There are many ways to complete your load development, this is one that I have used several times with success. I wont claim to have created this method as it is a combination of several very experience shooters. I will also copy some links to helpful resources below. This is meant to be a basic overview and not a comprehensive reloading manual. Always reference a reloading manual and work up your loads safely.
Step 1: Pick one bullet, primer and powder combination to focus on. Choose a bullet appropriate for your twist, case and chamber. If unsure, consult your gunsmith.
Step 2: Find your "lands". Now this is a controversial topic and I wont drill down to deep on it because I simply dont care and it wont affect the result. There are lots of ways to find your lands, however they will slowly move on you and the actual engagement doesnt matter as PRS and Practical Precision shooters dont shoot jam. I utilize either a Hornady OAL gauge (when available) and test and measure 5 times with 3 different bullets and average my COAL for a start point. If the caliber I am working with does not have a Hornady gauge, I make a dummy round too long for my chamber, remove my firing pin/spring assembly and begin trying to gently chamber my cartridge. I feel for the bullet engagement and will continue seating my bullet .005 deeper into the case until my bolt handle drops freely. This is my "lands" for a starting measurement.
Step 3: I begin all my testing at .020 off my "lands" measurement. I am using "lands" as it may be off by a few thousandths, but again, it wont matter, I am just ensuring my bullets are not jammed when I begin and creating a data point.
Step 4: Utilizing either a reloading manual or a good data spread of internet information for a cartridge, I will find a good median charge weight. If no manual available, I will find 20-30 loads on a popular forum and chart them in Excel and find the re-occurring charge weight and call that median and start lower.
Step 5: Find your Optimal Charge Weight (OCW). There are a few ways to find this, however I like to get to it as fast as possible with as little range trips as possible. Many folks recommend shooting a ladder test at distance. This can induce environmental influence as well as low statistical reliance if only shooting one round of each charge. To combat and simplify this while still reducing my overall required shots to complete, I utilize a 3 round, 10-12 charge OCW ladder test at 100-200m. For mid size cases such as the Creedmoors and 308, I work up in 0.2gr increments, for small cases like the BR's, Dashers and GT, I reduce the charge graduation to 0.1gr. For large magnums such as the 300PRC or 338 Lapua, it is easy to jump in 0.3-0.5gr increments and Cheytac based cases 1gr increments.
Example: 6.5 Creedmoor, 139 Grain Scenar, CCI 450, starting at 2.800 (no chamber measurement)
42 grains is a very common load of H4350, Looking at this as a "middle", I want to shoot 10-12 groups. I want to move in 0.2 grain increments.
3rds - 40.6 gr Utilizing these charge weights, I will go the range and shoot all for 3 rd groups over a chronograph
3rds - 40.8gr and record the results. I am not looking for tiny groups yet, although they may be evident. I am looking
3rds - 41 gr for 2-3 charge weights that the velocity "flattens" or shows the least change per charge. The reason we
3rds - 41.2gr load and shoot 3 per charge, is to provide better statistical data on each charge. Ie; If charge 1 was high
3rds - 41.4 gr on the velocity spread, but shot 2 was low on the velocity spread, this could falsely appear as if the two
3rds - 41.6gr charges had "flattened" out. Shooting three will give you an ES per charge as well as a median velocity.
3rds - 41.8 gr Utilize the median velocity to graph your results. (Link to Excel spreadsheet below)
3rds - 42gr
3rds - 42.2gr
3rds - 42.4gr
3rds - 42.6gr
3rds - 42.8gr
3rds - 43gr
Step 6: Record and input all the velocities into the 6.5 Guys Load Analysis Worksheet (Amazing Tool!) Link below. This will provide you ES/SD/Median and graph all your data.
Step 7: Look for the flat spots in velocity, this is where the accuracy node is, even if it didnt shoot a good group initially. Choose the middle charge weight and if the groups are good, go re-confirm at the range. If the groups are not what you want, it is time for seating depth tuning.
Step 8: Seating depth tuning. Both Erik Cortina and Berger have excellent procedures to assist in tuning seating depth and I recommend watching Eriks Youtube Videos (link below). But basically starting at the .020 jump you measured, start loading 3 round groups going shorter (longer jump) in .003 increments. Shoot these groups until 2-3 groups present acceptable group sizes. This is the jump node. From here, choose the longest seating depth in that node and get out shooting! This method reduces the "chasing the lands" that happens when guys find jump sensitive loads.
Step 9: Post up pictures of your tiny groups on the EM Precision facebook page!!
6.5 Guys Load Analysis Worksheet and Tutorial
http://www.65guys.com/load-development-analysis/
Erik Cortina YouTube
Seating Depth
https://youtu.be/a7vjgEgnhHk
Stop Neck Sizing
https://youtu.be/lLG2kSrD40g
Chasing the Lands is Stupid
https://youtu.be/oRXlCG9YZbQ
Step 1: Pick one bullet, primer and powder combination to focus on. Choose a bullet appropriate for your twist, case and chamber. If unsure, consult your gunsmith.
Step 2: Find your "lands". Now this is a controversial topic and I wont drill down to deep on it because I simply dont care and it wont affect the result. There are lots of ways to find your lands, however they will slowly move on you and the actual engagement doesnt matter as PRS and Practical Precision shooters dont shoot jam. I utilize either a Hornady OAL gauge (when available) and test and measure 5 times with 3 different bullets and average my COAL for a start point. If the caliber I am working with does not have a Hornady gauge, I make a dummy round too long for my chamber, remove my firing pin/spring assembly and begin trying to gently chamber my cartridge. I feel for the bullet engagement and will continue seating my bullet .005 deeper into the case until my bolt handle drops freely. This is my "lands" for a starting measurement.
Step 3: I begin all my testing at .020 off my "lands" measurement. I am using "lands" as it may be off by a few thousandths, but again, it wont matter, I am just ensuring my bullets are not jammed when I begin and creating a data point.
Step 4: Utilizing either a reloading manual or a good data spread of internet information for a cartridge, I will find a good median charge weight. If no manual available, I will find 20-30 loads on a popular forum and chart them in Excel and find the re-occurring charge weight and call that median and start lower.
Step 5: Find your Optimal Charge Weight (OCW). There are a few ways to find this, however I like to get to it as fast as possible with as little range trips as possible. Many folks recommend shooting a ladder test at distance. This can induce environmental influence as well as low statistical reliance if only shooting one round of each charge. To combat and simplify this while still reducing my overall required shots to complete, I utilize a 3 round, 10-12 charge OCW ladder test at 100-200m. For mid size cases such as the Creedmoors and 308, I work up in 0.2gr increments, for small cases like the BR's, Dashers and GT, I reduce the charge graduation to 0.1gr. For large magnums such as the 300PRC or 338 Lapua, it is easy to jump in 0.3-0.5gr increments and Cheytac based cases 1gr increments.
Example: 6.5 Creedmoor, 139 Grain Scenar, CCI 450, starting at 2.800 (no chamber measurement)
42 grains is a very common load of H4350, Looking at this as a "middle", I want to shoot 10-12 groups. I want to move in 0.2 grain increments.
3rds - 40.6 gr Utilizing these charge weights, I will go the range and shoot all for 3 rd groups over a chronograph
3rds - 40.8gr and record the results. I am not looking for tiny groups yet, although they may be evident. I am looking
3rds - 41 gr for 2-3 charge weights that the velocity "flattens" or shows the least change per charge. The reason we
3rds - 41.2gr load and shoot 3 per charge, is to provide better statistical data on each charge. Ie; If charge 1 was high
3rds - 41.4 gr on the velocity spread, but shot 2 was low on the velocity spread, this could falsely appear as if the two
3rds - 41.6gr charges had "flattened" out. Shooting three will give you an ES per charge as well as a median velocity.
3rds - 41.8 gr Utilize the median velocity to graph your results. (Link to Excel spreadsheet below)
3rds - 42gr
3rds - 42.2gr
3rds - 42.4gr
3rds - 42.6gr
3rds - 42.8gr
3rds - 43gr
Step 6: Record and input all the velocities into the 6.5 Guys Load Analysis Worksheet (Amazing Tool!) Link below. This will provide you ES/SD/Median and graph all your data.
Step 7: Look for the flat spots in velocity, this is where the accuracy node is, even if it didnt shoot a good group initially. Choose the middle charge weight and if the groups are good, go re-confirm at the range. If the groups are not what you want, it is time for seating depth tuning.
Step 8: Seating depth tuning. Both Erik Cortina and Berger have excellent procedures to assist in tuning seating depth and I recommend watching Eriks Youtube Videos (link below). But basically starting at the .020 jump you measured, start loading 3 round groups going shorter (longer jump) in .003 increments. Shoot these groups until 2-3 groups present acceptable group sizes. This is the jump node. From here, choose the longest seating depth in that node and get out shooting! This method reduces the "chasing the lands" that happens when guys find jump sensitive loads.
Step 9: Post up pictures of your tiny groups on the EM Precision facebook page!!
6.5 Guys Load Analysis Worksheet and Tutorial
http://www.65guys.com/load-development-analysis/
Erik Cortina YouTube
Seating Depth
https://youtu.be/a7vjgEgnhHk
Stop Neck Sizing
https://youtu.be/lLG2kSrD40g
Chasing the Lands is Stupid
https://youtu.be/oRXlCG9YZbQ