Barrel Wall Thickness
 

In perusing descriptions of Parkers for sale on the web, I've noticed that a few dealers list barrel wall thickness while most do not. Is it risky to buy one without this data? Is there any "rule of thumb" for minimum thickness, like for 12 or 20 ga barrels? Thanks for any advice!

Paul
I feel it is absolutely necessary to have a barrel wall thickness before you buy any Parker. On a 12 ga I use .025 as a minimum. Many a pitted barrel has been honed and that will let you to look for what else has been done to the gun
David

For what type of steel is the min .025 is this for damacus and fluid both as well as stub and twist I am wondering.

Dam and fluid

the same for 20 ga
 

Would it be different for a 20 ga? I should have said before, that's my primary interest. Thanks

Paul,

There is greater pressure as the gauges go from 12 to 16 to 20 etc. I would want a little more than .025 but could be mistaken.

Harry

I think I'd want to know who's doin' the measurin' and how... its a bit of a tricky business.

The Field March 7, 1891 Vol 77:325
http://books.google.com/books?id=inQ...=0#PPA9-IA6,M1

http://pic20.picturetrail.com:80/VOL.../365573248.jpg

UK Working Standards recomended minimum wall thickness measured 18" from the barrel breech from Double Gun Classics p. 56, Vol. 1, No. 4 Jan-Feb, 2006:
2 1/2" 12g- .028
2 3/4" 12g- .032
Re-proof recomended minimum- .024

The Hunter's Encyclopedia from the German proof house: minimal wall thickness at end of chamber, regardless of length, for 12, 16 & 20 gauge guns should be 2.3mm (.0906") for 'ordinary good steel' or 2.1mm (.0827") if a 'Special Steel' was used. For the 24 & 28 gauges, due to their higher pressures, 2.4mm (.0945") was recommended.
Minimal wall of .6mm (.0236") was recomended in the "forward third" of the barrel.

So if you start with typical Parker wall thickness of say .032 for all gauges ( heavy waterfowl guns were thicker) and honing once often takes .008, then you have .024, and then a second hone to clean the bores because used gun buyers like shiny bores because it shows the gun was not used much, another .008, and you are at......


I'm aware of a 20ga Parker ruptured barrel in the forward 1/3rd, wall thickness .006, but those bores sure were shiny. No obstruction.

Bruce Is not .006 below the mwt. of .025 that some say is ok ?