A mate was at the range the other day and was hit by one of the nipples from his revolver.
Turns out it is of an age that they are starting to come loose from the rear of the cylinder...as in, come out at speed when he fires it.
One already hit him in the chest.

Anyone know of firms offering replacement sets?
He says that ideally he'll need the new ones to be a slightly larger pitch or thread to make up for the material lost over time.

Thanks for the replies so far

EDITED

I recently inherited an original colt army. I got nipples and other parts from S&S.

http://www.ssfirearms.com/

Some of the parts from Numrich didn't fit.

Lots of places.  First one which comes to mind is Dixie Gun Works.

Track of the Wolf. I put Colt into search, if you clear that and just search nipple you'll get 14 pages of nipples and accouterments.

If it's black powder related you can find it there.

Thanks for the replies and information so far

I've edited the main text as I have had a couple of updates

Try MidwayUK.com... What make is this 1851?? Uberti or other... Try local first. To prevent issues... UN  import laws etc... In the USA I would go to Numrich or Dixie Gun Works etc..

NOPE

Franchisee of that outfit kicked it to the kerb about FIVE YEARS ago to suck the Brownell teat - he can get bent, as can Brownells

UN Import Laws = never heard of such things - ITAR export, yes, but UN?