BlackMZ Load Data .45-70

[David Greene]

I have read many folks questions about BlackMZ, searching for feedback and advice for cartridge load data. I was fortunate enough to purchase 5 pounds from Shooters Warehouse for the bargain price of 9.99 a lb. I made this purchase about the same time I picked up a Pedersoli Q Sharps Rifle in .45-70. My hope is to compete in the next year or so at the Quigley Shoot in Forsythe, Montana. I began working up loads and I would appreciate any lessons learned you folks would like to share.

Thanks!
Dave

 

[Don McDowell]

I've yet to see a rifle that would shoot the subs to the level of accuracy of real black.
You may want to do a chamber cast on that rifle and see which throat they have in the gun, and what dimension of the bore and the grooves are. Generally a pedersoli 45-70 pedersoli does it's best work with a 530ish gr bullet at .460 diameter, cast from 20-1 or harder.
The Quigley is something anybody shooting bpcr should do once, it's a huge crowd. So be prepared to spend 2-3 hours waiting for your squads turn to get up on the line and shoot your 8 shots in about 15 minutes. Sign up to shoot the yellow targets, and hope you get to shoot the buffalo target first thing in the morning when the breeze is calm. Most years if you miss more than 8 shots you'll be well out of the running for any of the high prizes.
Have fun.

 

[Dog Soldier]

I use black powder in my B/P firearms. But I am not familiar with the BlackMZ? Anyone used it to share their experience, educate me?

 

[Don McDowell]

BlackMZ is relatively new to the market. I have not messed with it, as the NRA changed the rules from allowing any substitute back to Pyrodex being the only allowable substitute powder. After reading the information on the stuff I would imagine it's like the other sugar based subs, don't use a water based cleaner or it will pit the barrels, and the cases will still need to be cleaned or the residue will eat them. BH209 delivers good accuracy, and will rival the accuracy of black, but the pressures are pretty high and resizing after each firing is necessary to get a good neck tension on the bullet, and easy chambering.

 

[David Greene]

Ok.. Just returned from the range with some BlackMZ performance data to report.
Duration of Firing: 1hr 20 min
Weather:
Temp at time of firing:39 to 41 degrees fahrenheit.
Barometric Pressure: 29.82 in
Humidity: 54%

Cartridge: .45-70
Primer: CCI 250 Large Magnum Rifle Primer
Propellant: Black MZ- Charge Weight 55.0gr with Over Powder lubricated wad "Bridgers Best"
Projectile: 500grain RNFB Hard Cast Penn Bullet URL-http://www.pennbullets.com/4570/4570-caliber.html
Brinell Hardeness: 20
Lubricant: Coated in Dupont Dry Teflon- Lube Grooves filled with Kiwi Beeswax/Lanolin
Compression: Heavy
Seating: .015" of top band exposed (slightly high but not fully engaging rifling)
Crimp: Factory Crimp- Lee "Tight"

Weapon: Perdersoli Q Sharps 34" Octagonal Heavy Barrel.
Firing consisted of 2 five round groups. No swabbing between shots, bore evacuated between shots with exhaled breath.
Velocity measured fps with Caldwell BPC placed 5 meters forward of muzzle.

Group 1
1- 1253
2- 1266
3- 1277
4- 1240
5- 1287

Group 2
1- 1259
2- 1260
3- 1272
4- 1263
5- 1269

Note: If tomorrows weather conditions are similar I intend to repeat the firing. Setting down today to create 10 matching test cartridges.
Comments? Suggestions?

All the best,
Dave

 

[Don McDowell]

I'ld loose the crimp, and leave the lube off of the over powder wad.

 

[Dog Soldier]

I use black powder. I was not aware of the bore damage done by the sub propellants. Thanks that is very important information.

 

[David Greene]

I'ld loose the crimp, and leave the lube off of the over powder wad.

Don,
Thank you for the suggestion. I will implement that once I confirm there is no great variance between my first two strings and the second two. Then we can see what changes in velocity the change makes.
My game plan is to get a consistent velocity with a dependable load. Then I will move on to bench rest tests for accuracy using a 50 and 100 yard target array.

Many thanks!
Dave

 

[Don McDowell]

It's looking like that barrel needs to be warmed up good before things start to settle down. That could change in warmer weather.
I would take a close look at 10 shot strings to really determine if you've got a good load or not. If the gun starts to get fouled out, you'll get a ton of vertical stringing.
You may want to think about just running a dry patch down the bore between shots, or a patch just damp with a solvent of some sort. For serious target work I use a 2 1/2 inch flannel patch dampened with Napa cutting oil and water mix at 1 part oil to 7 water.

 

[David Greene]

It's looking like that barrel needs to be warmed up good before things start to settle down. That could change in warmer weather.
I would take a close look at 10 shot strings to really determine if you've got a good load or not. If the gun starts to get fouled out, you'll get a ton of vertical stringing.
You may want to think about just running a dry patch down the bore between shots, or a patch just damp with a solvent of some sort. For serious target work I use a 2 1/2 inch flannel patch dampened with Napa cutting oil and water mix at 1 part oil to 7 water.

Roger that. 10 Shot strings it is. I will report results as soon as I get back to the range.

Thank you Sir!

 

[Don McDowell]

hold hard and squeeze center.

 

[alsaqr]

"After reading the information on the stuff I would imagine it's like the other sugar based subs, don't use a water based cleaner or it will pit the barrels, and the cases will still need to be cleaned or the residue will eat them."

I've used Black MZ since it first hit the market. Black MZ is not sugar based, it is ascorbic acid based.

 

[daboyleroy]

Check it out at
http://www.chuckhawks.com/blackMZ.htm
Black MZ was introduced at the 2011 National Association of Sporting Goods Wholesalers (NASGW) in Reno, Nevada in November 2011. As such, it was a bit late for most folks to consider hunting with it during the 2011 seasons. We received our supply of Black MZ shortly after the 2012 SHOT Show in Reno, Nevada and began testing as soon as we returned home.

Most everyone who has read our articles knows that we have been pellet shooters for years. I think that is one reason the folks at Alliant wanted us to test out their powder. They wanted us to explore another option for hunting here in the west.

Black MZ is a citric-based powder, as such; it is less hydroscopic and should be cleaner burning and less corrosive than most other black powder substitutes. With that in mind, we ran tests during our dry season with the humidity at 10% and during our monsoon season when the humidity reaches above 80%. We experienced no difference in ignition and cleanup was easy under all conditions.

 

[David Greene]

Just returned from the range with NEW BlackMZ performance data to report.
Duration of Firing: 2hr 10 min
Weather:
Temp at time of firing: 29 to 31 degrees fahrenheit.
Barometric Pressure: 30.01 in
Humidity: 49%

Cartridge: .45-70
Primer: CCI 250 Large Magnum Rifle Primer
Propellant: Black MZ- Charge Weight 55.0gr with Over Powder lubricated wad "Bridgers Best"
Projectile: 500grain RNFB Hard Cast Penn Bullet URL-http://www.pennbullets.com/4570/4570-caliber.html
Brinell Hardeness: 20
Lubricant: Coated in Dupont Dry Teflon- Lube Grooves filled with Kiwi Beeswax/Lanolin
Compression: Heavy
Seating: .015" of top band exposed (slightly high but not fully engaging rifling)
Crimp: Factory Crimp- Lee "Tight"

Weapon: Perdersoli Q Sharps 34" Octagonal Heavy Barrel.
Firing consisted of 2 five round groups. No swabbing between shots, bore evacuated between shots with exhaled breath.
Velocity measured fps with Caldwell BPC placed 5 meters forward of muzzle.

I warmed the barrel up by firing 10 rounds of older BlackMz loads 55 grains under a 350gr bullet with CCI 250 LMRP.
The barrel was cold soaked and close to ambient temperature. Results as follows:
1- 1573
2- 1607
3- 1569
4- 1581
5- 1513
6- 1533
7- 1584
8- 1610
9- 1691
10- 1620

The barrel was warm to touch. I swabbed with wet patches soaked in Hoppes. Dry swabbed till clean.

For record shots were 55gr under a 500gr RNFB with Bridgers Wads and heavy compression by no crimp as Don McDowell suggested.
Results:

1- 1227
2- 1219
3- 1173
4- 1266
5- 1213
6- 1235
7- 1203
8- 1263
9- 1189
10- 1222

AVG= 1220.70
AVG DEV= 21.3
STD DEV= 28.8

I am satisfied that this particular load using BlackMZ demonstrates consistent performance. The next question is how accurate is the load as measured by the groups fired.

I am headed back tomorrow to assess 50 and 100 yard accuracy at this load level. More as I learn it...But I really like BlackMZ.

 

[Jim Watson]

That will be interesting.

Note that a respectable load with black would have single digit standard deviation. A GOOD load with black would have single digit extreme spread.
Uniform velocity is important with BPCR long barrel time and long time of flight.

 

[Don McDowell]

Can you shoot further than 100 yds? 2 and 300 will tell you more about the accuracy your getting. Keep in mind at the Quigley the closest target you're going to shoot will be the bucket, shot offhand at 350. The next step would be to put the gun on paper at 800, once you get past 500 yds you'll soon know if the bullet you're shooting will be stable or not.
The velocity you're getting is comparable to a good 2f bp load, with the exception as Jim noted of the velocity spread. That spread will be enough to cause some real problems with vertical stringing past 300.

 

[David Greene]

Don, sorry it took so long to get back and respond. Thank you for your advice. It is spot on. My best chance for a 1,000 meter range is to go down to Quantico. The Marine Base shares its facilities with the Quantico Shooting Club. II will have to plan carefully to get on the 1,000 meter range but I should be able to sometime this spring. The Quigley allows for all types of powder. I am going to work up BlackHorn209 loads next. The purport to have std dev or 5 with 500 grain round nose riding on 32.9 grains. If that doesn't improve on BlackMZ then I will try Varget.

 

[Don McDowell]

David they have a BPTR match at Quantico every year. Also there is one held at Reade Pa.
Also keep in mind you can shoot the bpcr silhouette matches, but your powder will keep you from qualifying for awards.
Have fun with it and keep us posted

 

[David Greene]

Hey Folks,
Its been a while since I was last on. Since we last chatted I have worked up BlackHorn209 and VARGET loads for the .45-70. I will be shooting this weekend and will pass on string data for 350gr, 405gr, and 500gr RN on both propellants. ALERT- BlackMZ is back at Sportsman's Warehouse for the bargain price of 9.99 a lb. I just bought 10lbs. I know this product isnt quite up to Holy Black Standards...but I urge yall to give it a try. At 9.99 a lb you can't go wrong. Happy trails to all my friends. More after this weekend shoot.

All the best,
Dave

 

[Don McDowell]

The thing with this powder is , it isn't legal in any of the matches I shoot, only real black or pyrodex is allowed, so while it might be cheaper, and it may work good it serves me no purpose.
But I am interested to see how it works.

 

[RPRNY]

I am prejudiced and only shoot actual black powder, so I will not opine on Black MZ.

I suppose magnum rifle primers are recommended with this substitute? With black powder I would have suggested trying your load with large pistol primers which suits real BP well.

As per above, I would loose the Lee crimp. A light taper crimp that takes the bell out of the case mouth should be just enough. As little disruption to the bullet base as possible is ideal.

BP wants pure lead. Again, as I am not knowledgeable about Black MZ, if using hard cast is some kind of requirement, then please disregard. At those velocities, BHN 8 is as hard as you want and for best obturation, I would prefer pure lead.

While the advice above on standard deviation and extreme spread is more stringent than my own views, they are directionally correct. Given the temp at time group recorded, I imagine extreme spread and standard deviation have closed up with warmer weather?

 

[Don McDowell]

Many of us shooting bptr and bpcr competition are using alloys of 16-1 and harder, one of the guys that name appears on the Castle Trophy even uses a bit of antimony in his alloy.

 

[David Greene]

RPRNY, I am hoping that with warmer weather spreads should reduce. Don warned me about that early on. My hope is to build a respectable body of meta data sufficient to derive 95% probability at the 95% confidence level (which is starting point we use in military testing of weapons. This means a lot of shooting which of course suits me right down to the ground.

 

[alsaqr]

BlackMZ is relatively new to the market. I have not messed with it, as the NRA changed the rules from allowing any substitute back to Pyrodex being the only allowable substitute powder. After reading the information on the stuff I would imagine it's like the other sugar based subs, don't use a water based cleaner or it will pit the barrels, and the cases will still need to be cleaned or the residue will eat them. BH209 delivers good accuracy, and will rival the accuracy of black, but the pressures are pretty high and resizing after each firing is necessary to get a good neck tension on the bullet, and easy chambering.

Been using Black MZ powder since it first hit the market. Black MZ is not "sugar based". The Black MZ base is ascorbic acid. Using water to clean the bore will not cause pitting.

 

[hepburn45-70]

Dave, did you ever make it to the Quigley shoot?