Percussion nipples impacting accuracy

[TexiKan]

Recently a few of us were discussing our scores at the range and I mentioned I was shooting high and to the right. A friend suggested that I change nipples. Now I have heard of changing nipples because of ignition issues but not because of accuracy concerns. In all the years I have been in this hobby, (since 1974) I have seen articles about lubes, patches, balls, powder, holding, etc. and how they can impact shooting accuracy but I cannot recall seeing anything addressing and documenting accuracy attributed to a nipple.

My friend participates at the annual Friendship matches and in the past remarked that a shooter there said he was not being accurate and changed the nipple on his rifle. Voila! Instant accuracy!

I would appreciate any input on how a nipple will impact accuracy. (not ignition) I also read the past thread on recommendations to replace a nipple. Again, what is the justification, specifically in regards to accuracy?

 

[Grenadier1758]

If the touch hole in the nipple is burned out or the top of the cone is deformed, you may be experiencing different chamber pressures. This lack of consistency is detrimental to accuracy.

A nipple is a cheap and simple change. Try it if you have been using the same nipple for a long time.

 

[necchi]

It's common and called gas cutting.
Part of the function of the nipple and hammer is to keep the small hole in the nipple closed during ignition,, all that pressure of expanding gases pushes the ball/projectile out of the bore.
That little hole still has a lot of pressure pushing on it and some gas does come out.
Depending on the load, sooner or later that small amount of gas begins wearing on the nipple hole and begins to enlarge it. Hammer blow back is a symptom of a worn nipple,, by the time that happens the amount of gas pushing the ball becomes erratic as gasses are escaping rearward out of the nipple and groups open up.
I find my nipples begin to wear after about 400-500 shots, changing inexpensive nipples bring the group back to where it should be.
A target shooter may replace nipples several times in a season, a hunter may go years with the same nipple.

 

[TexiKan]

I understood this to be one of the rationales, especially if the blow back causes the hammer to jump. Then it becomes obvious.

I am not sure exactly why I saved several used nipples other than one can become a quick backup if something happens to the one in the gun. They are not all the same manufacturer. Is the hole diameter for the ignition supposed to be the same for all makes?

Like changing lube, patching material, powder charge, etc., all are cheap adjustments yet I find most folks will do all of those before targeting their nipple as an issue.

 

[necchi]

Nipple manufacturers have a vastly different idea of how a nipple should be made, some are way different then others.

changing lube, patching material, powder charge, etc., all are cheap adjustments yet I find most folks will do all of those before targeting their nipple as an issue.

Yeah, and I've seen dog's chance their tail too. Some of them do it over and over and still don't figure it out.
I save my old nipples too and hand'm out freely to other competitors if theirs goes bad.
(just trying to help'm out)

 

[FrontierMuzzleloading]

yep burnt out flash hole causes accuracy issues. Always measure the flash hole every so often to check for enlarging.

 

[coloradoclyde]

I always wondered how people who say flash hole diameter affects accuracy, measure that accuracy objectively without incorporating a shooter variable or psychological bias.......

 

[TexiKan]

Agreed, Colorado Clyde. To me the variable seems to be minuscule and is comparable to a few more or less grains of powder in your measure, a dirty drum or snail restricting a little less, or how much one crushes the powder when one loads.

I considered giving my friend a new nipple and a used, worn out one and not tell him the difference other than to shoot some test shots to determine which is which.

As initially stated, I am also seeking any written documentation in the form of an article or research stating a nipple will make a significant difference in one's accuracy. I am still skeptical, and no, I am not going to purchase one of those platinum nipples!

 

[coloradoclyde]

I'm sure it does make a difference......As we know, any deviation or change in variable away from the standard of your load development will have an impact on accuracy.....whether or not it is actually noticeable, is debatable.

It might even make it shoot better.... :grin: :idunno:

 

[Idaho Ron]

Since I use conicals that tend to burn out nipples rather quickly I have documented it and I have even made a video about it. A man brought me a rifle that wouldn't shoot. We changed the nipple and it went right back to shooting where I thought it would. I change out nipples every year before hunting season. I see my shots tend to open up and hit a bit lower. I change the nipple for sure then.