SkullKeeper
AH elite
***CORRECTION…these weigh 1.0 gr each (a little over 1 inch long)
The proponents of dacron are using 3031 and RL15 at low pressures, just enough to get regulating velocity. They are then meticulously weighing their dacron for 1gr or 1.5gr to ensure they are not allowing variances in pressure.
Dacron should be treated with the same respect as powder. .5 grains variance in either can create an unsafe condition
I have always heard that your filler weight (in my case either kapok or a foam plug) only adds to your projectile weight, and has nothing to do with the powder charge or any significant pressure increase. RL15 or 15.5 is THE powder for a 450#2 IMHO, loading with North Fork bullets, and I’ve not noticed any pressure issues (I do not have a way to test pressure, just going by physical results from spent cases).
I did once see a graph showing pressure changes with different wad material. Aside from different wads materials giving a different average pressure, some wads had a massive variation. If I find it again, I’ll post it.
Oh ! Gotcha ! Quite interesting for sure !Good to know. The unique thing about my rifle is oval bore rifling. In case you don’t know what that is, in the early 20th century it was a tech battle to make the best rifling. At the time, mercury powders corroded barrels horribly and they tried many patents: hosford, valley and hill, cut rifling, oval bore, and a thousand others.
Why that matters to me: my rifle looks like a shotgun if you’ve had a few drinks. First look down the bore it looks smooth. Take a closer look, and the bore is egg shaped and rotates as it goes through the barrel, introducing spin. (No lands nor grooves) It was ingenious at the time because you could clean the fowling easily. Because of this, I’m trying to reproduce the original loads with woodleigh and kynoch bullets so regulation is similar. A wad may help versus Dacron that would cause more blow back.
Indeed. So imagine what is going through my head? I can’t use modern solids with their driving bands because the lower pressure isn’t what an oval bore wants. Then think of the wads, I don’t want Dacron where gas can pass through a portion, I need a wad to ensure equal pressure. Then think of the bullet, I want an original Kynoch or a woodleogh replica because they were terrible, barely hugging the bore instead of a modern, longer bullet that has a better SD and BC but barley grabs the rifling.Oh ! Gotcha ! Quite interesting for sure !
What double do you have now ?I have found the posting on this site to be vey informative regarding filles. For about fifty years I have been loading reduced loads and if I used a filler it was Kapok. I'm not sure what it started out as but it is from some plant and was in general use as sleeping bag filler prior to Dacron. However, all of my loads were for centerfire single barrel, generally bolt action rifles. In addition I used powders designed for low density reduced loads, primarily SR 4759. My main concern was the transition from the cartridge base to the bullet base. If the powder is ignited and it gets a head of steam built with no resistance until it contacts the bullet base, it seems to me that this would be the equivalent of an obstruction in the barrel. I understand that this is what causes "ringing" in barrels. Back to the point- Since I am working with my first double rifle- one that is over 100 years of age- I am developing loads for it that do all of the things I've done with bolt rifles but adding to that, trajectory regulation as well as respect for the rifle. Thanks to the contributors who have helped in this endeavor.
Very nice !Double Rifle is a John Rigby 1910 470NE
Double shotguns: Parkers, Merkel, Winchester, Browning.