Is this to thin to be safe?

[Double Lab]

Originally Posted by Clark McCombe

Looks like I'll be calling Hosford.
But really isn't it the practice of checking the barrel after each shot for debris that determines the possibility of an accident?
Another question, how many times would a gun have to be shot for there to be wear on the barrel wall?

Checking the barrel for debris only prevents an obstruction leading to a burst barrel. The "wear" on a shotgun barrel referred to is due to not wear but by removing metal by reaming. I've always measured the bore and chamber diameters and if they are within specs for the gauge then that's good enough for my purposes.

[B. Dudley]

Shooting a gun does not wear down the wall. The walls get thinned out either by honing, backboring, exterior refinishing or… they were just made that way.

An obstruction will blow out a thin walled barrel and also a heavy walled barrel.

You need to get measurements at other more critical locations on the barrel set to make a completely informed decision.

[Cold Spring]

Here's a pic that follows on my post of yesterday. C-Grade Fox 12 ga with Krupp steel barrels, honed oversize by a hacker despite agreeing to a lesser overbore. Before the work he claimed to have a precision Sunnen hone but miking after the work showed an irregular succession of thin spots here and there. Wall thickness on this tube was .018" at the leade of its choke, and less that 50 shots with lighter factory ammo caused the bulge with its heavy choking. The other barrel was .020" thickness at the choke leade and it also bulged. As I'd posted .... lesson learned on thin barrel walls along with heavy choking; and who to trust for barrel mods. After this episode all my necessary bore honing has been done by Briley. Always uniformly dead nuts on sizing as requested.
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[Clark McCombe]

So, plan is to get a Hosford gauge, measure barrels, especially those where the chambers are 2 3/4, and not have any more work done to them.
Shooting them will not wear them out.
Use only light loads, even in repro Parkers.
As I am learning, heavier really doesn’t mean any better to break a clay.

[Double Lab]

Originally Posted by Clark McCombe

So, plan is to get a Hosford gauge, measure barrels, especially those where the chambers are 2 3/4, and not have any more work done to them.
Shooting them will not wear them out.
Use only light loads, even in repro Parkers.
As I am learning, heavier really doesn’t mean any better to break a clay.

Now you got it. Especially the not needing heavy loads to break a target and beat your shoulder.

[Craig Larter]

I believe Jon Hosford recommends .090 minimum in front of the chambers on 20 and 16 ga guns.

[Dean Romig]

I should post a picture of Oscar Gaddy’s assessment of my Damascus 16 gauge barrels back in about 2005 or so. I have it at home but I’m not there right now.
And he signed his name to it.




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[Steve Hodges]

Dean, please post when you have a chance

[Drew Hause]

Here ya' go Dean. You sent me this long ago.
I would be less enthusiastic than Dr. Gaddy about a .066" end of chamber wall thickness. We are blessed today to have lots of measurements with which to determine original factory numbers, and that's the lowest (of non-chamber lengthened) I've seen.
That said, it is difficult to get the wall thickness gauge pin exactly at the end of the chamber. And because the angle of the forcing cone is more acute than the external taper of the barrel, forcing cone numbers are often slightly more than the end of the chamber

[Dean Romig]

Thanks Drew - That’s the one.

And I’ve shot that gun at Skeet, grouse and woodcock a LOT with RST and my own low pressure reloads.





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