Useful Life of Nipples

[max]

I realize that accuracy starts to drop off when the flashole in nipples gets too large, but I was wondering if anyone has done a study on this. For anyone shooting offhand they probably wouldn't see the difference as much as a bench shooter.  Some say that the accuracy in bench guns starts to go south after as little as 100-200 rounds, and they're talking about roundball guns not cartridge guns used for long range shooting.

[northmn]

The biggest offenders are the long range slug guns loaded heavy.  Many ahve come to use platinum nipples to maintain any kind of consistancy in them as regular nipples can burn out in a match.  Roundball bench and rest shooters tend to use hotter loads also and should know.  Most of us shooting offhand use lighter loads that tend to save on equipment and people.

DP

[Dphariss]

I realize that accuracy starts to drop off when the flashole in nipples gets too large, but I was wondering if anyone has done a study on this. For anyone shooting offhand they probably wouldn't see the difference as much as a bench shooter.  Some say that the accuracy in bench guns starts to go south after as little as 100-200 rounds, and they're talking about roundball guns not cartridge guns used for long range shooting.

An inaccurate rifle is an inaccurate rifle benched or offhand.

Dan

[Daryl]

I've been using the same nipple in the 14 bore for about the last 1,000 shots. This stainless nipple is still in excellent condition with a tiny flash hole.

Nipple flash hole wear, hugly depends on pressure - the smaller the bore, the higher the pressure, the larger the charge, the higher the pressure, the heavier the projectile for that bore size, the higher the pressure.  Higher pressure wears out the flash hole more quickly.

Loss of accuracy is almost as noticable in offhand shooting as it is off the bench. Very minor changes that may be readily be seen off the bench might be overlooked when shooting offhand, but doubled group size should be noticed quickly by a good shot.

[Frizzen]

This is going to be hard to believe, but I am using the same nipple in my .58 Zouave that I put
in 1976. 34 years ago. It is a Ampco for the no. 11 cap. It still has the very tiny hole. I only
shoot 55 grs Goex FFF so pressure must be very low. Round ball also. Have shot this thousands
and thousands of times.  Also the nipple in my pistol is a Ampco. That was 20 years ago. Of
course I only shoot 17 grs of powder. I just don't shoot them out.

[Larry Pletcher]

The two shooting types that have trouble with this shoot higher pressures that round ball guns generate.  Round ball heavy bench gun shooters solve this with sealed ignitions. 

Long range bullet guns are the known for burning nipples too. Imagine the difference in pressures when shooting a 540 gr bullet with 90 grains  of Swiss as opposed to a 145 graing round ball.  In my LR bullet rifle I burned out a nipple in 10 shots.  A  platinum nipple solved the problem.  I recently heard that LR bullet guns will burn platinum nipples with large loads of Swiss fffg.  I will ask a couple of friends at Friendship if this is true.

I doubt if the typical round ball shooter needs to worry about burning out a nipple.

Regards,
Pletch

[Daryl]

On the contrary, Larry- at hefley Rondy, I replaced the nipple on a friend's underhammer rifle that had at least an 1/8" diameter flash hole.  I assume that nipple was 30 years old, but knowing Richard, he probably shot a lot of slugs from it as well as round balls throughout his time with it. The powder side of the nipple showed metal flow, ie: errosion as well. Quite interesting to see. Wish I'd kept it but think I tossed it out with the other garbage.  It appeared to be a standard steel nipple.  A closeup picture would have been appropriate here.

[Larry Pletcher]

Daryl,
You caught me off guard with a 30 year old nipple - never saw THAT coming.

Pletch

[Colonial Riflesmith]

In the old Marine Corps we had a saying, "It's not the dope on the gun, it's the dope behind it". If you miss your mark, it's not your equipment. The nipple on my rifle is about 20 yrs old with 1000's of RB through it. The deer don't notice the differance.

[Artificer]

At the 1996 World Championships of the International Muzzleloading Shooting Association, held in Wedgnock, UK - a burnt out nipple almost messed up one of our best woman shooters.  She was using an Ampco (sp?) nipple for over three years in an original percussion target rifle and the flash hole was burnt out significantly.   Her practice scores took a nose dive.  She was a seasoned competitor, with many medals to her credit, so it wasn't just nerves.  When we replaced the nipple in her rifle, the scores went right back up.  After that, we made a suggestion to all Team Members that they put a fresh nipple on at the start of every shooting season. 

[Daryl]

The nipple I spoke of, had a flash channel the same size as the top hole where the cap fits.  It was burn out to a straight hole right through.  No wonder there were never any cap fragments to remove before re-capping.

[Pvt. Lon Grifle]

FWIW my 2 band Enfield burns out a common steel nipple in about 250 rounds shooting a RCBS 58-500-M over 40 grains fffg Goex.  This is with a 1 1/2 K ball fit.  The stainless steel go near a thousand rounds.   

I know when my group enlarges that a new nipple is needed. I made a wire gauge to verify, and also have a tiny preferred size  wire gauge when I buy nipples by the half dozen.  No sense to buy them already burned out.

Lon

[Daryl]

While on the subject of nipples, I might add that at times, with light 82gr. charges with round ball, my 14 bore's caps don't expand much or at all and can be difficult to remove for re-capping and even loading the next charge due to trapped air inside the bore.  Due to this, I tried hot-shot stainless nipples, however in a shooting test, these 'vented' nipples proved less accurate than solid stainless nipples.

By carfeully tapering the outside top shank of the nipple with a file, I was able to remedy the sticking caps problem with the light loads and keep using the more accurate, solid nipples.

With heavy hunting loads, there is enough pressure leakage at the shot to open up the cap, allowing easy removal for loading, even on a brand new nipple. Such isn't the case with light charges.

One must keep in mind, that the large bores develope quite low pressure compared to the more common .45's and .50's. A 35gr. to 40gr. charge in either the .45 or .50 would give approximately the same pressure as an 82gr. charge in the 14 bore - about 1,150fps.

[cal.43]

normal steel nippels with plain base will be burned out after one hundred shots with my Underhammer
 .449 520gr Bullet, 80gr Swiss No.2 . Stainless steel nippels live longer and the best are those with tungsten carbide( Hartmetall) inserts.

[AZ Longrifle]

This might be off the topic, which has turned to wear and loads,
But, I own a flint lock from the 1750s that was converted to a percussion gun in the 1840s and it still has the nipple I got on it 30 years ago. It still fires fine and never has misfired.

[Daryl]

Nipples made back then, normally called tubes were of many different styles. Many were straight tubes, with an elarged outside section that had the threads & wrench seat. Many had inner flash holes were straight bored and of large size.

As Forsyth noted in his excellent book, the best nipples had a large hole at the top, but a tiny oriface at the bottom.  he made special note that some preferred to have the straight bored hole as they liked to see powder in the nipple. Forsyth noted that this type possibly slowed ignition and that with a clean system, the powder would be underneath the nipple, where it shoul be, to be instantly ignited by the flash of the white-hot flame and gasses blasting through the small hole.

AZ- I suggest that it would be a good idea to pull that nipple and check to see if it is straight bored, or is indeed choked like a normal, modern nipple & if it should be replaced (and saved for sake of authenticity).  Track sells nipples with a variety of thread pitches and sizes.

If the hole is oversize, or straight through, excess pressure will be allowed to blast up through it, disintegrating the cap's walls and hitting the hammer's nose upon firing, lifting it off it's seat and perhaps sending the fragments flying - some right towards your shiny eye ball.  It is best to stay on tip of the nipple's condition.

A worn out nipple will not hurt ignition so that is not a good way to decide if it's still OK.

[chapmans]

Most of the guys I shoot with use mule ear locks, after 200 shots we check the nipple, many times it's ready to be changed. Once my son was complaining that his shots were not going on call, I asked if he had checked the nipple recently, we pulled it and it was worn considerably and was oval in shape, after we replaced it he shot 35 consecutive 10's and X's.
  I have a friend that has been putting tungsten inserts in nipples, I have one that I've shot for two years and it's still good, it's not carbide but a tungsten electrode for welding, they have to have a .025" hole punched in them with an edm machine, they are almost as good as a platinum nipple.
   Steve Chapman

[Daryl]

Good mention on using carboloy, Steve - I've wondered if it might be useful, when reading about the very expensive platinums.  Getting a flash channel of small size in it would be a problem - for certain.

[William Worth]

How does one bore a tapered hole...?

[max]

I notice that at least one gunsmith in Germany supplies carbide nipples with his guns. You'll fine him listed under the "Underhammer Guns" thread in the Gunbuilding section. His website is www.dedinski.com/en/index_en.htm 

[Daryl]

How does one bore a tapered hole...?

The hole doesn't have to be tapered, just that it has a tiny hole next to the channel or powder in the breech.  boring the top, larger hole will leave a 60/120 degree taper at the bottom.  This taper will funnel the flash into the tiny hole in it's middle.  Tapered holes are usually made with reamers.