choke question

[Bill Murphy]

Bore micrometer, the one that most of us use, Skeets brand, Brownell's catalog, about $95.

[William Davis]

That's the one

William

[6pt-Sika]

I've got one at the shop that looks like a set of calipers but with about six inch depth capabilities . Don't really care for it however but it's better then nothing . I do have a good friend that has a nicer one that's good for everything from 10 gauge to 410 and that thing from Brownells was like $700 !

[Ed Blake]

I'll second the Skeets gauge. I believe the Parker Story talks about the change in bore diameter happened in the early 1890s. Austin Hogan did research on this also. The 1879 lifter I had had bores of .750 with about 30/1000s choke in each barrel. I miss Austin. Every time he spoke I learned something new about Parkers.

[Dean Romig]

Originally Posted by Ed Blake

I miss Austin. Every time he spoke I learned something new about Parkers.

You can sure say that again!





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[Mike of the Mountain]

Originally Posted by Paul Ehlers

Just to add my two cents worth to this discussion.

All of the above posters are spot-on with their explanation of choking. Parker themselves relied heavily on the patterning board for the purposes of determining the choking of a particular set of barrels.

I have several PGCA letters on the various Parkers I have owned. In a majority of these letters Parker in their records recorded choking as percentage of a certain size of pellet patterning in a specific size of circle at a specified yardage. As an example "left barrel patterns 180 pellets of #7 shot in a 30" circle at 40yards distance"

In my small sampling of letters. I have found this to be the normal means the factory used to determine choking. I do have a few letters where the chokes are stated as Full & Full, IC-Mod etc. My conclusion based on the letters I have seen is that Parker spent a lot of time at the patterning board to get their chokes just right for any particular gun.

Bottom line is the only way to really determine how your gun is choked is to spend time at the patterning board.

Yup, Paul nailed it. Fox did the same thing. They patterned the guns for specific chokes. I see it would be the technologically correct way to get the actual choke/pattern combo instead of the modern industry standardization, but I wonder if there was more to it than that? Issue with components and reliability? Difference in individual barrel smiths and the way they made their product? Difference in machining? Anyone know?

[Double Lab]

Originally Posted by Mike Koneski

Issue with components and reliability? Difference in individual barrel smiths and the way they made their product? Difference in machining? Anyone know?

I don't know for sure Mike, but probably a combination of all of the above. Of all the things that fascinate me the most about Parkers and Foxes are their attention to their choking. A true shame to screw with them.
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[Mike of the Mountain]

I need to make an addendum to my post. Fox did pattern some guns when it was requested to be certain percentages or with a specific load, they didn't pattern every gun. That would be expensive!!

[Dean Romig]

I've seen a lot of Parker hang tags, including many Trojans, and I have never seen one that hasn't been patterned.




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[Double Lab]

Great point Dean (as usual) but today we would be unable to duplicate Parker's load. So getting back to John's OP, John, pattern your gun for point of impact, then try different loads as see which ones your gun likes. Don't worry about your chokes. You can get them tighter or more open by changing loads. Shoot a few hundred clays with it and you'll get a feel for her performance.