I never made it to the range today because of the weather and brass delemas.

I weighed cases from two boxes of once fired factory brass. The results are less that exciting.

The cases weighed from 275.1gr to 279.4gr. The boxes were not from the same lot but weighed in the same range so I decided to weigh them all full of water and see if this weight corralated with its case weight.

Cases with water weighed from 391.6gr to 394.9gr and did indeed corralate to within a tenth grain or two of the expected weight accross the whole board.

Here's my delema. I only have this brass to load so far and I cant even get twenty cases within 1gr and worse it's almost a full two grain spread.

Question is, if I use these cases and load up one round each in .2gr increments from starting load to max load to see where the sweet spot is, do I start with the highest case volume and the lowest charge wt together and end up with the lowest case volume and highest charge wt together thus increasing pressure a little faster than if I combined them in the opposite way that would in effect almost cancel each other out?

I realize that some may feel this is splitting hairs, but it will have an effect and skew the results if not accounted for especially while looking for consistant grouping over a range like this.

I usually develope a load like this with case and bullet weights within .5grs and just note the weight range used for later adjustments if anything weighs different and accuracy isn't there anymore.

At this point a couple hundred rounds of brass would be the answer but I don't have any yet.

To those that weigh your brass for the ultra, what are you experiences and practices?

[ 11-07-2002, 07:57: Message edited by: Brent Moffitt ]

The brass I use does vary by a few grains but the load I am using provides 1/2" groups.I can increase or decrease the powder charge by a grain each way and the group size does not change so my load is very stable in my rifle.I will not use a load if changing the load by a few tenths of a grain opens up the groups as such loads often behave the same way with changes in temperature.

You know, I have tried this a few times. It made almost no difference in my 300RUM brass. My groups didn't improve much if any. But what I should have been more concerned about was not knocking the shoulder back and crooking the necks with the expander ball.

I don't put much faith in magizines, but this months issue of Handloader shows comparisons of brass that has been deburred, wieghted and the whole bit compared to brass that didn't have all that attention. There wasn't much difference in the groups. But in the same mag, they have an article about mixed headstamps and the groups were all over the place. So who knows.

Well I have good news, but I can't explain it though. The cases I weighed spanned 4 grains. If you go back and read my previous post I said the cases with water spanned 4 grains also. I looked at it totally ass backwards, probably because I expected the results to be what everyone might think, all the lighter cases would have more internal capacity, right? Wrong.. the cases that were 4 grains lighter were still 4 grains lighter with water, meaning that internal capacity was EXACTLY equal! Each case was lighter by the same amount with water as the case weight itself indicated. Am I making sense? It wasn't the other way around. The average water weight itself was 115.7gr. Maybe some of you guys can check yours too and see how consistant accross the board this 300 ultra brass is. Mine was filled to the top with water in an eye dropper with a drop of dish soap mixed in to break the surface tension, no bubble on top, just flush with the mouth. They fireformed once and had fired primers in them at 2.840".
Boyd, this explains why you find no difference at 1000 yards. And we all frowned on the Remington brass. I am totally amazed to say the least. I might add that this was two boxes of brass from different lots too!

This may be an end to my weighing cases if this proves to be true the next few times I check some. These cases were all within +or- 3 tenths of a grain in internal capacity on cases that had a 4gr spread, WOW!

I thought you all would appreciate hearing this.