.024 (24 THOUSANDTHS) DAMASCUS
 

I'm looking for opinions on the shooting with low pressure loads of Parker damascus barrels with no apparent flaws but only .024 thickness at their thinnest. Both barrels are the same and both apparently were polished inside.

Thanks.

Jerry, have you meticulously measured the barrel walls yourself up and down the tubes and all around them and determined them to be .024" at their very thinnest points anywhere on them?

Incidentally, .025" is the standard minimum we hear of when discussing the 12 gauge but smaller gauges would likely need thicker barrel walls.

Be careful. There is low pressure and there is low pressure. I shot one that was .020 at the thinnest. It was ten gauge, and I picked a load rated at 4800psi. Everything went fine, but I was not comfortable with it.

Dave

Dean,

I have not measured them; the owner did,so they may be worse than reported. I do not want to make a costly and dangerous mistake in their purchase.

Thanks.

I had this discussion yesterday with David Trevalian. My personal standard has always been 25 but he tells me he has submitted dam barrels for London proof down to 20 and had them pass. I also thing all dam is not created equal and the history of the gun and any past abuse is important. JMHO
David

Where the thin area is makes a huge difference in "go--no go". If it's near the muzzle then the thin wall is probably a non event. If it's close to the breech then you ought to reconsider shooting it. I have a 16 gauge Lefever DS with steel barrels and they measure about .024 12" ahead of the breech. I'm shooting RST's in it but must admit being a tad queasy. However, three gunsmiths of national renown separately told me not to worry about it........but I still do.

My personal standard of safety is for the first third of barrel length from the breech must be of sufficient thickness as to be a non-issue but forward of that is, in my opinion and for my own purposes, less significant but I will not post the thickness of barrels I have owned and shot in the past.

Jerry,
There are many philosophies on the subject. At best those barrels are borderline for safety. I shoot mostly Damascus, and my advice is be patient and keep looking. There are plenty of guns out there with good stout barrels.

Dave

Where did this .025 MWT dimension come from? Has there been some recent documented definitive testing done to arrive at that number or is it someone's personal minimum?

The reason I ask is that I was informed via direct correspondance with Michael Lynch, the chief inspector of The Birmingham Proof House (who undoubtedly has more experience in this regard than any other person or entity that I'm aware of) that they inform their customers only if the MWT falls below .020---even though the gun may have passed proof below .020. So, it would seem that .020 is The Birmingham Proof House minimum for concern as long as load pressures are kept under for which the barrels were proved.

Now having said this, we all know there is more to it than just MWT, like condition of the bores, pitting, dents, dings, previous repairs, etc. that can affect the strength of the barrels.

Greg, I have read the same "safe at .020"" too and don't doubt it taking into consideration the qualifiers you pointed out but I'm just not comfortable with giving this topic a "blanket coverage" because without examining such barrels personally I think it would be irresponsible to do so.

Proof House
 

I think part of the key here is that the Proof House Proof Tests. So they do not merely pass the gun because it has 20 thou, they shoot it with a proof load and see if there is enough THOU to avoid POW. :eek:

And, it does seem like I have seen more pressure problems with small gauge guns than with larger bores. Don't remember enough physics to recall if a cylinder of a larger diameter would be stronger than a cylinder of a smaller diameter for a given pressure.

OK, so the measurement was made by the seller. That is not the way this game is played. The way the game is played, rule #1, is "You buy a Manson wall thickness gauge from Brownell's for about a hundred bucks, measure the wall thickness yourself." Only then do you buy any old gun for more than about $300.00. If my measurement showed .024, I wouldn't be interested in the gun.

Barrel Thickness
 

I believe the .025 number comes from a hoop stress calculation by Oscar Gaddy.

Best, Austin

Add to the FAQs?

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 the 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.

Christopher Austyn Modern Sporting Guns
"There is no legal minimum thickness for a shotgun barrel, although the British Gun Trade Association recommends 20 thousandths of an inch as a general minimum."

Nominal Parker Barrel Thickness
 

We measured the outside diameters of several Parker barrels to attempt to generalize barrel taper. These tables will appear in the Spring Issue of Parker Pages.
Parker barrels are hand filed, and the outside of the barrel is not concentric with the bore. One cannot simply subtract bore diameter from outside diameter to determine thickness. However, examining several barrels and subtracting the nominal bore diameter allows one to estimate the nominal thickness the filers were trying to produce.
Analysis of 22 twelve gauge barrel sets, including three sets weighing less than three pounds, indicates the nominal minimum barrel thickness at 24 inches is 1/32 inch. Eccentricity may cause portions of the barrel to be thinner than this. Minimum nominal thickness at 18 inches would be about .050 inches.
If those of you that have barrel thickness gauges would like to make up tables of actual measurements, we will publish them in a later issue.

Best, Austin

Bill,

I had planned on that (already have a gauge) but knowing .024 is borderline, I was only seeking second, third, fourth, etc. opinions before I wasted the time to get the gun in hand. That's the opinion I was looking for, that if it was .024 you'd pass on it every time.

Thanks.

That's sure not my opinion. Once again, it's a matter of where the .024 is. If it's in the last third or even the front half of the barrel I wouldn't worry about it at all if the rest of the barrel is solid. I think a whole lot of Parker guns would be tossed aside from "thin walls" if the owners really knew how thin they are. But many of them were originally struck quite thin and they've gone a hundred years with nary a problem. Why not another hundred. Find out where the thinnest portion is and then make your decision.

I was told by a gunsmith who deals with a lot of refurbished English guns that the London proof house limit was .018". Anyone ever seen that number used?

I have one with .730 bores and is in the .023-.024 range if not very close to original... maybe barrels where re blacked..... maybe bores where polished it's a 1895 gun, bores ran on the large size then.... I haven't seen any info of original bores being under .729.... so if not close to factory where was the metal removed?
These are decisions each individuals will have to make but I think the gun has to be looked at and assessed.
Rich, we have a smith in the area that apprenticed and worked in England and he has mumbled numbers in that area.

surly those barrels on parkers struck at 3 lbs and under has to be pretty thin...a gun weighing 6 lbs and under cant be very thick or it will start weighing more trhan 6 lbs... just my opinion..... charlie

I shoot a 6 pound 4 ounce Sauer ten gauge with wall thickness no less than mid thirties. There are many tricks that gunmakers use to lighten guns. I agree with a poster who correctly modifies my opinion to state that .024 up in the north end of a barrel is no big deal. I just wouldn't like it in the hands on section of a Damascus barrel.

Interesting thought. Has anyone seen any evidence of erosion of the holes of a heavily-shot ported gun?

Big D, My Browning Citori Trapgun has 67702+ counted rounds through it.
41244 through the top barrel and 26458 through the bottom. No signs of errosion.
The plastic and carbon that collects in the ports probably acts as a protection?
And the gun has not had one mechanical failure I might add.
A modern day "Old Reliable"? :duck: :)

I have several ported guns - and one I have shot at trap for several decades. There is no sign of anything.

By the way - "Porting" and "Pitting" are TWO entirely DIFFERENT issues. Ports do NOT constrain pressure, but rather deflect pressure to the advantage of the shooter. Pitting tries to CONSTRAIN - but given PRESSURE - could erupt the barrel when pressure is at it's peak - i.e. and n.b. - which is not the the advantage of the shooter, should he/she be missing a few fingers when the pressure is more than than the barrel wall thickness might provide...

Porting and pitting - again - are two very different issues with two totally two different effects and outcomes.

John

John, you have brought "pitting" to a whole new high. In the future, when I buy a pitted Parker, I will drill those little buggers out to relieve the pressure. Is this a great forum, or what?

Hi Bill,

Not to take the topic off topic, but I think someone said "pitting" is like "porting"...? Which - well - isn't exactly right..

Should I just delete my post?

;)

Best to you!

John

And oh - yes... I forgot to add... Please do drill those pits out... It will make the barrel lighter too...

:shock:

I love this forum... So much to learn and do....???

Best to ya'!

John

Blame me for the porting entry. I realize that porting ain't pitting, and probably should have started a new thread, but the porting picture triggered my small brain. It occured to me that that hot gas venting thru those small holes over time might create havoc. Sorry for the diversion

No, John, please don't delete your post. It adds some technical aspects to the voodoo of barrel pitting.

As long as you don't delete yours? Not sure about any "technical aspects" about pitting that I might have added - but - if you say so, it must, well, be true?

Gawd - I love this forum... So many are so right over so much - and all at the same time..!! Who would have guessed???

John

bill did i read the post right 6 lbs 4 ounce 10 ga......lightest 10 ga by far i ever heard of...what loads do you shoot in it and what do you hunt with it..... charlie ps lighest ten that i have is 8 1/2 lbs and the heaviest is 10 1/4 lbs

I have a 26" 5# 11oz Linder Daly 12ga fwt on the way here soon. I'll be interested in seeing how they made it that light. Hope it wasn't by honing the bbls to beer can thickness...

richard them 12s that light have got to kick like youve been hit with both back feet of a big mule...should be a pleasure to tote ...weighed my 20 ga today on my old scales it weighed 5 1/4 lbs.they could be off a couple ounces.got to get me some of those digital ones....

If it is like my Lindner Daly FWT - you'll be just fine. No beer can barrels - as I shoot it all the time and - and, as a huge PLUS - the barrel walls at their thinnest point are well above the thickness - as the subject of this thread..??

It also doesn't haven't any ports/pits in the bore I'll need to drill out?

But - what the hell do I know?

Enjoy your new Daly Featherweight! They are wonderful...

John

I think yours looks a just tad cleaner than the one I'm getting John. I am looking forward to trying it with lighter handloads on ruffies. Should be perfect. The workmanship on the Linders is exquisite. My normal wt Linder 12 has pretty stout bbls for a short and relatively light gun. Seems a touch more barrel heavy than most Parkers. I see your triggers are even bent correctly for a right hander... Nice gun... Could I by any chance 'borrow' it for a while??? Just a little while?? Not for long....

Hi Richard!

You are more than welcome to borrow this little Daly any time..?? There is a hitch though?? You can only take delivery in person?? And yep - like all my guns, you are free to borrow them whenever..? For example - Scott has my little DH DAM, Pete has my AAHE vent rib, Dean has my DHE 20, Bob has my little VH 20, Scott has my Nikon D200, Danny has my.... Oh wait - sorry..??

As for the triggers - yep - they are articulated for a RH shooter. And if yours is like mine - it will feel like a wand in hand - and shoot even better..?? I'll post more from this little Daly - but I think the one you want to "borrow" is a little Diamond Quality Lindner Daly I have stashed away. I've never posted pictures, but - she is a beautiful little 12 GA. That's the one you want to "borrow", I think??

And yep - a wonderful little woodcock and grouse gun...

Please post some pics of your FWT when she comes home to you, OK??

Best to you!

John

Yeah! The Diamond grade! Yes! That's the one I really meant! Love to borrow it. I'll be right over.... leave a light on...

Just to help establish a "benchmark" of sorts..... with objective data. Yesterday I measured a damascus Francotte of 1896 vintage. Gun is all-original with 18.4mm bores (.726/.727" as confirmed by my Galazan bore gauge). It's damascus is the chain pattern type, and the exterior barrel finish is original and in pretty good condition. Minimum walls are .031/.032" as measured 8-9" back from the muzzles. That's the thinnest measurement anywhere on the tubes. The walls were measured with a Galazan wall gauge - the heavier bench model with vertical posts to hold the barrel and the dial indicator.

This barrel set weighs 3 - 10.7. And the gun weighs 7 - 5. While I understand that a Francotte is not a Parker, the data reported here will give an idea of what another quality manufacturer put up on its guns.

This thread reminded me of the first damascus gun I purchased from a gent who seemed to know what he was talking about. It's a Syracuse Arms gun that supposedly had been "lightly honed" by a gunsmith sort I had heard of. I didn't have a wall gauge at the time, and a short bore gauge (since replaced) showed the tubes to have irregular I.D.'s. Whatever.... Then, months later when I sprung to buy a better/longer bore gauge, and also a wall gauge, I discovered there are multiple locations on the tubes where the walls are 16 to 22 thou thick. I suspect it was "honed" with emery cloth on the end of a rod, turned by a drill motor. The SAC gun now sits off-line in my safe, with a paint marker UNSAFE warning on her barrels, while I look for another barrel to fit to it. Lesson learned.

Since then the bore gauge travels with me whenever I think I might find a gun, and the wall gauge is always in the vehicle at the larger shows and shoots.

Frank

Yeah, Charlie, the little Krupp barrel Sauer ten weights 6-4. I usually shoot RST 1 1/8 ounce loads at preserve pheasants with it. Once I accidentally loaded a 1 5/8 ounce Super-X paper and fired it at a skeet bird. It almost killed me. I won't make that mistake again. It is 26" bored tight modified and full, so I can wait for everyone else to shoot before I have to commit to a bird. I still don't see the trick they used to get the gun so light with safe barrels. The gun is just about identical to a Daly Featherweight.

Expiriment
 

I have not loaded a pdf file before; this is an experiment. This excel file shows barrel dimensions of a gun we did not include in the analysis of barrel taper for Parker Pages. It is a pretty beat up and cut barrel gun; but it is the lightest lifter 12 I have seen.

The breadth of the barrel set and the diameter of a barrel vs distance from breech is tabulated; from this the void between barrels and the nominal barrel thicknes at that point are calculated.

These barrels look and feel paper thin; but they measure .040 at the muzzle.

Best, Austin