets a full size up or down in the same bag. This amount of variance tends to negatively affect the uniform ballistic performance of the shot swarms of finer shot sizes more than bigger ones, but the affect tends to also be mitigated by the higher pellet count if the shot charge weights are equal.

Joined: 26 Apr 2010 Posts: 3177 Location: NCWa

16gg-

I'm reminded of this whenever I clean-up the spilled shot. I'll caliper it and sort it by size. I've found particularly the small shot to have no specific size groupings, so anything smaller than .082" goes to size 9, .083-.087" is 8.5; . 088-.092" is size 8 and .093-.098" is 7 1/2. Sizes 6 and larger seem to be closer to the size index, but since I load a lot more shells for clay targets (so smaller shot) I spill a lot less of the larger ones, so have less experience in resizing them.

Recently I started loading with size 7.5 Nice shot. At $2/oz I find I spill significantly less of it than lead. Smile