load density

[white eagle]

Do you see any advantage to keeping the load density percentage up near 100%
what I mean is the dead space in the case.... by seating the boolit deeper in the case to slightly compacting the charge :?:

[Char-Gar]

That is an interesting question without a pat answer. When dealing with jacketed bullet and slower powders I would say yes. I tight powder column does contribute to uniform ignition and therefore velocities and accuracy.

But when we talk about cast bullets and the fast powders we so dearly love, I would it depends on the powder and how position sensitive it is. All powders are position sensitive to some degree, but some really need a filler to keep the charge together and against the flame.

So, like most things having to do with firearms, the answer is "it depends".

[JeffinNZ]

Chargar is right. If you check out the load data in CBA matches very few would be anywhere near 100%. I get AMAZING accuracy in my .303 Brit with 13.8gr of 2400. That's got to be about 25% at best.

[white eagle]

I have read here a few times that some like or find the best accuracy when the boolit sits directly on the powder charge or even slightly compresses it
my concern was actually with seating depth
I have one boolit in particular(MP,300gr. 44 cal) that has numerous crimp grooves whereby changing the o/a to various lengths
a charge of powder say 18.0 gr 2400 in 44m my have a dead air space or have the boolit on top of the powder column
trying to figure if it is really worth the concern

[Old Caster]

I think fast versus slow powders (full vs half full) might have other effects also. A slow powder at the same velocity as a fast almost always feels like less recoil. This is only felt recoil because the foot pounds of the recoil has to be the same if the velocity is the same. It is just a matter of time. The effects on the bullet are the same also in that the bullet takes off more suddenly with the fast powder. I think it depends on what you are looking for and what your results are also and I don't think a blanket statement could be made that one is better than the other. Some like Trail Boss are fairly fast but still bulky to fill a case.

[fredj338]

I think fast versus slow powders (full vs half full) might have other effects also. I think it depends on what you are looking for and what your results are also and I don't think a blanket statement could be made that one is better than the other. Some like Trail Boss are fairly fast but still bulky to fill a case.

Most definitely! Compressing the right powders in the right volumn size case is the key. All black powder loads are compressed & known for extreme accuracy w/ lead bullets. A compressed charge of slower smokeless should yield sim results. When loading jacketed in my rifles, I lean to 100%+ density loads for best accuracy.

[HORNET]

You do have to be kind of careful doing this. Some powders react strangely with even light compression. Using Trail Boss, it is specifically recommended NOT to provide any compression whereas I've seen reports on here that Herco prefers light to moderate compression. Same kind of thing applies with different manufacturers of Black Powder. A little Dacron can do wonders for ignition consistency without actually compressing the powder if you're worried about it.

[bobthenailer]

the only cartradges that i load for that are sometimes loaded to100% load density for max loads are the 454 Casull with 296, h110, ect and the 45/70 with black or 4831

[PacMan]

White eagle i may be missing the train here but i think that your question is seating depth and presure.
Given the same load/grains powder the deeper you seat the bullet the more presure will rise.Like charger said accuracy just depends and slow vers fast throws in another equation.
Take Lil Gun and load to a compressed load and it is easy to get the SD numbers down to around 5-10 fps but in my rifles 357 and 454 the accuracy goes out the window.

Unlike most i prefer slower powders and buy using them i fill the case up better which i like and do feel that it helps accuracy up to a point.

[44man]

That is a good question and I never gave it much thought. The reason is I just use the groove where the boolit fits the gun and work loads.
Seated deep should use less powder in the end for accuracy. Air space might be the same????
Too much space with a slow powder is no good and seems to mean little with a faster powder until powder moves back and forth a lot in the case.
What does primer pressure do when a boolit is deeper? Does the boolit move out anyway with a high pressure primer and increase space? As brass has the internal capacity reduced, primers start to cause problems.
There is always some fly in the ointment and all we can do is speculate.