Dear Roscoepc !
My answer to your question is phisical-chemical , the total burn time of a charge is affected by the burn-rate and the distance the flame has to travel in the material (you have to multiply the two) , the prsure-peak timeing is built relatively to the answer to the mentiond equation and the prsure-peak-fortitude is affected by it too and the surface-erea and the volume of the chamber (all 3 variables) .
So if the surface erea ignited is larger in one case - no doubt the presure-peak will be differnt ! .
So if the powder is filling the cartridge totally , the surface-erea ignited is the cut-width-erea of the cartridge, and if the powder is less in volume than it can get a lot bigger ignition-surface (cut-length-erea) of the cartridge .
To my humble opinion, if you will use a solid filler on top of the powder charge you will eliminate the possibility of higher presure-peak.
Good luck
O.g.
Excellent answer!!!! DING DING DING DING we have a winner!!!!!
The OP asked "In say, the 17gr of Titegroup mentioned, there is a certain amount of pressure produced when the powder is ignited.. How would the position of the powder in the case affect the pressure produced?? That is the question I'm asking you guy's! How could the pressure increase enough without a double throw of powder because I'm thinking that what happened: A double throw!!!"
The same thing happens in rifle cases with fast burning powders. The min/max charge of a fast burning powder like reddot in a 30-06 case is around 4gr with most bullets. The fast burning powder is spread out the length of the llloooooonnnngggg case and the powder flashes off the whole length of the case changing the burn rate/pressure.
When I look at different powders and I'm trying to decide if I want to test them. I'll look at the powders burn rate, if it's a high energy powder (high nitroglycerin content/also good for melting powder hoppers if left in them) and a lee powder dipper chart.
http://www.leeprecision.com/cgi-data/instruct/Dippers.pdf
This tells me the density of a powder. Over the decades I've had my best results with my reloads when I've kept my pistol loads in the 70%+ load capacity. So if I find that a fast burning powder that is extremely dense it tends to work better in small cases.
A good example titegroup vs clays:
Both are fast burning powders with similar burn rates. But the titegroup is allot denser, using a lee 1cc powder dipper;
titegroup ='s 11.8gr
clays ='s 6.8gr
The clays has 173% more case capacity for the came load compared to titegroup. (reddot is close to clays in density/1cc ='s 7.1gr).
This tells me that the titegroup would be better suited for small capacity cases & the clays would be better suited for large capacity cases.
I understand the op looking for a reduced load, I also understand other peoples concern about using a high density/high energy powder like titegroup for that reduced load. Personally I like to use these powders for plinking/powder puff/target loads.
clays 1cc ='s 6.8gr
am select 1cc ='s 7.5gr
trailboss 1cc ='s 4.6gr
Plinking loads of clays:
Clays ='s a fast burning powder that isn't very dense/better for larger capacity cases.
Plinking loads of bullseye:
Bullseye ='s a high energy fast burning powder that has a medium density/better for small capacity cases.
45acp's & bullseye
38spl's & bullseye (left 2 targets)
Anyway, hope this helps in answering your question about powder position and hopefully give you something to look at when you studying different powders.
O-ya, something else to look at. There was some mention of bullseye powder and problems. It used to be the "bad boy on the block" decades ago. It looks like titegroup wears the crown now. What alliant (hercules powder co) released back in the 60's to help reloaders understand the affects of bullet seating depths and powder charges (double charge) and how those things related to pressure increases/kabooms.
