Thanks, Lloyd. I bought one of these, but for much less money (I think it was around $40) to measure the .410s. It will reach in far enough to get past the choke so you can get a pretty accurate measurement of the constriction.

https://www.amazon.com/Internal-Dial-Caliper-1-375-Range/dp/B001CTJOJ6

I agree with that , KY Jon, and it seems to be tight enough for me on doves and quail if I watch my range closely, like you said your Dad used to do. My Yildiz .410 S X S is tighter, at .011" and .015". I have a Verona that I use for tournament sub gauge events that is choked .004" btm and .011" top. That works good for these events because there is invariably a bird that can be taken inside of 15 yards on nearly every station.

SRH

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