Powder size versus velocity

Discussions of powders, bullets and loading information.

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SSShooter
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Re: Powder size versus velocity

Post by SSShooter »

A 439gr BACo Money bullet shot well in my 14.5" twist 32" long GM barrel at 800, 900 & 1000yd with 65-68gr of 2F Swiss.
Glenn
SchuetzenDave
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Re: Powder size versus velocity

Post by SchuetzenDave »

With the faster velocities from the Swiss FFFg I achieved the same result with my 422 Paul Jones Creedmoor.

53.7 grains of powder compared to 68 grains means my powder costs were 26.6% less to achieve the same result.
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JonnyV
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Re: Powder size versus velocity

Post by JonnyV »

So you got a higher consistent velocities with 3F powder?
SchuetzenDave
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Re: Powder size versus velocity

Post by SchuetzenDave »

Yes Quite consistent since all of the powder is completely consumed in the barrel, therefore no variations in pressure from different amounts of unburned powder exiting the barrel.
Inconsistency is due to the amount of excess powder not burned that ends up being expelled outside the barrel.
Also the excess powder not consumed also contributes to increased fouling.
I get complete combustion of the FFFg resulting in a fine ash which cleans out well by the lube as opposed to the coarser ash containing unburned powder from using coarser grained BP.
I totally disagree with the Motherhood statement that FFFg causes more fouling.
I found it was better to achieve increased velocities by using finer powders; opposed to packing excess powder into the case which does not all get consumed in the barrel.
martinibelgian
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Re: Powder size versus velocity

Post by martinibelgian »

Yes, but - it's not a reply to your question - Dave is referring to his use in the 40-60 and 40-65, moderate-capacity smaller calibre cases, while you are asking about 45-90 and 45-100, 50+% capacity increase and larger calibre. Even though I get best results and least fouling in my 32-20 with 1 1/2Fg swiss. I never had best results with 3Fg in any of my cartridges, be it 32-20, 45-70, mo.2 Musket - and I never even tried the cavernous 577-450 with such a fine powder, a waste of time... And also avoidance of a sore shoulder!
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JonnyV
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Re: Powder size versus velocity

Post by JonnyV »

Good info!

Right now I have a large amount of 1.5 F Swiss powder on hand. I also have smaller amounts of OE 2F and 3F. My bullet right now is a 540 grain money bullet with micro lube grooves.

I guess the first thing I can do is load up some 10 round test lots with my current bullet, and chronograph them and just see what the difference is. Since OE is out of production, my results won’t exactly match what happens with the Swiss but maybe it will be a good indicator…
martinibelgian
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Re: Powder size versus velocity

Post by martinibelgian »

FWIW,

As to fouling and coarse granulations: I shoot my Steyr-Martini no.2 Musket (about 45-90 case capacity, but a BN case) in a period military rifle with Swiss Fg, no cleaning between shots, PP bullets (albeit with grease cookie), blowtubing only.

After shooting, 2 wet patches, the 3rd is just about clean as in virtually no trace of fouling on the patch. Just goes to show....
I wouldn't even think of using 3Fg in that cartridge, which is essentially a 50-90 case at 2.3", necked down to .45.
gunlaker
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Re: Powder size versus velocity

Post by gunlaker »

That bullet should shoot the lights out in a Shiloh .45-90 with around 80gr of 1.5. My 1:16 twist rifle works best with Swiss 1.5 and the 1:18 twist rifle is very good with OE 1.5, but I don't think I've tried Swiss in the slower twist rifle.

Chris.
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