Retumbo...

[BCB]

For some reason, I have always preferred the slow burning powders for my bottleneck cartridges and cast boolits…

I like the “fill to the base of the boolit”, use a magnum primer, and go for velocities of generally < 1850 fps. Less than that in cartridges the size of the 30-30 Winchester and 7-30 Waters…

My most recent project has been the 30-40 Krag and I have been using WC-860 and WC-872 with good results. But, the military stuff burns filthy and leaves residue all over the place—not just unburnt kernels of powder…

So, I thought I might try Retumbo as QL indicates a 100% density load in the Krag would only be producing 19000+ psi. I am hoping the extruded powder might burn a bit cleaner and have better ignition…

Regardless, anyone use this powder for sort of the same reason I wish to use it for…

Thanks…BCB

[bgmkithaca]

I have not tried this but quickload with the heaviest cast bullets indicates it is still only burning about 70% of the charge. My money is on a real dirty burn with a lot of unburned powder. It dot look like you are gaining anything to me other than wasting a lot of powder. Look at something faster burning- there are a lot of choices that are MUCH BETTER and you can still have a case full of powder but a cleaner burn, There isn't much out there that burns well at 19000 psi and you won't be able to get near a case full with any powder that does.

[Rcmaveric]

I like to maximize economy and accuracy. Using a mag primer with a slower powder just makes that powder act like a faster powder. To have better ignition and more clean burning then you need a faster powder. Switching to an slower powder will make even more mummies and be just as dirty. I have just started searching for a slower usable powder. I would love a powder that fills the case and peeks at about 35kpsi. To give a pick pressure latter on and keep a higher sustained pressure.

I like to experiment with powders aswell. To me it seams my boolits have a preferred pressure zone. Most of my boolits like about 30-38K psi. X amount of Red Dot, X amount of 2400, X amount of Tight Group, and X amount Reloader 7 all give me about 38k PSI and produce sub MOA accuracy. Only difference is case fill and price per charge and velocity. As of now slowest powder that works accurately for me is Reloader 7. I tried some 4064 but i hypothisize it needs a heavier boolit and didn't produce the desired accuracy in my various cartidges. I got some H4895 on the shelf waiting because of what Hogdon says about it. I want to try some 3031 from what i have read around on various articles.

I get what your doing. Giving a gentler launch and sustaining pressures. Aswell as keeping optimum case fill for accuracy and safety. Problem with slower powders is the lower friction value of lead prevents the pressures from getting to optimum for the slower powders to burn. IMR4064 produces exceptional groups and velocity for my .270 Win with jacket 130 grain bullets. Not so good performance with a 135 Gr cast bullet or 6.5 Grendel. Even barrel dwell time is shorter. I have an idea about 4064 a heavy for caliber bullet that may produce the desired results but i think 3031 would be better. This would either prove or disapprove my earlier hypothesis.

Curious about others thoughts and opinions. Since i am research slowest usable powders anyways.

[Retumbo]

Yes?...

[BCB]

Yes?...

Well, your name seems to indicate you might use Retumbo...

Do you use it with low pressure loads and in what cartridge are you using it with...

Thanks...BCB

[earlmck]

Heck with the expensive Retumbo. Just drop a grain of Unique at the bottom of the case, fill to compression with your slow ball powder and shoot much cleaner. You can do away with the magnum primer, too.

You might have to put up with more velocity than you wanted, however.

[Rcmaveric]

Funnily enough, I was actually just reading about duplex smokeless loads a few days ago. I am not sure I am experienced enough to pull that off safely. I think it would be wiser to keep playing with powders. I would would just switch powders before I would try that.

[BCB]

Funnily enough, I was actually just reading about duplex smokeless loads a few days ago. I am not sure I am experienced enough to pull that off safely. I think it would be wiser to keep playing with powders. I would would just switch powders before I would try that.

Yep, I have read of duplexing loads on this website and I really don't have an opinion one way or the other on the safety of it. I know that I am not going to attempt it, but I certainly don't condemn those who do it and have found it effective...

Good-luck...BCB

[earlmck]

Sheesh fellers -- one grain of Unique doesn't qualify as a "duplex load": that is just barely an "enriched priming compound".