Filler with WC 860

[mto7464]

Would like to use some COW (cream of wheat) as a filler in a k31 case to compress the charge. Does this sound safe? I have never tried COW before since I never had the need.

[Ricochet]

Reportedly that stuff can set up to a pretty hard solid when left compressed for a while. I've never tried it.

[redneckdan]

I tried 5 gr of unique under 35gr of 860 under enough cornmeal to fill the case, the projectile was a 170gr flat nose sans gascheck. Accuracy was great but there was always a hard clump of compact cornmeal inside the case against the shoulder.

[Maven]

I also dislike the amount of unburned WC 860 enough to try bran fiber (I think cornmeal will also work). Unfortunately, family commitments & illness haven't allowed me to test this yet, but for the 7.5 x 55mm, here's what I recommend:

47grs. - 48grs. WC860 + LR Mag. primer + 0.7cc (Lee Dipper) Bran + CB weighing >160grs. Store these loads with the primers facing you so there's little chance of the filler migrating into the powder charge.

Btw, bran doesn't seem to form the hard plug that COW does, but I'm not sure whether it's a property of the bran itself or the latent moisture content of the filler being used.

[Maven]

I just posted the results of testing WC 860 with a bran filler on the Surplus Powder board. In short, it's not worth the effort with 860 and, accuracy was markedly worse with the filler (only 0.7cc). No pressure signs, but just as much unburned powder and, as already mentioned, poor accuracy.

[mto7464]

I too just went out and shoot some this AM. Not much difference. I tried some with a booster of Herco and it did shoot cleaner but accuracy was poor, 5" at 100 yards. My load with 4064 sans filler, with one really bad flier if I don't include, gave me 2" groups. screw the WC860 for now.

[Maven]

mto7464, WC 860 with no filler or booster is as accurate as any other powder I've tried, but it IS dirty. IMR 5010 an extruded powder similar to 860 in burning rate, on the other hand, responds very well to small amounts of cereal (bran) and poly- fillers. I.e., while they don't eliminate the unburned powder in the bbl., they do tame the extreme velocity spreads & standard deviations common to 5010.

[curator]

My favorite CB load for the 6.X55 Swede is 35 grains of 860. Without filler I get enough unburned powder granuals to make little dents in my brass and sometimes cause dificulty in chambering. I started using Plastic Shot Buffer as a filler and now do not get unburned powder left over in barrel and chamber. Accuracy is actually a bit better than without filler. Velocity is almost 200fps more with the PSB as well. The only downside to this is the extra step and the burned plastic smell at the range.

Having played with various fillers over the ages, I really like the PSB for bottleneck cases. It doesn't cause pressures to skyrocket like cream of wheat sometimes can, but must be measured carefully as it is not very compressible. I usually set up a spare powder measure to despense PSB (to the bottom of the bullet, exactly) so I don't have difficulty seating bullets. Unlike other fillers, PSB almost always can enhance accuracy if you take the time to work up a load. In most cases, I have found that reducing the original (unfillered) charge a few grains results in improved accuracy.

[mto7464]

Maven, I sure haven't found a load of 860 that shot very well. I have tried just about everything now is this rifle. I think I will switch and try in in someother caliber.

Curator I didn't think of shot buffer. Think I will order some. The COW doesn't smell that good either.