Nipple Hole Wear

[dlidster]

I'm starting a new thread because I didn't think it appropriate to hijack an existing one. Here's a quote picked up from the "Question about musket nipple hole size" thread that triggered my related thought . . .

The TC branded musket nipples that I measured (with a gauge pin set) when new had .031”/.032” diameter orifices. I find that they wear at about the same rate as #11 nipples with heavy loads - fast.

Have seen nipples open to .040” or more in 30 to 40 shots. Accuracy starts going away in my 45 shooting paper patch bullets past .038”. I toss any once they pin .036”.

For my .50 TC Hawken I have five identical TC stainless #11 nipples. One had been used quite a while, but I have no idea how many caps have been fired through it. The second, currently on my rifle, has been fired a little over 500 times. I know because I've kept track of the cap tins used. The remaining three nipples are still in their factory TC packages.

I don't have a pin gauge set to measure the holes, but I do have an old spark plug gapping tool. I have no idea how its accuracy compares with a pin gauge set, but it allows me to make an apples to apples comparison of the relative sizes of the holes in my five nipples. My measurements surprised me.

The holes in three three new nipples are a smooth "slip fit" onto the .038 diameter wire inserted from the bottom of the nipple. Both of the used nipples can almost be twisted onto the same .038 wire, but they don't "slip" on. It feels as though there's a very thin carbon coating inside the nipple. (I don't have a .037 wire on this gauge, but I believe one would fit.) Now, I'm not concerned with the accuracy of my measurements. What amazes me is there is no apparent wear on either of these nipples, one of which I know has had 500+ caps through it.

Why are my nipples lasting so much better than some reported by others here? My loads are mild, almost always 50 gr of Black MZ. All of the caps have been CCI #11 Magnum caps. I have never had a misfire or hangfire. I'll appreciate your thoughts.

 

[bang]

Probably because they are stainless.

 

[nhmoose]

Another benefit of mild loads it appears, longer nipple life. Is that with RB's?

Many conical shooters get fast nipple wear with the large charges, Parker Hales and Witworth shooters use platinum lined nipples due to that reason.

 

[mooman76]

I figure also with a larger hole, less pressure goes through it so erosion is slowed to the point of almost stopping all together.

 

[SDSmlf]

I'm starting a new thread because I didn't think it appropriate to hijack an existing one. Here's a quote picked up from the "Question about musket nipple hole size" thread that triggered my related thought . . .

For my .50 TC Hawken I have five identical TC stainless #11 nipples. One had been used quite a while, but I have no idea how many caps have been fired through it. The second, currently on my rifle, has been fired a little over 500 times. I know because I've kept track of the cap tins used. The remaining three nipples are still in their factory TC packages.

I don't have a pin gauge set to measure the holes, but I do have an old spark plug gapping tool. I have no idea how its accuracy compares with a pin gauge set, but it allows me to make an apples to apples comparison of the relative sizes of the holes in my five nipples. My measurements surprised me.

The holes in three three new nipples are a smooth "slip fit" onto the .038 diameter wire inserted from the bottom of the nipple. Both of the used nipples can almost be twisted onto the same .038 wire, but they don't "slip" on. It feels as though there's a very thin carbon coating inside the nipple. (I don't have a .037 wire on this gauge, but I believe one would fit.) Now, I'm not concerned with the accuracy of my measurements. What amazes me is there is no apparent wear on either of these nipples, one of which I know has had 500+ caps through it.

Why are my nipples lasting so much better than some reported by others here? My loads are mild, almost always 50 gr of Black MZ. All of the caps have been CCI #11 Magnum caps. I have never had a misfire or hangfire. I'll appreciate your thoughts.

My comment was about heavy loads causing fast wear. Think 400 grain plus conical in a 45 caliber gun over 100 grains of 3F Swiss. Or a 58 caliber rifle with 120 grains of 2F under a 560 grain conical.

As far as a measuring option, you can buy a welding tip cleaner set for less than $5 from most any place that sells welding equipment. While not in .001" increments, they are I believe in .002" to .004" increments and will give you an idea of the orifice size. If you are getting the accuracy you want and not experiencing hammer blowback, you are likely ok. And remember, the nipple is an inexpensive (unless platinum lined) wear item and easily replaced. More than one shooter has chased an accuracy issue all over the map only to find they had a shot out nipple. And if one day you find your hammer being in the half cock position after shooting your gun, it will only be a matter of time before you damage something in the lock.

 

[SDSmlf]

I figure also with a larger hole, less pressure goes through it so erosion is slowed to the point of almost stopping all together.

Gas flow and the particles carried by it is what erodes the orifice, not pressure. The larger the orifice, the greater the pressure drop in the bore, thus less pressure behind the bullet pushing it.

 

[Zonie]

dlidster
Just curious. Are you sure that spark plug wire guage is .038? That's a pretty weird size. .028 on the other hand is a common spark plug gap used on a lot of engines. .028 is also the common size of the hole I've seen that go thru new nipples.

Just asking but I would appreciate it if you would double check the wire size.

 

[SDSmlf]

dlidster
Just curious. Are you sure that spark plug wire guage is .038? That's a pretty weird size. .028 on the other hand is a common spark plug gap used on a lot of engines. .028 is also the common size of the hole I've seen that go thru new nipples.

Just asking but I would appreciate it if you would double check the wire size.

Most ‘new’ nipples I have checked have been between .028” and .032”, with many under .030”. Pretty confident with calibrated pin gauges I am using.

 

[Mark Herman]

Didster,
Nipples, stainless or not, used with mild and light loads will last quite a while. The heavier the load the shorter nipple life. Your accuracy will be erratic and your hammer may blow back to 1/2 cock if your nipple is worn out. Bench shooters use platinum lined nipples.

 

[dlidster]

dlidster
Just curious. Are you sure that spark plug wire guage is .038? That's a pretty weird size. .028 on the other hand is a common spark plug gap used on a lot of engines. .028 is also the common size of the hole I've seen that go thru new nipples.
Just asking but I would appreciate it if you would double check the wire size.

Yes, it is .038. I've attached the photo. Just to double-check, I measured the wire with my Brown & Sharpe micrometer that I've been using for more than 50-odd years. It's.038". These five different [genuine TC] nipples are from three different purchase periods, although I couldn't say they are from different manufacturing lots. But, they are all the same -- .038".

Hope this makes it clear. However, the point of my post was not the size of the nipple hole but my satisfaction with how well they hold up. As stated, my standard plinking and plate banging load is 50 gr Black MZ, CCI #11 Magnum primer, .012 mattress ticking patch (red-striped from Joann's), lubed with a swipe over olive oil/beeswax (5:4). and a.049 ball.

This combo loads easily and is very accurate. It appears to be easy on nipples. There's no blowing the hammer back. Spent caps are usually still on the nipple. More important, it's easy on me. I plan to stick with it.

 

[Zonie]

Thanks for taking the time to explain and to add the photo.

As for my experiance, I have never seen a new nipple with a thru hole that large.
I have seen nipples with larger holes in both ends but somewhere in the middle the thru hole was more like twenty eight thousandths.

 

[Rokon]

An associated question which I hope gets some answers is whether stainless steel or AMPCO nipples hold up better with average use??

 

[dlidster]

. . . As for my experience, I have never seen a new nipple with a thru hole that large . . .

My objective when comparing measurements among used, well-used, and new nipples was to establish how much the orifice changed over time. It never occurred to me to evaluate the actual size. Because the five nipples I'm discussing are all genuine TC parts I'm going to assume there are thousands of Hawkens, Renegades, and whatever else TC put 1/4-28 nipples in being used without problems. As I've said, mine works just as I'd expect. And I've determined they should continue to perform as I expect for quite a long time with the loads I use.

I'll continue to keep count of cap consumption and report back when I notice deterioration.

 

[Billy Boy]

My comment was about heavy loads causing fast wear. Think 400 grain plus conical in a 45 caliber gun over 100 grains of 3F Swiss. Or a 58 caliber rifle with 120 grains of 2F under a 560 grain conical.

As far as a measuring option, you can buy a welding tip cleaner set for less than $5 from most any place that sells welding equipment. While not in .001" increments, they are I believe in .002" to .004" increments and will give you an idea of the orifice size. If you are getting the accuracy you want and not experiencing hammer blowback, you are likely ok. And remember, the nipple is an inexpensive (unless platinum lined) wear item and easily replaced. More than one shooter has chased an accuracy issue all over the map only to find they had a shot out nipple. And if one day you find your hammer being in the half cock position after shooting your gun, it will only be a matter of time before you damage something in the lock.

Yes to the gas welding tip cleaner. I have a set in my shooting box. You can always find a ‘leaf’ that exactly fits the nipple you are dealing with. The tip cleaners are ringed ( almost threaded) which does a perfect job of scraping
the crust out. Also, i don't think they are overly abrasive as they are designed to clean a brass welding tip.