Consistent ES and SD

[OFFISHN]

I have been reloading for many years and struggle with consistently achieving single digit ES and SD. I use a lab radar with the magnetic trigger and rarely not capture a shot. My reloading practices is good brass (lapua) CCI primers 200 or 250 depending on the caliber (6.5 creedmoor or 6.5 PRC) Hornady 140 ELDM or 143 ELDX, each rifle is a custom action and better then average barrels (proof on the PRC and Benchmark on the creedmoor). All though each rifle has produced .250 or better groups if I do my part I struggle with single digit ES and SD. Typical powders I have tried are IMR OR Hodgons H's or Retumbo. I use a FL dies and bump brass back 2-3 thousands. I use a carbide mandrel to set neck tension at 2 thousandths. I clean and brush inside necks after resizing. I typically set my jump at 40-50 thousandths to start and tune as needed. My powder scale is the Creedmoor digital and I calibrate and weigh to the kernel.

What am I missing? Is it my components or am I missing some important step. Oh I anneal every 3 firings.

 

[BillNye]

The two things I would try next would be moving to annealing every firing after cleaning but before sizing and using a dry neck lube, graphite or h-BN. I would also consider swapping to a beam scale or upgrading to A&D FX120i or similar. Poor ES is usually neck tension related or powder charge related and there's lots that can cause a digital scale to wander

 

[OFFISHN]

Thanks. I do have a beam scale I can and have verified on every once in a while. I calibrate my scale after warm up every time even thou it's in a temp controlled room constantly. I'll give the dry neck lube a try. Are you just dipping your bullets in lightly before seating? Or just making sure to get a good coverage on.

 

[Pdyson]

With great groups like that I wouldn't worry too much about it. For me the larger the case capacity the harder it is to get low SD ES numbers. My sizing process similar to yours however i like to use only Match and Magnum Match small and large rifle primers. I anneal first, pin wash, and just recently started coating the inside of my case necks with NEOLUBE#2 (graphite lube in a quick dry solvent). I was just looking over my notes from my last range trip to work up a new hog/ Coyote load for my 6.5 Grendel. Anyway I ladder tested 8208XBR, CFE223, 2520, and LeverEvolution. Of all those strings, I only had 2 strings with an SD higher than 9 and both were using the LeverEvo powder. Those SDs were 10 and 12 and the groups were horrible. I'd like to say the neolube helped but I'd have to do more testing with and without to be sure. Match primers can Definitely help.

 

[OFFISHN]

With great groups like that I wouldn't worry too much about it. For me the larger the case capacity the harder it is to get low SD ES numbers. My sizing process similar to yours however i like to use only Match and Magnum Match small and large rifle primers. I anneal first, pin wash, and just recently started coating the inside of my case necks with NEOLUBE#2 (graphite lube in a quick dry solvent). I was just looking over my notes from my last range trip to work up a new hog/ Coyote load for my 6.5 Grendel. Anyway I ladder tested 8208XBR, CFE223, 2520, and LeverEvolution. Of all those strings, I only had 2 strings with an SD higher than 9 and both were using the LeverEvo powder. Those SDs were 10 and 12 and the groups were horrible. I'd like to say the neolube helped but I'd have to do more testing with and without to be sure. Match primers can Definitely help.

Thanks. I'll try and find some of those primers to test. I'll look into those powders as well and start using a dry lube for bullet seating. I open to just about everything to get consistency with in single digits.

 

[DoneNOut]

Choosing a powder that packs the case keeps my ES/SD lower. I hum around 4-12SD. I accept anything under 20 when the recipe is shooting bug holes. Optimal combustion with low SD is only going to come into play at 1000yds and in a match shooting for inches.

 

[BiggBeans]

What i dont understand is when i am shooting an OCW Test and the load with the smalles ES and SD shoots the worst. And another load with like a 15-20 SD shoots under 1/2"

 

[DoneNOut]

What i dont understand is when i am shooting an OCW Test and the load with the smalles ES and SD shoots the worst. And another load with like a 15-20 SD shoots under 1/2"

When that happens the tuning is good, but he combustion is bad and vice versa.

 

[BiggBeans]

When that happens the tuning is good, but he combustion is bad and vice versa.

So powder charge or primer?

 

[DoneNOut]

So powder charge or primer?

Powder. Either the type or charge weight.

 

[BiggBeans]

Powder. Either the type or charge weight.

Might have to try different powders. Im charging on an auto trickler v3 fx120i

 

[DoneNOut]

Might have to try different powders. Im charging on an auto trickler v3 fx120i

You could put a tuner break, like an EC tuner to turn that great SD recipe into bug holes.

 

[Joe-boy]

1)Sounds like the situation is not too bad in the first place if grouping is like that. How about on longer ranges? Are the groups still consistent? The accuracy of the magnetospeed is 99.5%-99.9% so there is an error margin there as well.

2)How about your barrel cleaning routines? They also play a role here. A squeky clean barrel sometimes produces larger MV dispersion. Does the velocity stabilize after couple of dozen shots.

 

[Rick Richard]

Consistency in every aspect of the load recipe including sorting the cases by weight, which has given me the lowest ES and SD.