Measured strength of a cap

[Charlie Hahn]

In a past life, I worked with various Primary Ignition mixes. I knew we would measure flame, and pressure waves, but I didn't pay as close attention as I should have during this time as the nerds where looking for such small blips I didn't see the value. So, I would like to know if someone in our organization has any data on how much power each cap has?

I know we all use the term "hotter caps", and I believe it is some visual thing or audible feeling.

Based on some old information I believe there is a flame value, and pressure.

Any input is welcomed.

Thanks

Charlie Hahn

[Jim_Burgess_2078V]

A study of the relative power or "brisance" of the various available percussion caps would be very useful. I have not seen any relative ranking for caps but I have seen some data for modern primers for shotgun and metalic centerfire cartridges. Federal and Winchester seem to enjoy a reputation for producing relatively hot primers while Remington and CCI primers are comparatively weaker, necessitating higher powder charges to achieve comparable ballistics.

Brisance may be subject to some variance by manufacturing lot, storage conditions and weather conditions at the time of use. When I first started shooting my Shiloh Sharps carbine in 1978, I used German (RWS) caps marketed by Navy Arms and had no problems. When the RWS caps began being sold in less than air-tight plastic containers I started having hang fires and misfires. Switching to the hot CCI 5-wing caps, my Sharps continued working perfectly. When those caps became unavailable I used up some old tins of Brazilian caps which also worked well. I started using the wingless RWS caps at the Spring nationals. They go bang but my Sharps scores have plummeted which I believe to be partly due to slower ignition. When I deplete my supply of wingless caps I may have to retire my Sharps and go back to my Parker Hale musketoon if no hotter caps become available.

Jim Burgess, 15th CVI

[Jim_Burgess_2078V]

A study of the relative power or "brisance" of the various available percussion caps would be very useful. I have not seen any relative ranking for caps but I have seen some data for modern primers for shotgun and metalic centerfire cartridges. Federal and Winchester seem to enjoy a reputation for producing relatively hot primers while Remington and CCI primers are comparatively weaker, necessitating higher powder charges to achieve comparable ballistics.

Brisance may be subject to some variance by manufacturing lot, storage conditions and weather conditions at the time of use. When I first started shooting my Shiloh Sharps carbine in 1978, I used German (RWS) caps marketed by Navy Arms and had no problems. When the RWS caps began being sold in less than air-tight plastic containers I started having hang fires and misfires. Switching to the hot CCI 5-wing caps, my Sharps continued working perfectly. When those caps became unavailable I used up some old tins of Brazilian caps which also worked well. I started using the wingless RWS caps at the Spring nationals. They go bang but my Sharps scores have plummeted which I believe to be partly due to slower ignition. When I deplete my supply of wingless caps I may have to retire my Sharps and go back to my Parker Hale musketoon if no hotter caps become available.

Jim Burgess, 15th CVI

[Charlie Hahn]

Thank you for your reply. I was planning to make a fixture to do the testing on some practical level. I believe I need two tests, one for force where I can mock up a short section of a barrel and a cylinder and measure distance, the next would be a perforation test to do an un-pressurized test of flame. I expect the flame test would need to have one and then two right angle turns to simulate a musket bolster, and then other guns that have two turns, (Maynard & Sharps).

I read somewhere that to old marksman wanted a primer that offered a heavy flame with low pressure, (ALCAN caps did this).

With the primer supply going through some bumps right now, I want to see if there is some practical way to consider CCI magnum pistol caps on a musket with a hammer cup modification. This is planned to be one of my winter projects.

If you have any other ideas, or would like to discuss this I would welcome that chance.

Thanks

Charlie Hahn
410-208-4736

[MR. GADGET]

One of the things I did when CCI changed from 6 to 4 wing is to test the caps.
I was talking to CCI and one of the guys that heads up the Cap line at the NRA show a few years back..
He would not tell me that they change but kept telling me they were made the same other then 4 vs 6 wing.
To shorten the story I ask him if he wanted to come to my place to do some testing and he said no but said he would send me a tube for free to test.
I use a crono and a few other tests on loads..

The test that told the real difference was a very easy barrel PSI test in a way.
I used a wood rod, and would angle the gun in a mount so the rod would move but not shoot out the end of the barrel on any caps.
I tried several caps with the test and what I found on a clean barrel, the rod would move free every time in the bore for the test.
The 6 wing caps on the gun in a vise would move the rod about 6-8" more then the 4 wing caps every time. Tested 4 then 6 then 4 then 6 so the gun would have the same use for every test.
After calling the guy back and talking to him, they said that they have a way to measure PSI on a section of barrel like they do any other round, and that my rod test was in fact correct showing the primming to be better on the 6 then the 4.
He added that if it caused a problem with the live fire guys they still have the compound mixture and could change back.
Sales and time would tell.....

So that was what I found.
I also found some of the German 4 wing to be lighter then the CCI 6 wing.
Early german in the tins were hotter.
I use the wingless now but still have some 6 wing left that I save for my sharps.
I have enought to go a few more years then I will need to start looking and testing to see what is out there.

Just my 2 cents.


BTW, that type of test using the wood, comes from a old timers test to see if the hammer is hitting the firing pin on a gun good.
You could stick a piece of wood in a gun like a german K98 and see if it shot it out, if it did then the spring was good to go and the FP was intact. As it was common to cut the FP on a lot of bring back war guns.
So I said why not for a BP gun and caps.
Use a 1/2 wood dowel ( or size to fit the gun), good to test. Drill and add weigth if needed for shorter gun. Just make a mark so it is 1/2" to 1" in front of the flash hole.

[Charlie Hahn]

Thanks,

That is similar to what I was going to do to test pressure. I don't need a number, but a comparator which is what you have done. The next part is flame. This is an over looked part of the equation as I am always looking for a better cap for my Sharps. As you, I have several years of CCI caps. I am interested in the mag. CCI pistol caps if they don't revert back to the more active mix and a four wing configuration.

The one reference book I am working out of had a modification the shooter did to his hammer to force more down through the barrel on low pressure high flame caps. They also used a large flash hole which is different than what we do.

I have a bunch of nipples with no inside. I plan to do several things, one is an angle fire timed nipple, the other is a musket nipple to use a pistol cap, straight, and angle fire, then both with a pocket hammer and see what happens. I am avoiding an angled path for the Sharps, but may have to enter this into the mix.

I hope CCI makes all of this not necessary by make a better target cap.

Thanks again for your time and detail

Charlie

[RangerFrog]

Charlie

About 15 or so years ago, the late Charlie Dell (of schuetzen fame) got interested in the same thing only for large and small primers. He built a sort of ballistic pendulum with a sort of fan blade to "trap" the power of the flash and convert it to angular motion on the swinger... I'll try to find out what happened to it after he passed away.

Froggie

[R. McAuley 3014V]

In 1848 Frankford (then Bridesburg) Arsenal was given the task of developing the manufacture and testing of the percussion cap, and from then until 1976 the arsenal served as the nation’s principal developer and manufacture of small arms and artillery munitions, and except for World War II had been the sole producer of military ammunition for the United States from 1876 to 1961. So it sounds like for what you are seeking that perhaps a visit to the Rock Island Arsenal Museum may be in your near future since it appears that was where the precision instruments produced at Frankford Arsenal were sent. You may find some of the links below useful as well.

http://memory.loc.gov/pnp/habshaer/pa/pa1400/pa1439/data/pa1439data.pdf

http://www.sil.si.edu/smithsoniancontributions/HistoryTechnology/pdf_lo/SSHT-0011.pdf

http://www.dtic.mil/ndia/2007smallarms/5_8_07/Busky_520pm.pdf

http://books.google.com/books?id=vxEZAAAAYAAJ&pg=PA159&lpg=PA159&dq=Frankford+arsenal+museum&source=bl&ots=1QsJhkI75h&sig=U8-zluRu8fUI_OxVqUdW21W0Qt8&hl=en&sa=X&ei=TnikUNGiL4rc8ASex4HwCg&ved=0CD4Q6AEwAw#v=onepage&q=Frankford arsenal museum&f=false

http://books.google.com/books?id=V54UAAAAYAAJ&pg=PA78&lpg=PA78&dq=Frankford+arsenal+museum&source=bl&ots=5ycmdxQnxN&sig=NuxdqIdCqv_BwxxlMC8BAABmnI4&hl=en&sa=X&ei=D3ukUNbLHoKg8gTMxoDABg&ved=0CEAQ6AEwBDgK#v=onepage&q=Frankford arsenal museum&f=false

[tony 1st regt]

tell your friend at CCI to make the 6 wing caps again, they are the only cap that provides 100% sure fire in my sharps.

[Jim_Burgess_2078V]

I'm glad to hear I'm not alone in having ignition problems with my Sharps. At the 2011 NRA Convention in Pittsburgh I had the opportunity to speak with a CCI representative at the ATK booth (parent company of CCI) and expressed my dissatifaction with the discontinuance of their 5-wing caps. I learned the reason for the change to weaker 4-wing caps was a lawsuit filed by a dumb re-enactor who wasn't wearing eye protection and lost his eyesight due to a cap fragment. I was also aware the National Park Service had banned the use of 5-wing caps due to the potential for this happening in musket demonstrations. Evidently ATK considers the re-enactor/living history market to be more lucrative than competitive shooting and prefers to cater to the blank firing crowd. The gentlman I talked to, who admitted to being the engineer responsible for designing the new caps, gave me his card and encouraged me to at least try the new caps. I now have and I wasn't impressed.

Perhaps we need to start a petition to CCI urging them to resume production of hot caps. Sharps and Maynard shooters should unite in this effort. The caps need not be 5-wing which would have an increased potential to fragment. 4-wings are fine as long as they increase the brisance back the way it was. To keep their lawyers happy they would no doubt have to market them with a disclaimer that safety glasses must be worn and/or a warning that they should not be used with blanks. They would likely be more expensive than the re-enactor caps but that will probably help discourage use by re-enactors.

If you wish to directly contact the man at CCI, his name is Bret Olin (email: bret.olin@atk.com). However, the remanufacturing/marketing of hot caps will be a decision made at upper management levels and that is where we need to direct our collective voices.

Jim Burgess, 15th C.V.I.

[RaiderANV]

A very uneducated guess............I'd think the 4 wing even with the hotter mix should stay together as it's a lot more metal over the 6 wing concedering the size of it.

[Jim_Burgess_2078V]

For those who would like to contact Mr. Olin at CCI/ATK, the email address above is incorrect. There are 2 "t"s in his first name. The correct address is: brett.olin@atk.com . Commander Phil Spaugy deserves high praise as he has already drafted an email to Mr. Olin on our behalf. It still might take a flood of emails to get CCI's attention.
Jim Burgess, 15th C.V.I.

[Phil Spaugy, 3475V]

As Jim indicated, I emailed Mr. Olin today, and I did receive a read receipt from him. I will keep you all posted if he responds and what that response might be.

I also send a message via the CCI Facebook page, which might be a good avenue for individuals to express their interest in a hotter cap.

https://www.facebook.com/CCILeader?fref=ts

CCI website is below, they have a contact page, which I used and received a rapid [and I am sure canned response] that my request would be passed on to their Products team. Feel free to contact them.

http://www.cci-ammunition.com/

If I can get a someone from CCI to respond with interest I will discuss the option of doing a limited run for our membership using their current 4 wing cap with a more powerful priming compound.

Phil

[Gary B]

Hey guys, dont forget the Galleghers. The 6 wing are the only caps that give a reliable ignition for my Gallegers too.
I'll sign the petition !
Thanks,
Gary B.

[Bullseye54]

Where can I purchass caps in CT.. The hazard shipping fee is a killer!.. Thanks Joe

[R. McAuley 3014V]

One book that you may find of use is the 1999 reprint of the British War Department (1929) Textbook of Small Arms, wherein features one device, a “side-pressure gauge” or “Pressure Recorder” devised by Mr. G.P. Thring, of Cambridge (1921). A rather similar device developed by U.S. Army Ordnance Captain (afterwards General) T.J. Rodman (under title The Text Book of Gunnery, 1857), and with certain modifications, was in daily use for ordnance under the name of a “crusher gauge” used in ballistics laboratories to measure peak internal ballistic pressure lasting only a few hundredths of a second.

However, Rodman’s device being too large to fit into the cartridge case of a rifle, was subsequently modified by French physicists Vieille and Sarrau (1883) and Charbonnier (1892) and adapted to small arms. In 1895 it was independently invented by an arsenal workman that by 1929 was commonly employed at Woolwich Arsenal under the name of the “Ordnance Factory oiled-case method” for use with the .303 service cartridge. This device is similar to Nobel’s “crusher gauge” (1868) which is further explained in the link below in Colonel Pashkievitch’s Internal Ballistics (1892):

http://books.google.com/books?id=0qg_AAAAYAAJ&pg=PA64&lpg=PA64&dq=Rodnam+ballistics&source=bl&ots=txCG7oScl1&sig=YCnsqf3ZU8HYP1GgjoKUo1LATEk&hl=en&sa=X&ei=G1-uUNX9IpSi8gSSjIHACQ&sqi=2&ved=0CDAQ6AEwAQ#v=onepage&q=Rodnam ballistics&f=false

But I should mention these gauges were primarily concerned with measuring the internal ballistic pressure as a result of the propellant denotation rather than the pressure exerted by the percussion cap primer alone, even though, theoretically, the same gauge ought to suffice for measuring the pressure created by the percussion cap. Note, there seemed to be no observations made anent determining how “hot” one percussion cap was versus another. Though they give a chemical formula for the primer composition, it seems no tests were conducted to compare one primer composition with any others.

For the most part, once a suitable chemical primer composition was found, most of the experiments carried out on the percussion cap (and later rifle and pistol primers) were conducted on the firing range, and were seldom concerned with determining the cap’s peak pressure or heat when detonated. Most texts on modern cartridge reloading stress the safe handling of primers and how to recognize the effects of excess pressure either when loading primers (to avoid crushing) or other problems caused either by excessive headspace or propellant. The topic of primer composition may be for a chemist to best determine and offer their recommendations. But a chemist could determine the burn rate and the specific heat of different primer compositions, and this may answer your questions regarding the potency of the two types of CCI caps.

Below is another link to a text on Interior Ballistics containing some formulae on the same topic as well as the “Theoretically Determination of the Temperature of Explosion of Gunpowder” and other experiments that might allow you to isolate some variables relating to the cup pressure of primers, and hence adaptable to percussion caps?

http://archive.org/stream/interiorballisti00ingauoft#page/32/mode/2up

Refer to the comment below anent the Borland Cap Tester, and this will likely suffice for your original query: how to measure the strength of a cap.

[Southron Sr.]

One of the problem I noted with the CCI "Hot" caps is that the copper or brass mixture that the cap was made out of seemed to be "soft" and prone to fragment.

First of all, IF CCI were to re-introduce their "HOT" caps they would be will to make them like the RWS "Wingless" musket caps as simply there WAS LESS material to go flying IF a Wingless cap frags. Also, of course the body of the cap should be made of stronger brass.

I am still requesting that everyone contact their Regional Commander and ask the BOD to consider writing a letter to the president of CCI (or ATK) requesting that CCI re-introduce their "Hot" caps.

I am still of the opinion that a Formal Request from the North-South Skirmish association would carry a lot of weight with the managment of CCI.

[R. McAuley 3014V]

In William Wellington Greener (1910) The gun and its development, Greener elaborates on Borland’s Cap Tester (page 312-14): "In shooting, so much depends upon the uniformity of the ignition that the cap-testing apparatus devised by Mr. Borland, of the “E.C. Powder Company, is a distinct boon, and more than anything else will lead to the standardizing of caps for various arms and special explosives. The details of the early experiments to determine the best methods of ascertaining and recording the strength of the caps are too full to be given here; they, as well as descriptions and illustrations of the machines, are contained in the Sports Goods Review, Vol. IV. The sensitivity of caps is measured by the height from which a dead-weight of 2 oz. must fall to detonate them properly. Twelve inches should be sufficient, but some caps require a 30-inch fall. The shape of the striker affects the issue considerably; the ogival head will detonate with less weight than the hemispherical point.

Three methods of observation are usual to determine whether the detonation is efficient. The sound of the explosion—there is no possibility of mistaking a miss-fire or fizzle. The flash may be received on paper, and the extent of the charring and residue afford the required indication. The explosive result may be measured. After various experiments, the means decided upon as being the best for the purpose consist of a steel bolt which, by the force of the explosion of the cap, is driven to compress or cut off soft lead plugs. The bolt, or plunger, carries a knife or chisel which rests upon a plug or small cylinder of lead, the 2 oz. weight is held by an electric magnet, and on the current being severed, falls upon the striker in the hinged cap over the cylinder in which the cartridge case, or cap, in a suitable holder is placed. The explosion acts upon a pistol connected with the bolt or plunger, the chisel edge of which is driven into the lead plugs placed in the anvil below. With the help of the chronograph the machine may be made to measure the time elapsing between the fall of the weight upon the cap and the movement of the piston, thus giving the time occupied by the explosion of the fulminate.

To determine the weight of the blow given by the gun-striker, Irvine’s gun-lock tester is used. It is based on the principle of notching lead discs, the blow of the striker acting in lieu of a weight and driving the piston against the lead disc. The leads are contained in a dummy cartridge case, the piston occupying the place of the cap; a micrometer screw gauge fits into the fore part of the instrument, and the readings of the depth of the notch, produced by the fall of the hammer, may be read as foot-ounces, since the drop is calculated as three-fourths of an inch, which is a 16th part of a foot: 2 lbs dropped 3/4 inch gives 0.028 indentation; 10 lbs, same distance, 0.060; and 14 lbs, 0.07 of an inch."

Please be kind to direct any of your other questions to Messrs. Greener and Borland.

In the trade journal Arms and Explosives (No. 132, Vol. XI, September 1903) "Lectures to Young Gunmakers (XXII – Cap Testing)", pages 138-40, likely provides as much of the details concerning Borland’s Cap Tester as the Sports Goods Review might would have contained, and is available via the link below:

http://books.google.com/books?id=c_ZYAAAAYAAJ&pg=PA138&lpg=PA138&dq=Borland's+Cap+Tester&source=bl&ots=HMFj6TEFbG&sig=iaJnL3_91BG7tqBIfR2HBGibHSY&hl=en&sa=X&ei=r_e3UJLkFJCa9QSbvoCADw&ved=0CCsQ6AEwAA#v=onepage&q=Borland's Cap Tester&f=false