More Black MZ testing

[rsrocket1]

Got out for some more Black MZ testing today at the range.

Observations so far:

You really need to weigh the powder out. You can get > 10% variation if you try to measure by volume.
You need to crunch down the bullet and compress the powder
A crusty built up occurs at the breech. I don't have "cold" muzzleloader primers, only W209, CCI209M and Fed 209A available and don't want to spend 2x or 3x for weak primers so I don't know if that will eliminate the crusties. The crust cleans off with a single dry patch.
Black MZ produces as much smoke as black powder, but it doesn't stink. It simply smells like lots of smokless power smoke.
Cleaup is very easy with a couple of wet patches of Hoppes #9 followed by a couple of dry patches


Here is my latest shot string:
Date 12/1/2013 Temp 64F
Bullet: Lee TL452-230-TC in T/C yellow sabot, CCI209M Primer,
Powder: BlackMZ 88.0g by weight (100g volume BP equivalent)
1 1858
2 1908
3 1850
4 1852
5 1846
6 1873
7 1860
8 1849
9 1857
10 1845

Min 1845
Max 1908
Ave 1859.8
Ex Sprd 63
Std Dev 18.8

Things I changed since the last session that may have helped consistency in MV:
Ran both sides of a dry patch between each shot. Here are a couple of picture of the "crusties":
9141991420

At first, I thought they looked like white versions of the powder, but on closer inspection, they look like crystals. Maybe it's a by product of the citric based powder. Anyway, they stick to the breech area pretty firmly and if you don't have a good grip on your range rod, the patch could get stuck down there. You can reduce the chances of a stuck patch by working the patch up and down a few inches at a time toward the breech. After flipping the patch and running it down, the breech is clean and shiny.

I bought a 3/8" x 48" Aluminum rod at the hardware store yesterday as a range rod. My first attempt using 3/8" Delrin was OK, but there is a lot of flex to the rod and you need to push the bullet down in 3-4 steps, otherwise the rod flexes too much. I used the Aluminum rod to "pre-crunch" the powder. The powder compresses anywhere from 1/4" to 3/8" (maybe more) with the bare rod against the powder. That's a lot and it would be tough to get a consistent crunch with a tight fitting sabot.

The groups were not great with about a 2" horizontal spread and lots of vertical stringing because I was probably reloading and shooting too fast (maybe 2-3 minutes between shots). I could tell because the barrel was pretty warm by the last few rounds. Using a 45ACP cast boolit is also probably not a good 100 yard load. I start out with near single hole groups at 25 yards that spread out to 4"+ at 100. The T/C .451 to 50 cal yellow Super Glide sabots open up quickly and most fell 25-35 yards down range. In fact the sabots open up so quickly that I broke 2 skyscreen rods from the sabots. Fortunately, I make them out of wooden dowels so they don't break the plastic housing when I shoot them. The chrony actually kept reading the speeds reliably so I didn't even need them today.

I took a picture of the "scorched" breech plug face when I brought the gun home for clean up:
89230
It cleans up very easily with Hoppes #9 and very gentle rubbing with a section of Scotch Brite pad. You could also use a brass brush, bronze wool or other soft metal like the edge of a penny to scrape it off. Be sure to use a 7/64" drill bit mounted on a drill to clean out the flash channel down to the point that it gets small. Don't turn the drill on, just mount the bit, insert the breech plug and twist the breech plug. The flash channel had lots of soft soot with 20 shots through it.

Conclusions from today:

With weighed charges and a consistent seating procedure, you can get fairly consistent velocities with Black MZ.
If you have an easy fitting bullet, you might be able to crunch down hard while seating the bullet. Otherwise, a "pre-crunch" with a stiff bare rod will also work.
Cleaning the barrel and especially the breech is not necessary to keep shooting, but it helps a lot in getting consistent velocities.
Ignition was never an issue, all shots fired perfectly and instantly without the need to clean the breechplug while at the range but:
Cleaning the breechplug especially the flash channel is very important because there is a lot of soft crud in there.

[johnson1942]

the spread between ft. per sec is getting more narrow. will be looking foreward to what they are with heavier paperpatched bullets.

[GunSlingerNM]

I shoot Black-MZ in my revolvers and really compress the snot out of it. Tight groups. Will try and borrow a chrono and let ya know how fast it flies.

[marquette]

In my 1:20 twist barrel using MZ I found that a larger bullet with thinner sabot shoots tighter groups at 100yd than a smaller bullet with thicker sabot. A .451 PT Gold 260 gr bullet shoots better than a Hornady .430 XTP. It could be the ballistic tip because but I didn't do well with .451 hollow points either. I can short start the bullet/sabot and then run the bullet down onto the powder with one long motion. Then I compress the powder with a steady pressure until i feel the recoil pad begin to give. not very scientific but it's the best I can think of for constant pressure.
Try contacting Ron Bugg at Harvester Muzzleloading, tell him what you are doing and ask for some samples of bullets and sabots for testing. They are very good at offering them to help shooters find the right combination.
If you do a internet search for Toby Bridges North American Muzzleloading you will find several good articles on various powders, sabots, bullets and their ballistic properties. He helped me a lot last year understanding the proper load for a 1:20 barrel vs 1:28 or 1:32.

[carbine]

What do the groups look like?

[marquette]

I just realized that you said Hoppes #9 fr cleaning and show the bottom of a bottle in your picture. Black Mz is water soluble . Alliant recommends a water based cleaner to clean the barrel and breech plug. That may explain some of the crusties.