311041 what next?

[willwork4ww]

I have been trying to shoot 311041 in a pair of micro groove .30WCF's. This is my first attempt with MG. Here is what I have tried so for:
Mold drops .311. Gun' s slug .308. LBT Blue.
ACWW sized .309 - 4895 varying charges--mediocre accuracy 3-4" @100
3031 varying charges--mediocre accuracy 3-4" @100
Benchmark same story
BLC-2 same story
H-4350 34.0grs, filled to the shoulder better accuracy in one gun, not the other
H-4831sc 33.5, 34.0, 34.5, 35.0 grs best accuracy with 34.0 grs filled to the shoulder. Also tried 4895, 3031, Benchmark with dacron filler, all of the above with acww and wdww. No difference between the two.
34.0 grs H-4831sc sometimes shoots 4 or 5 shot groups of 3/4" at 100 yards with irons but other times sprays 3'' groups seemingly depending on nothing more than a whim. Yes, I can shoot irons. My .45-70's will hold 1" or less at 100 with LBT 458-400M. I have consulted the Nyack Kid who is a currently a close neighbor and he had no more idea than I did, other that maybe micro groove isn't too cast bullet friendly. Is it the bore ride design, micro groove combination?
I have not tried any pistol powders as I would prefer to keep load density fairly high. WLR and CCI 200 primers. Velocity runs 1800 fps for the 4831 and between 1700 and 2050 for the other powders. The 4831 periodically throws a four shot group of 5/8- 3/4" with one flier opening the group to 2 1/2". Could this be an overlube condition? Any ideas? Scrap the MG?

[45 2.1]

Try sizing to 0.311"

[Bass Ackward]

WWFWW,

There are many possibilities here. It sounds like primer to me. There are two ways to go. I would recommend a magnum pistol primer with the H-4831 load because they are more consistent from shot to shot. If you have some plastic shot buffer for shotguns, I would try that too in just enough to maintain compression, but it isn't really needed at those pressures / velocities. Just realize that with a pistol primer that you may need another grain of powder to generate the same pressure. If you go to a magnum rifle primer to get ignition you may have to drop up to 2 grains.

I see that you are questioning your lube. If you shoot better on hot days than cool, then you have a lube problem. If your fliers are less distant on a hot day than cool, you have a lube viscosity problem. Just so you know.

[BABore]

Definitely try bigger bullets 0.310 or 0.311. Marlin MG barrels are notorious for liking them bigger. That would be my first stab at correcting things.

Assuming bigger bullets don't cut it, look at another lube. I have several rifles that prefer LBT lube, and several that hate it. Hot or cold they will group a few shots tight, then throw a flyer with no pattern. IMR 3031 and std. rifle primers should be a winner if other things are right.

[Bass Ackward]

Yes. Sorry. I miss read that. I only saw the .311. I would go diameter as my first choice. It could be .310 but likely .311 won't hurt anything either.

[w30wcf]

willwork4ww,

ACWW is not a hard enough alloy for 2,000 f.p.s. in your .30-30 with the 311041 bullet......at least in my experience.

I have worked with 3 different micro-grooved .30-30 Marlins (.308-.3085" groove diameters) and have achieved 2 M.O.A. and better consistantly using the 311041 cast from 50% w.w. / 50% lino and a capacity load of H414 powder / WLR primers.

Bullets were lubed with 50/50 Alox/Beeswax and sized .311".

Capacity loads of H4350E and H4831SC produced similar, but not quite as small groups.

Try water dropping your w.w. bullets and size .311". You should see a definite improvement unless your barrel bands are too binding on the barrel / magazine..... in which case, remove them, and open the barrel portion up slightly using a wooden dowel and some fine emery cloth.... just enough so that a piece of paper will just slide between the band and barrel.

Good luck,
w30wcf

[Char-Gar]

Da boys are right...Size those bullets .311 and watch things improve.

[willwork4ww]

Thanks for the advice guys. I had a sneaking suspicion larger was the way to go.
BA- thanks for the lube lesson. To tell the truth I hadn't paid much attention to temperature during my testing sessions, but as I recall temp and humidity have varied quite a bit. Will give this some studying.

w30wcf- With the ACWW's did you find leading to be a problem, or just poor accuracy? Mine don't lead but they don't shoot either. I do have a line on some linotype now, so I will give that a shot.
I installed a sourdough front on one rifle tonight, that should at least let me hold more consistent elevation than the bead so that should eliminate one more variable.
I guess I'll be honing a die out tomorrow then.

[w30wcf]

willwork4ww,

In answer to your question:


w30wcf- With the ACWW's did you find leading to be a problem, or just poor accuracy?

I found no leading, but poorer accuracy at 2,000 f.p.s.

I reread your post and I found that I missed the fact that you had poor accuracy at 1,700 f.p.s. I have found that ACWW Lyman 311041's will shoot accurately up to about 1,800 f.p.s. One load my Winchester '94's really liked with that alloy / bullet was 24 grs. of 4895 (1,700 f.p.s.)


34.0 grs H-4831sc sometimes shoots 4 or 5 shot groups of 3/4" at 100 yards with irons but other times sprays 3'' groups seemingly depending on nothing more than a whim.

Based on your results with H4831SC, I would suggest weighing the bullets you will use for future accuracy testing to be sure that you don't have any with trapped air / contaminants which can destroy accuracy. I would shoot for + - .3 grain. Keep the ones that are +- .5 in a separate pile. Any thing beyond that, I would keep for casual short range plinking.

Also try .311" bullets. Prior to honing out your sizing die, you could apply gas checks and run the bullet just far enough into your .309" die to reduce the g.c. diameter to .311". You could then hand lube them to try shooting a few groups.

If not much improvement is noted, try shooting some jacketed bullets. If accuracy is still dismal, then the barrel bands just might be the culprit(s).

Good luck,
w30wcf

[willwork4ww]

w30wcf -
Regarding your results, I too have obtained good accuracy from 24 grs 4895, however this only mustered 1550 fps in my guns. I should have stated in my original post that I have obtained excellent accuracy below 1700 fps. For example 21grs 4895 for 1315fps, 23grs for 1450, 24grs for 1550, and 25grs for 1600. I was preferably going for good accuracy at 1800 fps + as I hoped to hunt with this combination. I have been weight sorting my bullets to +/- .3.
Accuracy was good with jacketed pills before I decoppered and went exclusively to cast so I think the barrel bands are ok, although that is an interesting theory. I will try your sizing suggestions tonight and try to get some groups shot if it will quit raining this week. Thanks for the help, and I'll keep you posted.