What he said.

Pull your breech plug and ram home a sabot and bullet. There are perforations all around the sabot. There is nothing sealed about it,

Someone did some Testing with BH209 on one of the boards where they soaked a load in water. Towel,dried it and loaded it, it went bang with zero problems.

You can load BH209 and shoot it all season and leave it dirty and clean it at the end of the season, with most muzzleloading seasons lasting no more than 2 or three weeks there is NOT a better smokeless substitute muzzle loading propellant made.

Oldbob, take a piece of pipe, put pipe caps on it if you like, put it in the freezer for a day, then take it out and let it sit in a heated room for a couple of hours, take off the caps and look inside the pipe, you will see moisture. Moisture is in the air, there is air inside your barrel unless you live in a vacum. when warm temp hits cold steel, moisture is the result.

I would not leave BH209 fouling in the bore for long periods. Under the right conditions it will cause rust. Ive done it for a couple days in SS bore with no ill effects. In high humudity, no way. You are asking for a rusted bore.

Unfired, no problem. Ive left BH209 loaded for weeks on a clean bore. Never seen even the slightest amount of corrosion.

I've used BH209 in stainless Encore platform rifles since BH came out. I've fired two primers, fired to fouling shots, then loaded the rifle for up to two (2) weeks, in weather that could change from 50° and downpours, to the next day 25° and 6" of snow. Not a single time, never, notta, did I ever have a speck of rust inside any of my barrels. Taking a rifle inside and then outside can be a problem for many, especially using other propellants. Leave your case in the cold, then put the rifle in the case (after wiping down the rifle with an oiled rag), then put it into the case before taking it into the garage. The cold case will help protect the rifle and it will warm slowly. I know many shooters who foul and then leave their rifles loaded for up to two weeks, with no rust problems.

I will say this, do what you feel is right for yourself and your rifle.

Smokeless in a savagel MLII you can go as long as you can go with any center fire without cleaning.

with BH209 a couple of weeks of Hunting season is not going to have any ill effects from condensation or moisture.

I would NOT try that with any other propellant on the market, NONE!

True, oh so true.

The good thing about the pitting the Blackhorn fouling causes, is it doesn't seem to affect accuracy much.

Is it real?
 

Gm54-120,

I dunno if this simulates an actual loaded condition, or even if you can simulate such a condition. The possible compression of air within the barrel, plus the eventual compression of the powder, might flare the very edge of a sabot enough to cause a seal. This would be more possible with shallow rifling, of course. But if you did this, then removed the breech plug and powder, this might allow the sabot to "relax." Its plastic, after all. I can't think of a way to prove this.

OldBob

Another theory down the drain.
 

Oldtimr,
There's an experiment I can do! I'm about to reroute some plumbing. All I need is an end cap. I won't seal the threads. I need to do some measuring before final assembly, anyway. Might do it this weekend, I'll report back.

OldBob

Leave it in the warm air long enough for the steel to change temp. All you have to do though to prove it is take a look at an air conditioner condenser, warm air on a cold surface makes moisture, that is why your air conditioner produces water.

I shoot my MLs every day. Not because I find it necessary to keep innards dry. It's because I love to shoot my MLs.

Only thing is...... don't shoot it within a mile or two of where you park your butt in the woods. Here in northern lower Michigan, open state land is everywhere. Hardest part is finding a thick, damaged tree to shoot at. I never shoot at small, live animals or if at-all possible, hang a target on live, healthy trees.

Lastly, the nice part of having Birchwood-Casey 2 In 1 Bore Scrubber is, besides it being relatively odorless, is that it contains a small portion of rust inhibitor in it. So all that's necessary when swabbing it at camp, is 3-4 patches for cleaning and drying the barrel for the next day's hunt.

I will not trust Blackhorn 209 to keep my barrel corrosion-free either, not here in high humidity Great Lakes region...... no sirreee.