6.5 Creedmoor - 147 ELD-M H4350 SRP Loads

[MMH]

Just starting to load 6.5 Creedmoor. Picked up (500) 147 gr. ELD-M bullets & 3 lbs. of H4350. Will be using Alpha SRP brass. This will be shot out of a Masterpiece Arms rifle w/ a 26" barrel for PRS shooting out to 1000 yards. Seems like most people end up between 41 to 42 grains & 0.020 bullet jump.

Hodgdon lists 36.7 gr. as a starting load & a max load of 41.8 gr. Don't want to go too hot (save the barrel) as at 1000 yards & will be comfortably supersonic.

First of all, this is a new rifle. How many rounds should I run through it before starting load development? I'm thinking that by 30 rounds or so the barrel should be ready.

To develop the loads I will start at 40 grains & go up in 0.2 gr. increments up to 42.0 grains. I will load w/ a 0.020" jump & load 3 rounds per charge. I will chrono the rounds (Labradar) & shoot groups at the same time. Will base my decision weighing in group size and velocity spread. At that point I will seat at .015" & 0.25" to see what shoots better.

Comments on my plan?

 

[John Glidewell]

There is a sticky on 6.5 cm loads. you can also use the search function - this question is asked multiple times a week

 

[Lightning8]

1. You will probably need more than 30 rounds before barrel speeds up. Probably 100+.
2. Amazing amount of "known good loads" for 65CM, 147s, and H4350 - as stated above see the 65CM load sticky.
3. If shooting PRS - trend is heavy 65CM projectiles at moderate speed to minimize recoil and improve seeing impacts.

 

[eamars]

With 42.5gr AR2209 (H4350), I'm getting ~2774fps from 24" barrel and 2900fps from 30" barrel.
The pressure sign is still minimal.

 

[MMH]

1. You will probably need more than 30 rounds before barrel speeds up. Probably 100+.
2. Amazing amount of "known good loads" for 65CM, 147s, and H4350 - as stated above see the 65CM load sticky.
3. If shooting PRS - trend is heavy 65CM projectiles at moderate speed to minimize recoil and improve seeing impacts.

Agreed. Do not expect barrel speed to stabilize until at least 200 rounds. Figure I can tweak the load at that point. Just want to be able to get some use & practice out of the rifle and not wait until barrel fully broken in. Will definitely stick to the heavier bullets - 147 and up.

Any comments on looking for accuracy and velocity stability at the same time & shooting only three rounds?

 

[Lightning8]

Any comments on looking for accuracy and velocity stability at the same time & shooting only three rounds?

Lots of threads here on load development. Hornady podcasts stirred conversation with their "your sample size is not big enough".

I pick a known good load that is safe (falls within major reloading data range) for first 125 or so rounds while the barrel is speeding up.

After 125 shots or so, I use abbreviated technique. I pick a speed range I want based on known "good load" data. Then I shoot one round each at different powder weights to find the bullet/powder/primer/rifle combo that gets me in that speed range. I pick a couple of powder weights from there and shoot a couple of 5 shot groups. Typically, that gets me right back to a known "good load" when loading for a known, established PRS cartridge.

There are many that will advocate for a more detailed, complicated approach but will also end up at an already established load.

 

[Dog Doc]

I consider myself fairly new but try to research more than post. My technique is old school and new school, but it works for me at least with 3 rifles so far. My rifle is different than yours and work up is always necessary in my opinion. So, using your same powder and bullet (H4350/147 ELDM).
1st step: Velocity testing paired with a 300 yard ladder. 41.0-42.0 in 0.2gr increments. I do 3 and average the results totaling 18 rounds.
2nd step: Take selected charge you want to use and do seating depth testing. Depending on jumps you want to test this could be 15-35 rounds.

My hope from step 1 is to find a velocity with minimal change in the average of 3 charges, then pick the middle one. I also hope to see minimal vertical dispersion on the ladder. If those 2 line up, this is the charge I am using. If they do not, then it gets confusing, lol! But you should get the idea.