Questions on touch hole liners' service lives?

[Naphtali]

I have been informed that best-quality makers such as Nock, Manton, Mortimer, etc. used touch hole liners that were platinum lined to resist heat erosion. How long did such liners last in terms of shots fired? Was there a significant difference in longevity between fowlers and rifles?

Are platinum lined touch hole liners manufactured currently? If they are, by whom?

Regarding Chambers White Lightning liners, what would be a generally accepted average number of sporting rifle shots until one of these touch hole liners need be replaced? Is this replacement a skilled job, preferably accomplished by a gunsmith?

I suspect durability-longevity was dependent upon both powder charge used and stress of combustion - that is, modestly loaded rifles' touch hole liners will last longer than a load intended for a flintlock Hawken used to regularly shoot bison at 150 yards.

[T*O*F]

Are platinum lined touch hole liners manufactured currently?

That's two linings, or a lined liner, which was not the case.  The entire liner was made from platinum.  Platinum didn't used to be a precious metal as it is today.  It was cheaper than silver, and also used for lock and barrel inlays.

Today, the cost would be prohibitive and I know of no one making them.  On the other hand, platinum lined nipples are used in long range bullet guns, which will burn out a standard nipple in as few as 10 shots.  They have a small piece of platinum wire inserted into the nipple, through which the flash hole is drilled.  They are currently $85 each.  These are custom made nipples, not just standard nipples with a hole drilled in them.  The design is different.

[SCLoyalist]

Regarding Chambers White Lighting liners,  here's what Jim Chambers said when I asked about whether to increase the diameter of the hole to 1/16" inch after installing or leave it as manufactured:

"For maximum accuracy you should leave the hole as installed and change the liner once he hole enlarges past 1/16" which usually occurs after apporximately 3000 shots.  For maximum ignition without any misfires I normally enlarge the hole to 1/16". I don't do much serious target shooting, so I'm more interested in having100% ignition than in having pin point accuracy."

I'd interpret that as life of a WL THL to be somewhere around 3000-6000 shots, depending on whether you enlarged the hole at installation (which in turn depends on your misfire percentage vs. accuracy philosophy).    Everybody's mileage may vary, of course.

[Daryl]

I used to open my WL liners to about .070", but have since left them as new, or 1/16" at the most.  They will last years for most shooters.

[chuck-ia]

Might allso want to countersink the barrel hole deep enough, so you don't end up with a thin web in the liner,  chuck

[Daryl]

Yes - that was my first mistake - the hole won't last if you have to file much off the 'flat'.

[northmn]

They last longer also if you are careful about the vent pick material you use as some picks can enlarge them over time.  Brass or the bird feathers some use are more gentle.

DP