Question on burn rates

[Howa 9700]

BTW, when looking for what would be a "full case" of powder, i found out early on that what appears in the manuals and what happens inside your individual case using your powder lot and your bullet seating depth.....are two different things. First clue was when I tried weighing the amount of powder I got from the Lee dippers vs. what is shown in tables for same. Some powders were similar.....most were not even close.

So what I came up with was a device of my own creation...........I would take a sized, ready to load empty case, seat the bullet in question to whatever OAL i would be using........then drilled out the primer cup such that I was able to backfill the case under the seated bullet until case was filled to overflowing. Then weigh that and I have weight of a 100% full case. I do that for every powder I try......at least for all the rifle calibers I'm loading for.

Have not done that for pistols, but beginning to think it may be a good idea, as it will give me some idea as to what a full to compressed powder charge would be. It could be that out of the dozens and dozens of powders used in 9mm, a best one might be one that gives you a full to lightly compressed powder charge at the seating depth used........dictated by choice or max OAL.

 

[GeoDudeFlorida]

My dad always talked about case fill around the bench for good consistency.... I'm sold on the idea, but also on the form factor. When world records, king of the 2 or 3 mile or any national level matches start being won with ball powder I'll take heed. It's coming some day but I have yet to see it. I'm also sure a funny car is being built with an electronic package over methanol.

Been done.

 

[Thomasss]

Maybe I'm reading between the lines too much, but a168 gr. 30 cal is generally a match bullet where 180 and 150's could be hunting bullets that just don't have the same accuracy potential.

In general this info is true, but I've found many exceptions.

It is when you start loading bullets lighter than about 150 gr or heavier than 180 gr that you will start seeing significant gains in performance with a different powder.

Not with my gun. Don't mean to argue but my best shots have been with 150 grain to 168 grain. Again, all guns are different and one must find what works with your gun.

Pick 1 powder and 1 bullets to work up. Do a standard powder charge work up. Find the most accurate node. Then you can play with the OAL and see if you can improve accuracy. Unfortunately there is no easy answer to your question. You will need to put the work in to find a good hunting load in YOUR rifle.

The pink picture is 165 grain Hornady BTSP @2803 ave. fps @100 yards with the bullets seated at 3.257 with my 1970 Rem. 700 in 30.06. The groups are between .5 & .6 MOA. ( I was correcting for windage at the time.) The black target shows two groups. Both groups were shot exactly the same loads except the larger group used Enduron 4451 and the smaller group used IMR-4350. The powders were measured for 2750 fps.


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