6.5 Creedmoor - Help me find my load

[shornik]

Hi guys,

First post here on the forum.

Did a workup of a new load in my Ruger Precision Rifle in 6.5 Creedmoor. I was looking for some input on what ya'll think my proper load might be? All loads printed within 1/10 of an inch of each other. I've included my data below.

I usually look for groups that print in the same vertical place indicating a node and consistent velocity. I also read of another method where you look for plateau's, or flat-spots in your velocities measured off the chronograph. I did certainly see some flat spots, and the SD's shrank where the flat spots were as well, but the groups were all pretty good TBH. I'm hoping some more experienced eyes than mine can shed some light w/ this data that I can't see.

Many thanks!

Ruger Precision Rifle 24" Barrel 1:8 Twist
H4350
Sierra 142 gr. Matchking
Hornady Brass / CCI BR-2 Primers
Seated .020" off the lands * (3.214" from the OGIVE)
DA: 1400
Temp: 78
Humidity: 59
*Used MagentoSpeed V3 Chrono (which is why POI is 2" left), Kestrel, & IR Thermometer for Barrel Temp.


*Note: Cold Clean Bore for 1st Shot was 40 fps slower. This is a trend.

Was a Beautiful Day for an initial reloading session w/ the RPR:

 

[JW74]

Groups 2 and 4 look good. Possibly a pulled shot on each? What is your barrel length? The velocities seem a little slower than I would expect. I am running 41.4 grains of H4350 under a 140gr Berger Hybrid @ 2731 fps out of a 26" barrel.

 

[shornik]

Groups 2 and 4 look good. Possibly a pulled shot on each? What is your barrel length? The velocities seem a little slower than I would expect. I am running 41.4 grains of H4350 under a 140gr Berger Hybrid @ 2731 fps out of a 26" barrel.

I have a 24" stock barrel on the Ruger Precision Rifle right now. Could be a pulled shot, I didn't call any fliers to be fair. The squares are Half Inch squares so they weren't terrible fliers

I really want to choose #6, 42.0gr. because of the SD value of 1.4, but #5 prints to a different area vertically than say 6 or 7.

Does anyone have any insight on the correlation between low SD values and nodes? I'm trying to figure out if they typically trend together.
In other words, are the nodes and low SD values such as the 1.4 often found together?

 

[47guy]

id go with the 42g load and play with seating depth .010 each way just to see if it tightened up any. if you look at either side of the 42g load everything is the same...
41.7g 13fps es 1/2' group
42g 2fps es 1/2" group
42.3 12fps es 1/2' group
all of those numbers are respectable out of a factory rifle and i really doubt your 42g load is going to produce a 2fps es every time out....i bet if you go out and chrony that load again it will be right in line with the 41.7 and 42.3 grain loads.

you have a better flat spot at 2617-2629 but personally ill take a little looser load for a little more velocity especially when the numbers line up like yours do.

 

[canezach]

See that flat spot on your graph between 2658 and 2663? That's the plateau you mentioned in your post. Your node is there and your desired charge weight will be around those charge weights, so somewhere from 41.7 to 42.0 grains. You have a couple of choices; 1) You could load up at 41.8 or 41.9 (or 41.85 if you have that resolution in your scale) and proceed to seating depth tests, or 2) do another test in finer increments and go just below that 41.7 and just above that 42.0 charge weight, like 41.6 and up to 42.2 or so, since you have data for 41.4 and 42.3, just to see where your node really starts and ends.

With that said, how did you shoot your groups? Was it round-robin, where you shot one round of each charge weight? What was your interval between shots?

 

[isofahunter]

FWIW I ended up at 41.9 after doing my LD.

 

[Jefe's Dope]

If you're shooting for distance, #6 would be where I would start refining from. The spread on your groups is small enough for me to consider the human error factor enough that none of your groups are significantly better than the others. And the the fact you're using a Magnetospeed for velocities could factor in to your groups as well. It's in the flat spot of the node and the SD AND ED are incredibly small. And 42 gr. of 4350 seems to be the starting point for many shooting a similar set up.

*Take my comments w/ a HUGE grain of salt as I'm just a noob.

 

[shornik]

See that flat spot on your graph between 2658 and 2663? That's the plateau you mentioned in your post. Your node is there and your desired charge weight will be around those charge weights, so somewhere from 41.7 to 42.0 grains. You have a couple of choices; 1) You could load up at 41.8 or 41.9 (or 41.85 if you have that resolution in your scale) and proceed to seating depth tests, or 2) do another test in finer increments and go just below that 41.7 and just above that 42.0 charge weight, like 41.6 and up to 42.2 or so, since you have data for 41.4 and 42.3, just to see where your node really starts and ends.

With that said, how did you shoot your groups? Was it round-robin, where you shot one round of each charge weight? What was your interval between shots?

Thanks for the info! I shot them left to right, each lot at a time. Normally I would shoot 1 of each type, but since I had my IR thermometer, I could make sure the barrel temp stayed within 10 deg.

 

[flyfisher117]

What target is that? Will be reloading for my 6.5 RPR shortly, just need the weather to improve a bit.

 

[shornik]

What target is that? Will be reloading for my 6.5 RPR shortly, just need the weather to improve a bit.

I just made some targets in Excel and purchased some cheap dots on Amazon. Here's a .PDF of the targets so you can print them out. I've also included the amazon link for the stickers. Hope this helps!



Splatterburst Targets 1 Inch SimpleSpot Adhesive Shooting Targets, 640 Targets, (Pack of 10)
by Splatterburst Targets

http://a.co/gvfzZMX