4000-MR experiences?

[upacreek]

I have been playing with 4000-MR lately in my .243 and 7WSM. After trying several other powders my best accuracy has been with this powder. I wanted to use Rotumbo in my 7WSM, but since I havent seen any on the shelf for a long time im hoarding it for another gun. I tried Magpro, 7282SSC, and H4831. The 4000-MR has proven most accurate and highest speed in an accuracy window. Mostly this is in my 7WSM since I just had a new barrel installed. My .243 has showed great results also.
So after getting all excited about my new find I decided to research a little about it. I've read every post on this site and it sounds a little discouraging. I plan on doing a temp test in the next week or two.
What are your experiences?

 

[AZShooter]

I jumped on it when it first came out in 2013. I read on Accurate shooter site that it was a slower longer burning curve powder like RL-17. I did some comparisons of it and RL-17 for accuracy and velocity.

From my documents files when I first wrote about it:

My biggest disappointment is that this new Power Pro 4000 MR was presented as another long burning curve powder similar to RL-17. 6mmBR said something to that effect last September AND I called and talked to a representative from Alliant, who also said it was similar to RL-17. I don't believe it has the same formulation as RL-17 or it would have beaten it in some of my tests.

To its credit it seems to have some nodes that were accurate with minimal velocity differences. I will be shooting one accurate load in a 7 rem mag soon to see just how consistent it is. While velocities were down compared to other powders it might be a good one for tight groups. FYI I have not heard from the Alliant Rep I e-mailed. I wanted to know if it was an extreme powder. RL-17's canister says it is, 4000 MR makes no mention of it.

Impressions: this powder didn't surpass RL-17's velocities in the short barrel but duplicated and slightly surpassed RL-17 in the longer barrel. Some velocities were very similar. Has accuracy potential.


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While discussing it with others one guy posted:

I recieved an e-mail from alliant about the temp. sensitivity of 4000 MR, They are calling it moderatly temp. sensitive...

I used up the powder I had on a 243 and 30-06 and never purchased any more.

 

[upacreek]

I did a little testing. I found a load near max but appeared safe. I froze 3 rounds at 0 deg. I set 3 other rounds under my wood stove for 36 hours and measured temps several times. The rounds measured 109-113 deg over 36 hours. At the time of shooting 110 degrees was measured.

7WSM
162 ELD-X (.010 from lands)
66gr 4000-mr
New unfired winchester brass
CCI250 primers

Cold
3130 fps
3146 fps
3187 fps (3.25" group at 400yrds

Hot
3245 fps
3234 fps
3227 fps (5.5" group at 400yrds)

I am gonna give up on this powder. I have liked it in my .243, but realize now I never shoot that gun under 80 deg. I pulled out the gun today and stuck 3 bullets in the freezer for 45 minutes. Totally missed the target. No hits on paper. I stuck 3 under my stove at the same time the others were in the freezer. Those 3 shot a 2.75" group 2" high and 2.5" right. My .243 is sighted in for 300yrds so my dope might be off.

 

[upacreek]

I have some rounds loaded with magpro. Does anyone have anything good to say about magpro?

 

[jjmp]

Thks for the above info, played with Magpro in a 1885 Winchester 270/wsm ,28 inch octagon bbl ,speeds were impressive & accuracy fine ,bullets loaded were Speer 130 bts & Barnes 130 triple shocks ,brass w-w ,primer cci250 Or f215"s the Speers took 3 lopes out west plus a coyote ,then took 2 does & a nice buck in wis . It's made for the wsm family but I'd not shoot them in 80 degree weather ,with out reducing the powder charge , never shot them in cold weather like below Zero but I'd still Cronograph them then and Simply adjust scope and hunt !

 

[venatic]

I have used 4000 MR in a variety of rounds from 6.5 Creedmoor to 300 WM and also did some temp testing and found what Alliant said to be true..... it's not as good as some but not nearly as bad as others so moderately temp sensitive is a good description.
I know do one custom ammo maker who uses it extensively with very good results.

 

[upacreek]

I have used 4000 MR in a variety of rounds from 6.5 Creedmoor to 300 WM and also did some temp testing and found what Alliant said to be true..... it's not as good as some but not nearly as bad as others so moderately temp sensitive is a good description.
I know do one custom ammo maker who uses it extensively with very good results.

Who is the ammo maker?

 

[upacreek]

162 eld-x/ 4000-mr/65 degree powder
65 3093
65.5 3165
66. 3180
66.5. 3183
67. 3206
67. 5 3211
68 3231. Ejector mark
68.5. 3245 ejector/primer crater
69 3294. Ejector/primer crater

 

[grouse]

Wanted to bring This back up. Seems like this is one of a handful of powders available locally. Anymore insight to this powder? Thanks

 

[grouse]

Anyone ?

 

[venatic]

I use it enough that I just picked up another 8lbs as I was getting down to my last couple pounds.
Great powder for top speeds in 6.5 Creedmoor and also good in 300 Win Mag.

 

[Hugnot]

I use 4000MR in my .243 W with 87's, & 105's and in my .300 WM with 178's, magnum primers (CCI 250 & Fed 215). 4000MR has also worked out in my 7.7 twist .22-.250 with Hornady 75 hpbt's. I would anticipate some elevated pressures at 90*-95* so I plan to use RL16, H4350 or StaBall for hot weather rodent shoots. As for hot temps 4000MR could not be as bad as H414.