That Sweet-Spot...

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Howdy all,

I have a question that goes out to anyone and everyone that fills a case with powder
and caps it with a bullet.

How and or what method/process do you use to find that 'sweet-spot' in terms of
loads for your rifle ?

What steps do you guys go thru, what signs/signals do you look for and what do you
use as criteria for determining the 'winner' ?

I've been loading for a number of years now but I thought about this about a week ago and
it's stuck with me and curiosity has won me over.
 
I'm new to reloading but here is what I've done, based on what I've read in books and online.
I use http://www.hodgdonreloading.com/data/pistol as well as a couple loading books for my info, and for my 9mm, 124 gr I loaded 10 rounds of 3.8, 3.9 and 4.0 grs of Hodgdon Titegroup and will see what works the best. Then I will fine tune what works best to the 1/10th grs for accuracy. If 3.8 is good I will lower the charge towards the starting point of 3.6 grs.
From what I've read, only load about 10 rounds of each so you don't waste powder (and barrel) on charges too hot and take your time to tailor make the charge needed for your gun.
Best,
Gary
 
I'm not a real benchrest shooter and I'm not a long range hunter. I target shoot for fun at 100, 200, and sometimes 300yds and I found the following method to work well.

Load 5 rounds from start load to max load in 1gr increments.
Shoot them, record groups.
Take the 1-2 best groups (pretty much always two groups beside each other in the scale for me) and load more starting 0.5gr below the and stopping 0.5gr above in 0.5gr increments.
Shoot them, record groups.

Usually this will give me a great shooting load. It is often near the start load and as a result almost always a 200-500fps lower than the max rated velocity for a bullet weight in a given cartridge. For example my 308 load is pushing a 150gr bullet at only 2450fps where as max loads are usually around 2800fps. I have shot .875" groups at 200yds though so I wont complain.

There are other methods including ladder tests, loading for max rated velocity and then trying to get the accuracy later by adjusting OAL, and various others. This is just the one I use and it has served me well so far.
 
Dan Newberry OCW then play with seating depth to tighten groups. The "Sweet Spot" is the OCW. Optimum charge weight. It is the most forgiving node. Audette ladders are so passe'. There are no shortcuts. Pick a quality bullet. Slowest burning powder getting info from several books. Use the OCW method at 100m. Then adjust seating depth and shoot 5 shot strings at 300m. If you have 4 seating depths you are trying shoot #1 the #2 then #3 and repeat not 11111 22222 33333 same as newberry explains for OCW. Make sure your newly rolled rounds fit the mag and cycle before leaving home to save embarrassment and time. To find max seating depth (Lands) I cut the neck of a case lengthways with a dremel. Start a bullet. Close bolt. Carefully open bolt. Measure and repeat at least 5 times. You can buy tools to do this but Im cheap.
 
My first step is to reference my reloading manuals........my favorite, the Nosler and Sierra, and in that order. I then research their most accurate powder load, starting midway and then working in one grain increments until max. I make 6 cartridges of each powder load and usually end-up with 24 rounds with that particular powder. I then repeat the same process with two other powders that I have researched from other users who had great accuracy. In total I usually have 72 cartridges loaded from three different powders.

Range time:
Fire three shots from clean bore and let cool
Fire three shot from fouled bore
Clean barrel and then go to next powder increment
Repeat procedure
The sweat spot is usually not achieved on the first trip to the range, usually found on the second trip, then perfected (sweet spot) on the third trip.
Keep it simple, choose one bullet that you wish to use and then work around it with three or four different powders.
 
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