"Overload Proof"

[jefferyconnor]

This my new gun with Damascus barrels with this stamp. What year did Parker start this stamp? Was it coincident with a higher proof pressure? If so, at what pressure then, and what is the conversion to modern psi? I'd welcome any thoughts about what shells you shoot in Damascus guns and what pressure. Does anyone shoot store bought ammo besides RST in their Damascus guns, like Gamebore?

[Drew Hause]

Scroll down about 1/4 for an explanation of Parker Bros. proof testing
https://docs.google.com/document/d/1F2sQuPm05IE4VWYYnCkvuXmYEzQoWd_SQgaAfUOZEFU/preview

The 1893 Parker Bros Catalogue documented proof testing with Smokeless Powder in house
"Our guns are bored on the latest improved system for shooting Nitros, or Smokeless Powder, and all our guns are tested with some one of the most approved makes, and a tag accompanies each gun, giving the results of such a (pattern) test."

A Parker Service and Proof Load table was published in the 1930s and reproduced in the The Parker Story p. 515.
12g 2 3/4” shell Service Pressure is 10,500 psi. Definitive proof used 7.53 Drams Black Powder and 2 oz. shot with a pressure of 15,900 psi. The pressure was no doubt measured using LUP and modern transducer values would be 10-14% higher, or more than 17,500 psi.

LTC Calvin Goddard reported the same numbers in “Army Ordnance”, 1934. He wrote that Parker followed the SAAMI standards of that period: 13,700 psi proof, 9500 psi service for 2 5/8” chamber; 15,900 psi proof, 10,500 psi service for 2 3/4” chamber (by LUP) + 10-14% for modern transducer measurement.

"PARKER BROS. OVERLOAD PROVED" first appeared in 1925.

No ammo, of any pressure, should be used in a vintage gun, fluid steel or damascus, until after an evaluation by a specialist with the interest, equipment (bore scope and wall thickness gauge) and expertise to do so. If the barrels are free of defects and with adequate wall thickness (ignoring the recoil effect on the head of the stock) one should feel confident in using shells which reproduce the ballistics of those for which the gun was designed.

[Bill Murphy]

I shoot Federal Top Gun 7/8 ounce 1200 fps factory shells in my Damascus twelves as well as Remington 7/8 ounce 1200 fps loads. I almost trust Remington 1 ounce 1200 fps Game Loads in my Damascus 16s, but not quite. I use RST for my 16s and 20s. I have seen Damascus English tens prooved for 3 1/2" nitro shells, but I won't be shooting any factory 3 1/2" tens in Damascus guns.

[jefferyconnor]

I don't reload and RST does not have the UPS hazmat cert. like Cabela's and a few others have to ship ammo to Alaska. Thanks for the tip on Federal Top Gun, Bill. What other lower pressure factory shells do our members shoot?

It's my understanding factory average pressure is sometimes hard to get from the manufacturers.

[Brian Dudley]

All that most manufacturers will tell you is that their shells are made to Saami spec. That is the industry standard. That way if they change components here and there and pressures change, they are covered as long as they are under that threshold.

[charlie cleveland]

I would hate to have to pay for the shells in trying to blow up a Damascus or twist or any of the barrel steel made...if one got a penny for each shell that did not blow up a Damascus barrel and the other guy got a dollar for each shell that did blow up a barrel in a days time I would take a penny for each shell shot that did not blow up a barrel...at the end of the day I would have lots of pennys and the guy with a dollar a piece for each shell blowing up a gun would be in hole..bet he could not buy a cup of coffee at the end of the day... in my dads life time of shooting old guns he blowed up a set of stevens double barrels...it was a new gun...it was not the barrels fault...for some reason he pulled the shot out of the shell a 12 ga...it was Christmas time and he was shooting the blanks just making a loud noise celebrating Christmas...he said one of the blanks just barely sounded off and he took the shell out and put another shell in never looking down the barrel to see if a wad had lodged in the barrel...upon shooting it again the right barrel burst about 18 inches of the barrel....I still got that barrel that was 1947 year I was born... then I have shot all the old Damascus and twist steel barrel guns my daddy ever traded for and that was a lot of them old guns loose ans shakey and rusty...I was just a kid I did not know these old guns were supposedly dangeros....no telling how many boxes of high brass 10 ga 2 7/8 length shells I have shot in them old 10 ga clunkers....plenty of old high and low brass shells to in the 12 ga...only ever blowed up one gun it was a Remington 28 ga automatic fluid steel barrel...the day we traded for it I looked down the barrel inside it was a ring of rust about the end of the forearm..i told the guy who owned it about it he looked downed the barrel said it would be ok...I told him it mite burst he says I will put a new barrel on it if it does...next weekend my dad and I went squirl hunting the barrel burst on the 3 shot I fired....the man put a new barrel on it....charlie

[Chad Hefflinger]

what year does the serial number come back to on your gun? It would seem to me that you either have a very late Damascus gun, or the gun was returned at some point after 1925 to have some kind of work done to either the chambers or barrels by Parker Brothers and they felt he need to put he stamp on there.

[jefferyconnor]

This is a late gun, I believe mid-late twenties.

[Tom Flanigan]

The prudent thing is to have vintage barrels checked out by a qualified gunsmith. When I was a kid, I bought a few Damascus Parkers because that was all I could afford at the time. I shot them all with my hand loads, at around 8,000 psi and never had a problem. I shot a few seasons with a GH 20 bore with corn cob bores without any problems, which isn't to say it should be done. I guess I was lucky and as a kid, I didn't think anything could hurt me.

[Austin J Hawthorne Jr.]

I put alot of faith in the testing that Tom Armburst recorded in the Double Gun Journal several years back. That being said...while I prefer to handload my target shells to around 7500 psi...my #2 frame 12's and #1 frame 16's get a steady diet of NON MAGNUM factory shells during hunting seasons.

[Bruce Day]

This my new gun with Damascus barrels with this stamp. What year did Parker start this stamp? Was it coincident with a higher proof pressure? If so, at what pressure then, and what is the conversion to modern psi? I'd welcome any thoughts about what shells you shoot in Damascus guns and what pressure. Does anyone shoot store bought ammo besides RST in their Damascus guns, like Gamebore?

Started using stamp about 1926, however the stamp is merely an indicator of pressures that Parker had been using for years .

No.

10,500 psi service loads , 13,500psi proof loads. TPS contains a table of Parker service and proof loads.

Parker did not distinguish between composite and fluid steel barrels for pressure loading.

Your 12 ga was intended to shoot as a standard load 1 1/8 oz, 3 dram ( or DRE) loads . A 3 DRE load will run 1150 to 1200 FPS. Stated maximum loads for 12s are 1 1/4 oz , 3 1/4 Dram , clearly a stout load.

I shoot Remington, Winchester , Federals , Fiocchi , RST . All off those companies make 1 oz 2 3/4 Dre loads and 1 1/8, 3dre loads.

[Bruce Day]

Parker standard loads table . The measured speed is at 100 ft. Muzzle velocity would be higher and in the range of 1140 to 1240 or so.


This is a 1910 table for all Parker shot guns , composite and fluid.

[Stan Hillis]

Baschieri & Pellagri (B & P) have a 12 ga. load called the Comp One. It is a low pressure one ounce load. The pressure is 6530 psi. The Comp One 1 1/8 oz. load pressures are 8416 psi. These are published pressures. Both have a published velocity of 1160 fps. They are very soft shooting, but kill well. I can only use them in my external hammer guns. None of my sidelock or boxlock hammerless guns will shoot them reliably. I get misfires with them regularly because of failure to ignite the primers, from light primer strikes. There is something different about the rim shape and dims that lets the shell sit a tiny bit deeper in most chambers.

Don't ask me why the hammerguns will "light them off" every shot when the hammerless guns won't, but it's so. I haven't measured the firing pin protrusion on the hammerguns, but have measured it on several of my boxlocks that misfire with them, and too little protrusion isn't the problem. All are within specs.

But, I've shot up a couple flats of them and love 'em in the hammerguns.

[Drew Hause]

Here you go Stan
Competition One 24 gr. = about 7/8 oz. 1160 fps at 500 BAR = 7252 psi
Competition One 28 gr. = about 1 oz. 1160 fps at 560 BAR = 8122 psi
https://www.baschieri-pellagri.com/en/catalogo_tiro/cartucce+da+tiro/trap-skeet+training/1/index.aspx

Fiocchi acquired Baschieri & Pellagri last fall and apparently will produce the shells at their U.S. plant. I checked a few on-line retailers and none had any in stock.

[Stan Hillis]

Hmmm, those figures don't match the old ones I dug up. But, maybe they have changed since I last looked them up.

Thanks, Doc.

[Mike Koneski]

Baschieri & Pellagri (B & P) have a 12 ga. load called the Comp One. It is a low pressure one ounce load. The pressure is 6530 psi. The Comp One 1 1/8 oz. load pressures are 8416 psi. These are published pressures. Both have a published velocity of 1160 fps. They are very soft shooting, but kill well. I can only use them in my external hammer guns. None of my sidelock or boxlock hammerless guns will shoot them reliably. I get misfires with them regularly because of failure to ignite the primers, from light primer strikes. There is something different about the rim shape and dims that lets the shell sit a tiny bit deeper in most chambers.

Don't ask me why the hammerguns will "light them off" every shot when the hammerless guns won't, but it's so. I haven't measured the firing pin protrusion on the hammerguns, but have measured it on several of my boxlocks that misfire with them, and too little protrusion isn't the problem. All are within specs.

But, I've shot up a couple flats of them and love 'em in the hammerguns.

Stan, this has happened with various gun/ammo combinations over the years. One thing we have found here is some ammo is manufactured with slightly thinner rims and the shell will sit a few thou deeper in the chambers. That has caused some light primer strikes. If they were shooting at higher birds it didn't cause any misfires but if your gun was below horizontal or swinging fairly hard it would allow the shell to settle in lower in the camber. Maybe this will answer your question? Hope it helps.