Opinion of IMR 3031

[Scottish Highlander]

Hi everyone I have started a reload exercise to try and get a good load with the IMR3031 powder. Im shooting it with my 308 Tikka and the bullet is the Hornady 168 grain A-max match bullet. I've made up 4 different load weights to test fire tomorrow at a target.

37 gr, 38 gr, 39 gr and 40 gr loads.

My plan was to test fire them at 100 yards and see the group. I've set the bullet 0.080 inch back from the lands which converts to 2mm. The 3031 powder is the only one I have just now and that is the reason for my question regarding that particular brand but if anyone can suggest a better powder I would love to hear there ideas. In the long run I am going to push the distance out to 600 yards or further but I want to get a good reliable load before I stretch my distance....

Thanks Jamie

[Slamfire]

I was able to purchase two cans of 1960’s IMR 3031 from an estate sale and was able to test it for use in my match rifles. It appears to be slightly faster than IMR 4895. The 308 cartridge was designed with IMR 4895 as the propellant and many matches were won with 168's and IMR 4895.

I shot some excellent groups in my testing, for me, the lot I have, 40.0 grains gives me an appropriate velocity and accuracy combination which I could use in my M1a, and that is what I used as an across the course load to 300 yards. One old gray beard had recommended a load of 39.5 grains, my load is within lot to lot variation. From the groups I got, IMR 3031 is quite accurate.

According to Philip Sharpe's "Complete Guide to Handloading" IMR 3031 was introduced in 1934 making it one year older than IMR 4064. I know this was a popular target powder in the 308 and in the 30-06 as I have seen loads and shooters using it.

While 3031 is capable of excellent accuracy the stuff is as long grained as IMR 4064. I don’t care for long grained powders, they don’t throw well: the throw to throw variation is large, and the stuff is even more likely to bridge in my Dillion powder funnel. There are more advanced short grain powders out there, such as N140, N540. If you can get your hands on Varget, give it a try, it is an outstanding powder.


Ruger M77 MKII
26 " Barrel 1:10 twist

168 Nosler 39.0 grs IMR3031 wtd Lot FE23B LC72 CCI#34OAL 2.80"
27-Nov-06 T = 60 ° F

excellent accuracy nice rounded primers

Ave Vel = 2513
Std Dev = 14
ES 51
High 2534
Low 2483
N = 10

168 Nosler 40.0 grs IMR3031 wtd Lot FE23B LC72 CCI#34 OAL 2.80"
27-Nov-06 T = 62 ° F

excellent accuracy nice rounded primers
best group of IMR 3031 series

Ave Vel = 2568
Std Dev = 15
ES 48
High 2590
Low 2542
N = 10

168 Nosler 41.0 grs IMR3031 wtd Lot FE23B LC72 CCI#34 OAL 2.80"
27-Nov-06 T = 62 ° F

excellent accuracy some flat, some round primers, easy extraction

Ave Vel = 2619
Std Dev = 15
ES 52
High 2654
Low 2602
N = 10

note, the LC72 brass was on fifth reloading, fifth sizing

[Brian Pfleuger]

I like 3031. I use it in 7mm-08, .243AI and recently in 6mm Rem. It's relatively fast and reduces muzzle blast/pressure in my 15" Encore. According to QuickLoad, it should produce near max velocity of any powder in 6mm Rem and .243AI with light (55gr) bullets. I haven't finished my testing though. It was at one time THE go-to powder for .243, but I think 4064 has surpassed it.

Incidentally, in terms of searching for accuracy loads, a full grain jump is too much with charges in the 40gr area. You want to use no more than 1% increments, which would be 0.4gr.

[thallub]

For decades i've used IMR 3031 in .308 and .30-06 with 150 grain and lighter bullets. IMR 3031 is my favorite for .223/5.56mm with 55 grain and lighter bullets. Also use it in several other calibers.

[Scottish Highlander]

Thanks for reply's, Slamfire....your load below
168 Nosler 41.0 grs IMR3031 wtd Lot FE23B LC72 CCI#34 OAL 2.80"
27-Nov-06 T = 62 ° F
exceeds the Hornady hand book list for 168 gr bullets in there Hornady brand.

They state the max load is 40.2 grains and to use max loads with caution!!

For that reason I will shy away from the 41 grains just now as i don't have that kind of experience with reloading yet to build up to an over max allowed sample. Maybe in Nosler they allow an extra .8 grains with the load but I don't have the Nosler manual to hand ..

Brian once I shoot this loads today if this wind dies down I'll hopefully find a sweet spot in between the grains and then I'll do as you say and fine tune by .4 grain incremental to see what I get. I relies @100 yards I might have a good group on a particular load and it might open up and be bad at 300 on wards but field testing will hopefully find me a good load for the 3031.

P.s: I test fired 38 gr on the 168gr Hornady and it was a 3" group @100 yards...... I have brought the coal out by 1mm and will test fire that load today again as it's closer to the lands now and I might get a better accuracy from it that way

Thanks for replys

Jamie

[oneoldsap]

Yes sir , that's why you don't ever want to shoot someone else's load , without working it up yourself . As to the .308 being developed with IMR-4895 . Not hardly ! The .308 was developed with Winchester ball powders . W-748 is as close as you can get to original , and it just may be . BL-C 2 is pretty darned close too , and a great choice for the .308 Win. I've never used a powder faster than IMR-4064 , and that was with 150 Gr. Bullets !

[chiefr]

I use it. One of my base powders. Great in 45-70

[Slamfire]

As to the .308 being developed with IMR-4895 . Not hardly ! The .308 was developed with Winchester ball powders . W-748 is as close as you can get to original , and it just may be .

I read that the 308 was developed with IMR 4895 but I cannot find the reference. I have examined DTIC and the web and have come to the conclusion that you may be correct about the 308. Winchester created the commercial version of the 762 Nato: the 308 Winchester. The Army developed the 762 Nato. It makes sense that Winchester used its own powders in the commercial cartridge.

As for the identification of the original propellant used by the Army to develop the 762 Nato, I have not found that. I have looked at data for the National Match cartridges and for the vast majority of National Match ammunition IMR 4895 was used for Garands and M14 rifles. I have not found another powder being used for the Garand though I did find one reference to experimental 762 NM ball ammunition loaded with a ball powder.

]

I will continue to say, because it is reasonable, to state that IMR 4895 was the powder that was used in the development of the 762 Nato, unless you can find a good reference that shows otherwise.

As for my IMR 3031 data, I found no issues with any of those charges and I did decide on 40 grains to use for the short range. I had no extraction issues, no pierced or leaking primers, but, I said I decided on 40 grains and I shot up almost 2 lbs worth in competition and it worked without problems.

As always, use data for guidance, your lot, your rifle, your brass, your primers, are different.

[GeauxTide]

3031 is a good, old standby, but a little fast for top 308 loads. Today, Varget is the absolute best. 46 grains for 150s and 46.5 for 165s.

[reynolds357]

Varget is maybe absolute second place. Big game is "absolute best."

[Scottish Highlander]

Well I test fired the load with the A-Max Hornady 168 gr. Turns out that 40 grains of IMR 3031 is the Dogs Cahoonas .

@ 100 yards I shot this group in wind and rain. All 4 shots are touching and the 5th to the side is actually a 39 grain shot but I think I pulled that one off target.

[Scottish Highlander]

This is the 38 grain group @ 100 yards....considerable difference really ..

[Brian Pfleuger]

Better make that pudding bowl bigger than 3 shots before you celebrate.

I shoot 3 shot groups a lot, almost always, but it takes more than one or two to get a real feel for the loads consistency.

[Scottish Highlander]

I hear yah Brian....

So set me the challenge and I'll try it

What do I need to do ?? Drill the bull till there's no more ink left on the paper

[Brian Pfleuger]

Nah.

I'm one of those who gets pretty annoyed by the chants of "Your 3 shot groups don't mean anything!" so I'm not about to tell you to go out and shoot 30 shot groups...


BUT one three shot groups DOESN'T mean anything. You need more.

What I generally do is take that gun and load out whenever I go shoot. I shoot another 3 shot group or two, or even 4 or 5 shot groups sometimes but not usually.

Eventually, I get an idea of what that gun/load will do across a range of variable weather conditions.

I know it will consistently put 3 in "X" MOA, no matter how big 30 might be.

[Scottish Highlander]

Ok sounds cool to me.

Well for the record it was p+ssing down and we have a storm here with 30-40 mile an hour gusts ...and I had to shoot test at a different venue to shelter from the wind a bit. When the weather settles down a bit I'll give it a more broader test. If I have a good load what sort of groups should I be looking at out at 200-300 and 400 yards... Surely I wouldn't be grouping them like that out at 400 would I or is that whats expected at competition level

[hooligan1]

Fire at least ten of those 40 grain loads Highlander and if it's as nice as the group posted, I'd write that load down in my littl black book.
very nice man!

[Brian Pfleuger]

Groups usually grow at least 10% in MOA terms per 100 yards.

So, if you're shooting 1/2 MOA at 100 yards, which is 1/2 inch, you'd be shooting AT LEAST 0.55 MOA at 200 yards, which is 1.1 inches.

The equation is

(100 yards group MOA size)*1.1^(increase in hundreds of yards)

in other words, if you shoot 0.5MOA at 100 and you want to know the SMALLEST likely expectation at 400, it would be 0.5*1.1^3, which would be 0.665 MOA.

Keep in mind, this is best case scenario, pretty much.

[tahunua001]

I have no horse for this stable but I would just like to point out that the ONLY powder that is available at all of my LGS at this moment is 3031....

everything else is VERY hard to get a hold of.

[A pause for the COZ]

Right now for me 3031 is still a tweener powder.

I have tried it in my 30-30's, Works great but WC844 (H335) does a little better and I have 50 pounds of it.

tried it in my 223 loads. Works but again WC844 is better.

Tried it in my 308win. Works, but Varget, RL-15, H4895 perform better.

Tried it for cast loads in 30-30, 308, 303 britt, 7.62x54.
Works but 2400, Red Dot, and RL-7 work better.

Still trying, I have 10 loaded up for 125gr FMJ in my finicky 303 Britt to try.
Watch.... As soon as I get to the bottom of this pound I will find a load for it.

[Bart B.]

One of the first 7.62 reloads used by military teams for was a Sierra 168 gr. HPBT on top of 39.0 grains of IMR3031 for short range. This load was found to be very successful for matches where it was allowed. It would eventually be loaded by Federal in the mid 1970s for the Marine Corp team; becoming the Federal Gold match load in 1990 (though bumped up to 41 grains of IMR 3031, with a subsequent shift to IMR 4064. The USN teams also used it.

Although dirtier than IMR4895 and barrels needed more frequently cleaning, 3031's accuracy was as good as could be had. Handloads with new Federal cases as well as Federal's match ammo would shoot inside 5 inches at 600 yards in well built M14NM and M1 rifles. When IMR4064 was used, accuracy was a little better as well and barrels didn't need cleaning as often.

==========

Brian says groups usually grow at least 10% in MOA terms per 100 yards. I agree. Note all the fired groups are zero MOA at the muzzle, aren't they? Then the bullet jumps off the bore axis a tiny amount due to its unbalance (centrifugal forces) and gas jetting from the crown edges (crowns are not perfectly uniform and exact for each shot due to bullet and powder residue left from the previous shot) on the base of the bullet (bullet heels are the same as muzzle crowns dimensionally).

[Slamfire]

One of the first 7.62 reloads used by military teams for was a Sierra 168 gr. HPBT on top of 39.0 grains of IMR3031 for short range. This load was found to be very successful for matches where it was allowed. It would eventually be loaded by Federal in the mid 1970s for the Marine Corp team; becoming the Federal Gold match load in 1990 (though bumped up to 41 grains of IMR 3031, with a subsequent shift to IMR 4064. The USN teams also used it.

I would agree about 39 grains out to 300 yards, I used 40, but I needed more velocity than 40 grains would have produced at 500 or 600 yards.