H-110 or 300-MP

There is a

AJC1 said:

So I am wondering if 300-mp is just alliant's version of H-110 or if there are any major differences. Any one do back to back testing. I hear 300-MP has some claims of speed that are not exactly true....

Click to expand...

Here is a thread that might give you some answers.
https://www.thehighroad.org/index.php?threads/power-pro-300-mp-anyone.852662/
Post #10 by forrest r.

I've done a little head to head testing with 2400 vs h110 vs mp-300 using different firearms bbl lengths with the 357mag & (44mag/very little/4"bbl only).

When you started getting into 6" or longer bbl.'s the h110 & mp-300 started to shine. The mp-300 pretty much mirrored the h110 velocity wise & the velocities listed by allaint for their mp-300 was within 20fps of what I was getting with a 10" bbl'd contender.

Haven't burned thru a lot of mp-300, just about done with the 3rd pound I bought. I will be buying/using more in the future. I'm really interested in doing testing with different cast/coated bullets in 44mag contender bbl.'s.

I have not yet used H110.

My experience with 300-MP is that, more than with other powders, it works better in longer barrels and with heavy for caliber bullets.

An example of this would be that I get just under 1200fps from a .357 mag 158gr JHP out of a 4.2" barrel. I also get just under 1200fps from a .44 mag 300gr JHP out if a 4.625" barrel.

I've yet to do much testing with longer barrel, except a lever action in .357. But it seems to me that 300-MP is a very good choice for hunting revolvers, and not so great for much else.

I’ve been playing with 300MP for subsonic heavyweight 300 Blackout loads. My impression is that it’s a bit slower burning than H110. In this particular application it’s fairly dirty and I get a lot of gas and particle blowback when shooting suppressed. I agree that it’s better suited for heavy magnum pistol loads.

AJC1 said:

I would be most interested in any feedback you have from the lever gun as that would be my intended purpose

Click to expand...

I'd have to check my data book when I get home, but I did chronograph the load, which was with a 158gr Speer Gold Dot/Deep Curl. I think I was maybe 0.1gr below Alliant's listed charge. And it wasn't as fast as I was expecting. I think around 1750fps from a 20" barrel.

I know someone else on THR was running max charge with a 158gr XTP from a rifle, and getting slightly higher velocities. I'm not sure if H110 would have an edge in such a barrel. But perhaps other have some data for H110/W296 in a rifle that they could look up for you.

It sure would be nice if QuickLoad had 300MP in its database.... <sigh>

My experience with 300-MP is that it doesn’t start to show any benefit over other powders until you go over ~8” barrel length. In the longer barrels, it gives more velocity with less pressure than H-110. It also doesn’t require magnum primers.

I like it for my 357 and 44 magnum loads in my rifles. I get 1800fps with 158 XTP bullets in my 16” Rossi.

Toprudder said:

My experience with 300-MP is that it doesn’t start to show any benefit over other powders until you go over ~8” barrel length. In the longer barrels, it gives more velocity with less pressure than H-110. It also doesn’t require magnum primers.

I like it for my 357 and 44 magnum loads in my rifles. I get 1800fps with 158 XTP bullets in my 16” Rossi.

Click to expand...

I was hoping you'd swing by at some point.

I still find it amazing that you get 1800fps from a 16" barrel with a 158gr JHP, whilst I get less from a longer pipe. I can't see that difference coming from 0.1gr of powder, or the XTP vs Gold Dot. I wonder if my load is just out of powder to burn and slowing down in a 20" barrel.

I should try so max charge XTPs and see what I get.

And here's the data I have from my 20" lever action (Henry).

Speer 158gr Deep Curl
CCI 500
Starline brass
18.5gr of 300-MP (Alliant max is 18.6gr)

10 shots
Hi - 1801
Low - 1696
Ave - 1759
E.S. - 105
S.D. - 36

The High was the only one to hit 1800, the Low the only shot below 1700. It happened to be sunny and 95 degrees on the day. I don't know how the temperature effects 300-MP but I did some other testing before I got to the rifle. So the ammo may have been quite warm. It could also be the charge isn't quite high enough (though it pretty much at max).

Toprudder said:

My experience with 300-MP is that it doesn’t start to show any benefit over other powders until you go over ~8” barrel length."

Click to expand...

My experience with a 7.5" SBH is consistent with this. With 240 gr JSPs I saw only ~30 fps more with 300-MP over H110.

In a 20" Marlin 1894 I saw ~170 fps increase with the same 240gr JSP and 300MP over H110.

ETA: I'd expect that the heavier bullets would show more separation in velocity as someone posted above.

WrongHanded said:

I was hoping you'd swing by at some point.

I still find it amazing that you get 1800fps from a 16" barrel with a 158gr JHP, whilst I get less from a longer pipe. I can't see that difference coming from 0.1gr of powder, or the XTP vs Gold Dot. I wonder if my load is just out of powder to burn and slowing down in a 20" barrel.

I should try so max charge XTPs and see what I get.

Click to expand...

Went back to look at my data:

Hornady 158FP/XTP bullets, 300-MP, CCI 500, Rossi 16”
17.3gn, 1729fps, 14.0sd
17.6gn, 1758fps, 15.9sd
17.9gn, 1760fps, 16.3sd
18.2gn, 1800fps, 16.5sd
18.5gn, 1828fps, 33.5sd

It is interesting to note that I saw a velocity increase all the way up to max charge in the 16” rifle. With a 5” revolver, there was no velocity increase at all with the last 1.6 gn increase in charge. Zero. The max velocity from the 5” revolver was ~1200fps.

Toprudder said:

Went back to look at my data:

Hornady 158FP/XTP bullets, 300-MP, CCI 500, Rossi 16”
17.3gn, 1729fps, 14.0sd
17.6gn, 1758fps, 15.9sd
17.9gn, 1760fps, 16.3sd
18.2gn, 1800fps, 16.5sd
18.5gn, 1828fps, 33.5sd

It is interesting to note that I saw a velocity increase all the way up to max charge in the 16” rifle. With a 5” revolver, there was no velocity increase at all with the last 1.6 gn increase in charge. Zero. The max velocity from the 5” revolver was ~1200fps.

Click to expand...

It looks increasingly likely that at a certain point between 16" and 20" of barrel, velocity starts to drop off.

And it's curious that you get around 1200fps from a 5" barrel. I got 1190fps from a 4.2" barrel with a max charge. But I suspect, this powder could push a 180gr bullet to th same velocities in those guns without going over SAAMI MAP pressure. I may have to try this.

2400 does the same thing, it's called diminished return.

Bullet selection plays a huge role in the velocity results of your mp-300 reloads, as does the crimp.

FWIW:
I used these bullets to do head to head testing with 2400 vs h110 vs mp-300. Didn't matter if I used the 158gr hp or the 170gr fp. The results were the same.


2 1/2" bbl ='s 1200fps with 2400, the h110 & mp-300 were in the 1150fps range. The bbl was just too short. (revolver)
4" bbl's ='s 1310fps with h110/mp-300 (2 revolvers)
6" bbl.'s ='s 1456fps with h110/mp-300 (3 revolvers)
8" bbl ='s 1507fps with h110/mp-300 (revolver)
10" contender bbl ='s 1632fps

forrest r said:

FWIW:
I used these bullets to do head to head testing with 2400 vs h110 vs mp-300. Didn't matter if I used the 158gr hp or the 170gr fp. The results were the same.

Click to expand...

Just to clarify, are you saying bullet weight did not effect velocity?

WrongHanded said:

Just to clarify, are you saying bullet weight did not effect velocity?

Click to expand...

Yes that's exactly what I'm saying.

I have a 4-cavity mold that has cramer style pins in it & the mold casts large round hp's, penta point hp's or solid nosed fn's. Same mold/bullet/lead alloy/ect. The difference in bullet weight between the 158gr hp and the 170gr fn is 7.5%.

I get the same velocity with either bullet. Keep in mind that both bullets have the same shape, same bearing surface, drive bands & seating depths.

This is 1 of the huge advantages of having bullet molds with multiple cavities and several different hp pins along with pins to cast solid nosed bullets in the same mold. I do the same thing with these 44cal hp's, same powder charge/weight, different hp for different applications.

I've tried the 300 MP in 22 Hornet and it does a bit better than H-110 with 50gr bullets in a 1:9 22" barrel.