Power Pro 300-MP Rant

[michaelnel]

I heard the same thing....even read it in a gun rag(don't remember which one...I think it was "Handguns"). Anytime one uses a fine powder that nearly fills the case, there will be issues with it "jumping" outta a case when using a progressive press that has movement when used.

I use a Dillon RL550B. I assure you, powder was not jumping out of the case.

 

[Ben_hutcherson]

I have loaded a fair bit of this powder, but only in one load. I use 18gr under a 158gr SWC. It's accurate and chronographs at 1500fps out of my 8 3/8" 27-2(the recoil is also "snappy" in this gun).

 

[michaelnel]

I loaded up some test rounds of this junk with 200gr Hornady XTPs and tested in my PC Stealth Hunter .44 magnum on my Ransom Rest. I loaded rounds at 27, 28, 29 grains. It almost overflows the .44 magnum case because it is so fluffy.

Worst performance by a firearm of all the testing we have done. Wild 6-10" fliers in most five shot groups. Blew unburned powder all over the bench. Lots of smoke and fire. Nasty stuff, I hope it will work well as fertilizer.

I have read so many glowing reports of this powder in .44 magnum that I have had to seriously examine our tests that day.

The symptoms we saw that day really indicated incomplete and erratic combustion of the powder. Chronographed velocities varied way more than the other powders I load the .44 with (VV N105, Alliant 2400, AA #9). Here's an example of two five round groups shot out of my 7 1/2" barrel S&W Stealth Hunter in the Ransom Rest:

Two five shot groups, 27grs, CCI300 primers, Starline brass, Speer 200gr GDHP
(FPS):
1) 1163
2) 836
3) 1149
4) 1077
5) 1122

1) 1209
2) 1162
3) 1092
4) 1188
5) 1102

Two more at 28gr, everything else the same:
1) 1199
2) 1213
3) 1008
4) 1068
5) 1109

1) 1168
2) 1133
3) 1063
4) 946
5) 1044
6) 1219

2 more groups, 29gr this time:
1) 1171
2) 1251
3) 1262
4) 1346
5) 1212

1) 1239
2) 1295
3) 1271
4) 1218
5) 1200

The 29gr grouped the best, but all had lots of unburned powder all over the bench, and the velocities are WAY low compared to Alliant's prediction for this load of 1760 FPS for 29gr.

I had used CCI300 primers. Alliant's load data showed Fed150 primers for this powder. Both are straight Large Pistol primers, not Magnums.

I am thinking that with all these symptoms I should try this stuff again but with Large Pistol Magnum primers. I have a bunch of Federal 155 Large Pistol Magnum Match primers, so I loaded some up with both 200gr XTPs and 240gr XTPs and will go shoot them today. I took the MAX loads for both as published by Alliant and reduced them by 10% to allow for the Magnum primers (I had already shot the MAX 29gr with the non-Magnum primers without issue).

I won't have access to the chronograph or Ransom Rest today, but I will be able to shoot them over sandbags and see if the unburned powder problem remains. I am betting that it will perform better with the Magnum Match primers.

 

[michaelnel]

I'm back from the range. Just as I suspected.... using the Federal 155 Magnum Large Pistol Match primers made all the difference in the world.

This is now one of the most accurate powders I have used in the .44 magnum. It shot as well as 2400 for me. No unburned powder flying out, nice small groups, lots of flash and boom. At least in MY gun, this stuff needs Magnum primers.

 

[ArchAngelCD]

Might be close to w296 and H110 but..............

Alliant data is calling for a f100 primer........
not a mag primer.

Alliant doesn't recommend magnum primers for any of their loads, at least I think they don't.

 

[EazyT]

I'm back from the range. Just as I suspected.... using the Federal 155 Magnum Large Pistol Match primers made all the difference in the world.

This is now one of the most accurate powders I have used in the .44 magnum. It shot as well as 2400 for me. No unburned powder flying out, nice small groups, lots of flash and boom. At least in MY gun, this stuff needs Magnum primers.

Just FYI Federal says their primers burn hotter and longer than other brands of primers. Also that while other companies use regular explosive compounds they use a high explosive compound and this is why they have to package them differently than other companies. Ever notice the massive plastic packaging? They say that is why that huge plastic tray is needed. So it makes sense that alliant would recommend a the hotter Federal primer for this slow burning Magnum powder.

 

[michaelnel]

WLP might work too, as Winchester designates them as being for regular or magnum loads. I do know that CCI300 sure did not get a good fire started.

 

[michaelnel]

I had emailed Alliant about my experience with this powder. Here is their response. I think he told me I'm a dummy.

"Michael,

To start with I see that you said " Do you folks have any idea why the performance was so bad (1250fps with the 200gr XTPs when your data predicts 1700+)"

When I look at the load data, I found no data using a Hornady bullet. You used data for the Speer bullet. That is like comparing apples to oranges. When you have a bullet, in this case a Hornady bullet, you need to use the Hornady load data. The bullets are made differently and behave differently when under the intense pressures that are created when fired.

In this instance the starting load for this powder and the 200 XTP bullets from the Hornady #9 manual is 25.9 and a maximum of 29.9 grains. Now, I realize that this is a similar load to that which you fired, but Hornady's published velocities are from 1300 - 1600 fps.

Hornady also used the Winchester Large Pistol Primer.

If the recipe calls for a large pistol primer then that is the primer that is to be used. Using magnum primer will increase pressures. If pressures are in excess of the cases ability, then firearm damage could result which could also lead to personal injury.

If you are not finding complete powder burn at the upper end of the load limits, try the lower limits. Start at the 25.9 grains and work up."

 

[michaelnel]

Then I read the review of Power Pro 300MP in the February 2010 issue of Handloader where the author was surprised they didn't require magnum primers.

He said he compared the stuff with LP and LPM primers and in every case the LPM outshot the LP primers. More accurate, more consistent velocities, higher velocities.

That sure parallels what I found, although it's a very small sample.

 

[tomhenry]

I know this is an old thread, but I stumbled onto it while googling load data for the 300 MP with 180 grain 44 mag bullets.

There is no load data for the 180 grain bullet and this powder. Alliant's book has 29 grains 300 MP for the 200 grain bullet. 25 grains powder for the 210 grain bullet. 22 grains powder for the 300 grain bullet.

The charges are all maximum loads.

Where would be a safe starting point for the 180 grain?

 

[johngalt]

I know this is an old thread, but I stumbled onto it while googling load data for the 300 MP with 180 grain 44 mag bullets.

There is no load data for the 180 grain bullet and this powder. Alliant's book has 29 grains 300 MP for the 200 grain bullet. 25 grains powder for the 210 grain bullet. 22 grains powder for the 300 grain bullet.

The charges are all maximum loads.

Where would be a safe starting point for the 180 grain?

What does 'no data' mean? Have you checked both the powder and bullet manufacturers?

If there is no data for that bullet, there may be a reason. Possibly it is an unsafe combinations. Or that bullet may be too light to make effective use of the powder. Or maybe they just haven't gotten to it yet.

In general, heavier bullets use less powder than light bullets. This means that you can normally use the data intended for heavy bullets with light bullets, everything else being equal (same design, lead vs jacketed, etc).

The reverse is NOT true - never use data intended for light bullets with heavy bullets. This can easily result in an overload situation.

In your case, the powder charge drops as the bullet weight increases. You can probably use the data for 200 gr bullets. As always, start low.

Disclaimer: I have never used MP-300 or .44 mag, so everything I've said may be completely wrong.

 

[tomhenry]

What does 'no data' mean? Have you checked both the powder and bullet manufacturers?

I've checked Alliant's info online and in their manual (which I have in front of me). There is no data for the 180 gr bullet. Actually, the data which they have listed is only for maximum charges. They don't list any safe beginning charge. Alliant is notorious for too little information.

And I've checked Hornady's website. They say to check ballistics data on their online store link, but I can't find their "online store" link. ???

that bullet may be too light to make effective use of the powder.

That's curious, because Alliant's reloading manual gives powder charges for 300MP for 125 grain 357 bullets. If it's suitable for the 125 grain bullet, I can't see where there would be a problem with the 180 grain bullet.

 

[Domino300]

received info for for MP-300 from Alliant a year ago for 41 Mag:


Amonette, Ben([email protected])


3/26/13

To: xxx

We have not tested 300MP in this application but you might start with 21 grs and the max should be approx. 23 grs. Be sure and start with the minimum charge regardless of which primer you choose. A firm crimp on the bullet is recommended. Thanks for your note.

I settled on 22.5 gns.,WLP, with Sierra 210JHC and avg. 1394 fps. I remember a wide variation in the fps though.

 

[aurora40]

I've checked Alliant's info online and in their manual (which I have in front of me). There is no data for the 180 gr bullet. Actually, the data which they have listed is only for maximum charges. They don't list any safe beginning charge. Alliant is notorious for too little information.

And I've checked Hornady's website. They say to check ballistics data on their online store link, but I can't find their "online store" link. ???

You have to buy the book to get Hornady's data. Just FYI, they don't have any 180gr .44 Mag data for 300-MP either in the 9th edition. They actually don't list any for H110/W296, AA#9, or other slow powders for the 180gr XTP. Perhaps the lighter bullets don't hold together well at higher velocities?

In the bullets data section, they list a range of 750-1400 fps for the 180 gr XTP, whereas the 200 gr is "ok" up to 1650fps, and the heavier bullets are good up to 2200.

I get what you mean about Alliant's data. But they do say to start 10% under the listed. And it is free. Hornady has fewer combos tested with 300-MP, and it isn't free. Though they do list a range of loads for the bullets they did test. But there's no pressure info or anything either.

 

[Jaymo]

The Vihtavuori load manual from the mid 1990s listed 27.1 grains of N110 and a 180 grain XTP doing 1816 fps from a 7" barrel.
I can tell you from experience that the bullets don't hold up great at that velocity.
A few years later, they increased the max load to 27.5 grains of N110 with the 180 XTP.
Now, they've dialed it back a bunch.
I don't know why, the pressure listed at 27.1 grains was about 3,000 psi below max pressure for .44 mag.

I'm thinking 300 MP is capable of the same level of performance, but there's not much point in driving a 180 grain XTP that fast.

 

[sw282]

Old thread, but new to me... Found 2 boxes of 158gr XTPs in my stash.

My Hornady #9 says Power Pro 300MP will make them fly 200fps FASTER.

''A bunch more than the next powder flavor listed''

Just looking for the BEST and Fastest ''SAFE'' load for my 686 Competitor.

Got some 55 pound steel Rams l need to K I L L @200 Meters...

thanks

282

 

[aurora40]

My Hornady #9 says Power Pro 300MP will make them fly 200fps FASTER.

''A bunch more than the next powder flavor listed''

I think part of the reason for that is that they used an 8" barrel. For me, with a 4" 357, I was only ever able to get 1220 FPS with a max load of 300MP and a 158gr bullet (using Alliant data and components, which was about a full grain higher than the Hornady data). This is not overly impressive, and factory ammo like American Eagle exceeds it in my firearm. However, it really came alive in a 16" carbine, going almost 1900 FPS.

I think the longer the barrel, the more likely it will exceed other magnum powders.

 

[muddocktor]

I've also found that 300MP also likes a closed chamber better than an open chamber such as a revolver also. I had loaded some in 357 Mag and also in 44 Mag. I don't remember the data, but do remember they weren't very far off from max load data from the Hornady #9 manual. In my 5" 27-2, they were some of the dirtiest rounds I've shot in that pistol and they didn't feel especially powerful. But out of my 20" barrel Rossi 92 SRC they kicked some serious butt. And in 44 Mag, I didn't own a revolver at the time; just a Desert Eagle. And in the DE they were some potent rounds and a real hoot to shoot with big recoil and flash. And in my 20" barrel Browning B-92, they would kill on both ends. They were accurate but recoil in that gun would eat your shoulder up and after around 20 rounds they were not fun at all.

 

[g17]

Recently, I've been playing around with 300MP and hope to do so more testing next week. I've favor 2400 for my magnum loads but 300MP seems promising so far. It's very fine but meters well from my chargemaster and it burns clean enough. From a 4" GP100 using Alliant data and S&B primers, I averaged 1324fps/615.10ft-lbs with Nosler 158gr jhp and 1560fps/675.58ft-lbs with Everglades 125gr jhp. I wasn't able to shoot under the best conditions so will be clocking this some more using different barrel lengths to see how it works out.

 

[Dave Workman]

I have come into a pound of this stuff. I intend to try it in my .41 Magnums, but loading data is almost non-existent, and this propellant has been around long enough that YOU WOULD THINK(!) that somebody at Alliant / Speer / Sierra etc would have by now come up with some loading data.
Geez, Louise!
I found one — COUNT 'EM, 1 — load for a 125-grain JHP for .357 Mag, and it frankly seems a bit hot for a .357 Magnum.
The burn rate is about the same as H110 and 296, according to a chart in Nosler #8.