Actually all powders make a crud ring of sorts. They are just in different places and different degrees of hardness. All a crud ring is basically is the fowling produced by the ignition of the powder. Sometimes, like in the case of Triple Seven in some rifles, this fowling is very hard in nature and feels like a bump. For a better way of explaining it. A moist patch will scrub that right off when swabbing. So if you swab you very well might not ever feel a crud ring.

In the case of Pyrodex RS or P there is a crud ring. Its just spread out. Swab the bore and you will see the crud. It just does not ring up per say. The fowling is normally softer in nature too. BUT when you swab the bore you are technically taking out the crud ring in the form of fowling. You know, all that black junk on the patch.

APP and others like that.. ever see the white ring near the muzzle of the rifle. And feel that white ring. That is unburnt powder sticking to the barrel. Just in a different place in the bore and different consistency.

BlackHorn 209 might be a powder without a true crud ring of sort. BUT there is a black fowling in the bore. And with Black Horn it takes solvent to remove that, not a simple swab solution. Although alcohol will take it out if you want to swab between shot. Also if you say crud ring.. hows your breech plug? When I shot that powder the accumulation of hard to remove crud in the breech plug made cleaning that rifle just about as time consuming as with other powders. I swear that breech plug took me about ten minutes to get it to MY standards.

Now I am fussy. And when in no hurry have been know to take a half an hour per rifle when I clean them. But when I am done, you can rest assured there is no sign of fowling, crud ring, or anything. Just a smooth mirror like bore, well protected with a quality oil product.