Powder selection & Ladder load testing ?'s

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boatbum101

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For selecting powders is it best to see what gives top velocity for a given weight bullet & selecting it & rest that are within 100fps of the top ?
For a medium capacity rifle cartridge start at beginning load & work up in .5gr increments to the max while carefully observing for high pressure signs ?
Use same piece of plain white backer with same aiming point & shoot 3 rounds starting with lowest charge ? Where different charges have a mean POI this indicates accuracy node for this bullet / powder combination ?
Once the above is established reshoot same test on a clean backer with the loads found in the accuracy node found in round 1 ?
Tightest group in round 2 will be best load for this particular combination ?
After all this retest with different seating depths to determine where this bullet shoots best ?
Then once best OAL is determined reshoot with different neck tension to see what bullet pull works best ?
Once all that's been determined . Try different primers to see if it affects group size & doesn't give pressure signs ?
I guess you only want to change 1 variable at a time to evaluate its effect ?
 
Way to much/many questions. Start your quest at 6.5 Guys. They have enlisted Scott Satterlee to come up with a 10 round load development. Their is one big caveat. You must be a very proficient hand loader for this to work. It was developed by Scott who they mention in the video is a single digit extreme spread loader. I am starting to achieve single digit standard deviations. Also the use of a good chronograph is a must. They actually mention the Magnetospeed. Once their initial development is done they move long range for group testing.
If you don't have a chrono then a 200-300 yard range can be used for load development. You would perhaps use something like this.
Now there will be some controversy but reading pressure signs is not a cut and dried subject. Some believe you can be in dangerous pressure areas with no signs. My Savage bolt actions (both) have slightly cratered the primer since new with factory and hand loads. It is probably indicative of an slightly oversized firing pin channel. Other signs of pressure can be hard to spot. A simple google will teach/confuse you all you need. You also need to tell what type of shooting, what rifle, and what expectations you have. Fill in what type of loading experience you have. Ask specific questions and one at a time. Use the search function on this site and google.
Now I'll start with your first question. I look for velocity/accuracy nodes. I use the Hodgdon site and see the recommended powders for the bullet and weight. I do use a Magnetospeed to find loadings that have a velocity flat spot. I have never found one .8 grains wide like the video, but I have found .3-.4 grain nodes where the velocity is level. This gives some leeway while loading and reduces the vertical group component at long range. After finding the highest velocity node, I load 5 shot tests varying the seating depth. Always measure to ogive not overall length to check seating depth. Now you have a base load that you can start using to test other things. Time to go longer range. Changing primers or powder may require you to start over at the beginning.
 
Yes I have an Oehler 35P chrono . I use Redding bushing dies w/o the expander & micrometer seater . Expand with Redding mandrel die , decap with a universal decapper. I also use Lapua or Norma cases as it cuts down brass prep time . It's a hunting rifle with factory Sako hammer forged so I don't have to neck turn . I believe that 300yds will suit my purpose because frankly with this caliber I will restrict my shots to that or less . If I shoot longer distances I want more horsepower on tap . I know about pressure signs & also mic case heads . Years ago wildcatting one did not have pressure tested load data in many cartridges like 30-378 , 7mm & 6.5 - 06 and AI cartridges that some have become factory fodder now . FWIW rifle is a Tikka T3 that I installed a OS steel recoil lug , pillar & Devcon bedded with free floated 570mm barrel & recess crowned also .
 
For 300 yard hunting Most everything I said is excessive. I would think 100 yard groups would be enough. I load as if I were shooting 1000 yards, but my long range range is only 600 yards and steel only. Most hunters are fine with 1" at 100 yards. Out to 300 yards there could be only an inch difference between a 308 at 2900fps and at 2800 fps.
 
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