Thread: 10 Shot Load Development

I had a go at using this method today with my 6.5 Creedmeme.

Components: 147gr ELD-M, once fired Lapua brass, 2209 and lit with CCI450's.

Sized with a Redding FL bushing die, using a Wilson .288 bushing, with my brass this gives neck tension measuring .289-290. Seated to 2.8" OAL with a Redding competition seater.

Oh and rifle, Bergara HMR

I loaded 10 shots and chronied them -

39.0gr - 2411fps
39.2gr - 2446fps
39.4gr - 2455fps
39.6gr - 2473fps
39.8gr - 2482fps
40.0gr - 2496fps
40.2gr - 2506fps
40.6gr -2520fps
40.8gr -2520fps
41.0gr -2530fps

I thought it was interesting that there was a near linear increase in muzzle velocity for 39.2gr up. 40.8 appeared to be in the middle of a plateau, which is what I was looking for.

I didn't shoot at paper while doing this, just shot rounds over the chrony into the berm. I only wanted to see a plateau in velocity.

Back at the bench I fired up my Lyman powder dispenser and set it to 40.8gr, and loaded up another 15 rounds. It usually gives me a variation of .1-.2 gr either side of the target weight if I just let it do it's thing and don't re-weigh. Some of the charges were spot on 40.8 gr, but others were 40.7, 40.9, 41.0.

With the last few minutes of daylight I was unable to chrony the loads, but I got pretty reasonable results on paper at 100m.



Bottom group is the last shot, with more care, and POI adjusted .1 mil down and the same left. All loads were selected at random. Now to see how they do over the chrony. It seems like a good way to save components and time with a new gun. I could probably tighten those groups by playing with seating, or working up further and looking for another plateau, but if it looks good SD wise I might just run it.

Anyone else do it this way?

Pic is on the piss

Oddly, pic is correct on my phone, and 90 to left on PC.

Hey Beavis, great report. I have done it when i swap from Hornady to Lapua brass and work the treat. this process is better understand if shot a further distance to also check the POI variation, but, the way you done will work also. You got it right at the velocity variation, when you find the so called "flat spot" you get it in the very "middle" and work from there, at least it was what work for me, once you sort it out then the seating depth is a tune in point.
I am not an specialist by any means but keen to help if i can.

Good luck!

Mac

Result achieved from this method…



Sorry but the photos looks like have been drinking all together…

Got to be happy with that....now if you stop shaking it would tighten up even more....

Simlar, but I shot everything over a chrony and three or four shot groups at the same time.
I'd load around 40.8 depending on pressure signs.

Suggestion!!! As you shooting 147gr projectiles have you thought about a slower powder? As stated in the very beginning, it s a suggestion and it is based on few friends shooting the lighter 140gr at faster velocities than the 2209 or 4350... being your projectile heavier it may be an option to look at.

Keep the good work and get out and shoot!

Originally Posted by PERRISCICABA

Suggestion!!! As you shooting 147gr projectiles have you thought about a slower powder? As stated in the very beginning, it s a suggestion and it is based on few friends shooting the lighter 140gr at faster velocities than the 2209 or 4350... being your projectile heavier it may be an option to look at.

Keep the good work and get out and shoot!

I have just been looking at Reloader 16. Sounds like it has become a go to powder for this cartridge. I might buy a bottle when my 2209 is burnt up.

Interestingly, my above load is clocking marginally faster than my previous load - 41.5gr under a 140gr A max. The 147 has a pretty wicked BC, so I am not too worried about it being speed demon.

Originally Posted by Beavis

I have just been looking at Reloader 16. Sounds like it has become a go to powder for this cartridge. I might buy a bottle when my 2209 is burnt up.

Interestingly, my above load is clocking marginally faster than my previous load - 41.5gr under a 140gr A max. The 147 has a pretty wicked BC, so I am not too worried about it being speed demon.

The thing with RL16 is “I” think it is a unicorn at the moment, have t hear of it yet in my “neck of woods”, will be interesting and challenge to keep the supply “I” think.

Originally Posted by PERRISCICABA

The thing with RL16 is “I” think it is a unicorn at the moment, have t hear of it yet in my “neck of woods”, will be interesting and challenge to keep the supply “I” think.

Talk to Kiwi Greg, he could have some.

Sent from my SM-A530F using Tapatalk

Good stuff, similar to how my brother and I do our load development now. No point loadin 3 up at low charge weights when you won’t accept their low velocity anyway....

Similar to how I do it. I do five for pressure signs at about 1% increments. Then load 4-5 lots of 3 at smaller% increments and chrony then onto paper with coloured tips and a long rest between shots @300m. I start from lowest to highest load, then highest to lowest, lowest to highest.
I then plot vertical dispersal and compare it to standard deviation of velocities of that charge weight.
I look for the load with the least vertical dispersion with the most consistent velocity.

I'm way too OCD though, and it's a massive chore.

Originally Posted by PERRISCICABA

Hey Beavis, great report. I have done it when i swap from Hornady to Lapua brass and work the treat. this process is better understand if shot a further distance to also check the POI variation, but, the way you done will work also. You got it right at the velocity variation, when you find the so called "flat spot" you get it in the very "middle" and work from there, at least it was what work for me, once you sort it out then the seating depth is a tune in point.
I am not an specialist by any means but keen to help if i can.

Good luck!

Mac

Result achieved from this method…

Attachment 89905

Sorry but the photos looks like have been drinking all together…

Sent from my WAS-LX2 using Tapatalk

Could also be worth trying Norma URP. I'm running it in my 6.5CM with the 147gr ELD-M's, very accurate and low ES & SD

Sent from my SM-N950F using Tapatalk

this is exactly the way i have been doing it, i usually graph them at the bench by hand and then i usually find 2 plateaus, a lower one and one right up near where it starts showing pressure, i usually just choose the flattest one of the 2 and then load in the middle, it has been working well for me.

I have a second press that fits into the towbar of my ute and i take my Lyman gen 5 to the range as well running it off the inverter, this way i can do it all is 1 range trip.

I usually have a load in 10 rounds or less, then i load a few to test it at 100 and maybe 3 - 500 so i would say max 20 rds and i have a solid load.

I wish I had tried this years ago to be honest. The old load up 5 shots in .3-.5gr increments and shoot 5 shot groups up to max is a really punishing time consuming and component burning method.