I got me a digital caliper

[wingbatwu]

So, the first thing I decided to measure were my paintball barrels and iFit bore kit...

The Tiberius Lapco 686 checks out:
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The cocker Lapco BigShot 690 too
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The Dye DAM stock 688 barrel, not so much
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When I measured the TechT iFit kit, things got even weirder. (I am still missing the 688 sizer, due to a shipping error which is currently being corrected)
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The only TechT right-sized one:
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[skullcandy1993]

unfortunately most barrel inserts have deviations like that. When I had freak inserts it was the same way.

[chicago]

Just wanted to let you know that I know of two companies that hold the measure. I have a digital caliper too.

FLASC bore kits hold true (they are smooth bore).
Hammerhead seem to hold true, have gotten three fins so far, and each held up to the test.
The shells that CCm sells were also good; but, you'd need a CCM SR1 to use it!

[wingbatwu]

At least they're different sizes. Which is what ultimately matters IMHO, since you have to put paint through them to measure the bore sizer you need.

As for the Dye UL though, I am thinking they put the wrong barrel in the box, eg the 685 instead of the 688.