horsefly,

  Ok.... I see where you're coming from, altho I think you're assuming that all BP lubes have fat in them, since there is no way you can create an organic material for an inorganic one. That's an assumption I can't make not knowing the composition of those lubes.

Barry,

  I certainly agree with you that a round bottomed lube groove with tapered sides is the way to go in casting, altho I never thought of it as being a help with slinging the lube off.

  I can't speak for other guys but I'll agree with you about the black ring around the bullet hole at the target and observe that all the time. But, what my observations have been is actual pieces of lube of the target face outside the the hole. This ring around the hole is not so noticeable with BP loads where you wipe out between shots, but is easily seen when shooting dirty.

  I suppose we could get into quite a discussion as to how the lube is applied to the bore side....... hydraulic or centrifical. I tend toward the latter as I don't recall ever digging out bullets from the backstop where the base was cupped, as some suggest for the hydraulic theory.

  The shear or compressibility of lube is something that we count on when bump swaging cast bullets. Without the lube in the grooves the bullet would collapse unevenly.

  When you say the consistency of the bore residue changes with Temp. & Humidity is this because the powder residue is mixed with the lube? I wouldn't think that smokeless powder residue has any component that would be affected by them. But then I don't know that for sure. Comments?

Your method of breech seating the bullet right after the shot is something I'll have to look into. At this point I always take care of the case first with both smokeless or BP. I can see your point about the fouling hardening and causing problems with smokeless, and might be something to consider when wiping out for BP to.

  What's your take on the other thread on hard vs soft lube?

PETE

Good morning, Pete;

Yes, I'm assuming that the lube has a fat in it.  Good BP lubes all seem to have some fat in them.  There are many kinds of fats including crisco, other vegetable shortenings, all (I think) of the cooking oils and a bunch of other things.

Y'all be good.

horsefly

PETE,

Sometimes I omit going in the great detail as my posts tend to get abit wordy.
 
With respect to humidity/temperature effects on the internal ballistics. These condition variables have more to due with the lube/power residue, most importantly humidity. Many shooters besides myself always seat the bullet into the rifling before charging the case. Testing across your chronograph should reveal this. Try both seating the bullet first and then after preparing your case. You should see more consistant velocities when the bullet is seated first. When the bullet is seated later you should see a wider MV spread and an increase in velocity. Of course the variance in velocity is dependant on conditions on any particular day. On cooler days, if the barrel is fired at random time intervals the consistancy of the lube/powder residue changes, this also causes velocity variations. For instance, run a patch through your barrel shortly after firing and note the resistance felt on the cleaning rod, then do the same after the barrel has been allowed to set for 5 minutes. Since my experience is with smokeless powders, I can't speak on the subject of BP effect.

Another condition I have obsevered. When dropping charges into the case using a conventional powder measure drop tube with an inverted cone I noticed powder clinging to the inside of the case neck, pouring the powder out, then tapping the case, about 3 grains of powder came out. On days with low humidity, less than about 50%, no powder is left clinging to the inside of the case. Before realizing this was occurring it caused me no end of grief trying to maintain tight MV tolerances. After making a new drop tube that fits inside the case neck and extends almost to the bottom of the case, erratic velocities disappeared on humid days. I now use the inside drop tube for all testing. As Claude Roderick would always say "tremendous triflings" can sometimes have a large effect. I should also add that I use a fine grain ball powders for testing, although this condition also occurs with powders like 4227.

Another reason to load the case after seating the bullet into the rifling is it resduces the chances of double charging a large case like the 32-40, in particular shooters like myself who do not use a wad over powder.

Temperature effects the burn rate of some powders more than others and possibly effects primer to small extent also. 

Barry

Barry,

  Gotcha on the wordy posts and leaving out some details. Seems I got my butt chewed last week because of this.  You can't tell everything, but, in my case if I don't get something, or feel there's more to it, I'll ask questions. Never did learn the trick of reading minds! 

  Testing whether a bullet seated before case prep and after will be an interesting test to do. As I mentioned, I've only done the case prep first. I can see the logic of it especially if the humidity is relatively low. Might be interesting to see if there's a point where it doesn't make any difference which method you use.

  Your idea, and conclusions, of running the patch thru the bore at different time intervals with smokeless is something I haven't tried. So.... something to try also. With BP a lot depends on the humidity level. Above 50% you can push a dry patch thru most any time and it'll go thru easy. When the humidity gets down around 30% it works best if you wait a while. If you try right away you have to pound the patch thru. Of course if you blow tube it goes easy.

  Like your drop tube conversion idea. I've noticed these grains of powder clinging to the case neck. I mostly use 4227. Mostly with me is that I see this right at the mouth of the case. Possibly because I haven't really looked down inside to see if powder clings there. I don't use a wad down near the powder either so this idea will go on my "to do" list for sure.

  Boy! Does temp. ever affect powder burn rate. I had this driven home when I had a real good load for shooting Sporting Clays. When real cold weather came that load would fizzle, hang fire, or not go off at all. Had to add 2 grs. of powder to get it to the point where it could sustain a burn when ignited. Maybe a hotter primer would have had the same effect.

PETE