Ignition?

Did the cap ignite,if so most likely a clogged nipple. If not a nipplethat istoo short.

Try it again. When the 1st shot doesn't go off, re-cock and drop the hammer on it a second or third time. If it fires on the 2nd or third try, switch to Remington #10 caps. They fit the Ruger nipples better and go down flush.

Until you get some Rem. #10s, use a popsicle stick to push the #11 cap down farther down on the nipple. They have to be seated all the way.

If it won't fire at all, unclog or replace the nipple.

Pyrodex has a higher ignition temperature than "real" black powder but it should still go bang with a percussion cap. Sometimes you get a "pop-bang" effect with Pyrodex. I don't think compression alone would prevent ignition.

Did you ensure the nipples were clear and dry by popping a cap on the empty chamber? You will hear from folks who never do this, but most of us who compete with cap guns make sure the vents are open before loading. Like the others, suspect you have a bad nipple. Some Ruger factory nipples were fine, others not so much. I've got Treso nipples on all my cap guns and they ignite reliably.

there is no need to waste money popping caps in an empty chamber to ensure a clear nipple.
A needle or paper clip in the hole is fine to verify clear. or look for daylight.

Very possible you have oil contamination in that chamber,
the hard way is pull the ball dump and clean

Easier way, pull the nipple, verify it is clean and same height as the others.
Use the needle or paper clip to gently scrape some powder loose and out.
Trickle fresh powder into the hole. replace the nipple, put cylinder back in gun.
Cap and fire.

Next time before shooting. (if you have not been doing it already) thoroughly clean each chamber with a swab of rubbing alcohol ( personally after cleaning I don't lube the chambers, but then again I reload immediately).

Don't use crisco as a lube and don't use a petroleum based lube in the chambers or bores.
Personally don't know why you are using filler either. Load the gun with 25 to 30 gr and you shouldn't need to worry about seated ball height.

As others have said. Pyrodex is a bit harder to ignite than real BP, but that doesn't explain just one dead cylinder.
I've used Pyrodex P off and on for years never a ignition problem, same with real BP and T7.
I've left mine loaded as long as two year, and never failed to go bang with any powder. Except the occasional dud cap now and then.

Regarding filler, I was under the impression that for better accuracy the ball should be as close to the barrel as possible.

Click to expand...

That is often given as a good way to enhance the accuracy. But I've got a couple of 1860's that shoot groups as tight as any I can produce with any of my better modern handguns. They are simply loaded with 30 gns of powder and no filler which leaves the balls seated fairly deeply.

So the guns are already better than me by enough that any difference is hidden in my own shakiness. We're talking about sub 2 inch groups at 12 to 14 yards here to set the mark.

On the other hand an 1851 I have only takes .454 balls and shoots rather "open" patterns. I slugged the bore and it turns out that the groove diameter is significantly larger than the chamber opening. The plan is to ream out the chambers to to a thou or two larger than the groove diameter. Currently the chambers are very close to the smaller bore diameter so I feel that the issue is more than likely that the balls are not fitting and sealing well in the bore.

Which suggest that I should measure the same things on my accurate shooting 1860's to get a handle on this.... Glad you made me post this so I'd get the idea....

Anywho, the moral of this post is to consider more than one thing when determining accuracy.... and which has little to do with flashes not traveling through the nipples correctly.