Thread: 6.5 Creedmoor load development

Got out to the range today and set up for some more test loads. I had to shoot from 110yds as my 100yd prone location was a mud pit after the rain.

I loaded up a few rounds of the 143gr ELDX in Lapua brass and also twice fired Peterson brass with 41.5gr of ADI 2209 and seated them to my pre chamber mod COAL of 2.754" this gave a massive jump to the lands but Im really just looking at pressure not accuracy. I also loaded 5 with the same charge and seated them to fit my mag wich gave 15 thou jump to the lands, this is to see if the velocity and pressure dropped off and see if accuracy got better.






This is 5 shots of the Lapua 136gr Scenar in Lapua brass with RL16 powder.
The first cold bore shot of the day with a clean barrel (boretech eliminator) was the low one in the group and showed a lower velocity of
2862fps then 2895fps, 2898fps, 2893fps & 2900fps. Even with the low shot it is a 1/2 MOA group at 110yds. The brass shows nothing remotely exciting going on.





The next was 5 rounds is my other pet load of 130gr Sierra tipped match kings in Lapua brass with RL16 powder.

2946fps, 2938fps, 2951fps, 2946fps, 2942fps

Another boring sub 1/2 MOA group. Those are my control groups in which I hope to demonstrate the rifle shoots and my hand loads are consistent. The brass also shows no signs of high pressure.



Now for the 2209 that gave me so many problems at the start...
First up the exact same load with deep seated ELDX that I noted as too hot and sticky bolt in my notes. One thing to note is my old data was with the 24" barrel shooting an average of 2730fps but the extreme spread was terrible. It is now at 20" so the drop in velocity was expected.

2606fps, 2626fps, 2651fps, 2625fps, 2631fps

The brass showed the same high pressure ejector marks as before and the bolt had notable friction on the lift. The group was about 1.4"ctc which is by far the worst group Ive shot in this rifle, to be fair the drop in velocity probably can be blamed for that as they still shot under an inch in my first tests.







No this is where I got a bit negligent and put the same load and deep seated ELDX into a Peterson case knowing that these cases show higher pressure than the lapua have with the same charge and bullet.

You will see I chickened out after 3 rounds but you get the gist of what the results were..

2590fps, 2562fps, 2587fps

Notice the additional drop in velocity as my fancy match brass takes the hit instead of the projectile..








A this point my barrel and suppressor were heating up and it was starting to rain, I pressed on and sent 5 rounds of the same 2209 load in lapua brass only this time pull out to mag length and 15 thou off my new lands..

2641fps, 2649fps, 2636fps, 2652fps, 2544fps,



Now here's where it gets interesting, no sticky bolt lift and only very minor ejector ring scuffs that are hard to see in these pics but it circles the 6 on the stamping. But take a look at the primers.. this is the flattest I've seen a BR-4 primer, it is flat to the point where it is no longer round and material has flowed to the edges to form a mushroom like burr that you can catch a fingernail on when dragged over it. The firing pin cratering is also bad with sharp jagged edges. All 5 of these primers are in worse shape than the last 3 Peterson ones yet the brass only shows very minor wiping.





Id love to hear some others on this one. Why is IMR AR2209 aka H4350 behaving so badly in my rifle yet it is the go to powder for 90% of other 6.5 Creedmoor shooters?

The only thing Im yet to rule out is a bad batch of powder. Its only a couple of years old and smells as it should but I guess I cant rule that out unless I try another batch.

A look back at have documented in my initial range testing notes says this:

143gr ELDX with 41.5gr of 2209 AV of 2726fps with 49fps ES and a group of .832" ctc "too hot, heavy bolt lift"

139gr Scenars with 41.5gr of 2209 AV of 2734fps with 11fps ES and a group of .791" ctc "light pressure signs"

130gr Sierra TMK with 42gr of 2209 AV of 2766fps with 8fps ES and a group of .710" ctc "light pressure signs"