Help a Rookie Reloader Interpret Load Development - 6.5 CM

[TSpork]

Alright guys, I'm still fairly new to the whole reloading thing, and need some advice.

Rifle:
Impact Action
PVA 6.5 Creedmoor Cut rifled Barrel

I bought 600rds of the 140gr Berger 6.5 Creedmoor ammo. So Far I've shot 200 of them, and am beginning reloading the once fired brass so that by the time I get through them, I'll have a load ready to go.

I loaded 5 shots each starting at 41.0gr to 43.1gr of powder in 0.3gr increments 42.8 and 43.1 had slightly compressed charges.

Load:
H4350 41.0-43.1gr
140gr ELD-M 0.020" off the lands
Lapua SRP Brass
Fed 205M

All groups shot had their velocities recorded on the chart below. Also, 41.0 I may have thrown that first shot.

Attached is a Chart of the load vs velocity. The Error bars shows the extreme spread of the velocity and the number in front of the velocity were the SD of the load. Note: 41.0gr and 41.9gr only had 3 of the 5 shots recorded (forgot to turn on the labradar)

Here's what the fired brass looks like
L-R: 41.0, 41.3, 41.6, 41.9, 42.2, 42.5, 42.8, 43.1

Primer cratering:
There looks to be a ring around the firing pin strike on all the primers from all the charges. They are visible, as evidenced by the picture, but cannot be felt running a nail over it until 41.6gr. 41.6 to 43.1 you can feel it with your nail.

Primer flattening:
This one is a little hard for me to spot, so I could use some help with this one. I think there's some flattening at 43.1, and maybe earlier, but it's hard to tell. I feel like my eyes keep playing tricks on me.


Any advice on where to go from here? The primer cratering is concerning. I noticed when I got home that the bolt had some lube on it where there was none, so I'm wondering if the grease from the lugs ran a little and got in the chamber and am causing false pressure signs. But also, it seems like my velocities are kind of high from my research.


Should I try to clean my chamber with a mop and alcohol and rerun this test again to see if i still get pressure signs? Should i start lower like 39.5 or 40.0? I also have all 5 pieces from each charge weight separated so i can take more pics and post it if need be. I'm wondering why i'm getting primer cratering even at 41.0 with the impact action.

I'd definitely appreciate any help guys!

 

[FarmBoy87]

42.2 and try seating 20 out and 20 in...the primers look fine...some guns just crater

 

[Jabot]

What farmboy87 said

 

[Jabot]

And try 41.0 again

 

[TheOfficeT-Rex]

Second vote for 42.2 and moving to seating depth.

 

[TxWelder35]

X3 on rolling up 42.2

move the seating depth .003 at a time .020-.025 deeper than where you are at now.

 

[BLKWLFK9]

I mean, honestly, i didnt read your post as i just looked at your pics but whatever seating depth you had with the 42.2 seems like a good group for 6.5cm. Sure, you could probably tighten it up but you wont ever miss a target due to your grouping with what you found right there. Either way, if you wanted to possibly tighten it up, 42.2 is your charge weight i would go with.

 

[Hoyt7mm]

Look at 41 and 42.2. Load up +/-.1 in each to make sure you're in the middle of the node. Once you find that, play with seating depth if you want.
But, as said above, 42.2 is plenty good enough to just run as is.

FYI on primer flow: I have this constantly happen with all of my impacts, mostly when using SRP brass. I don't know what it happens (I run a lower node and FL size .001") but I have learned to not use it as an indicator of pressure. YMMV

 

[BLKWLFK9]

My nucleus action will crater a load that is 3 grains below book max. doesn't matter what the pressure is so i dont even look at the primers. That is due to firing pin diameter and not pressure.

 

[Dthomas3523]

Classic case of looking at the best group and smallest numbers. The groups and numbers on either side of 42.2 are not that good. The minute something changes, there is no node to be inside of to account for the changes. Also, you can make any load shoot well @100 with seating depth.

41.0-41.3 has good consistent numbers. That’s a good powder node.

 

[Batemanb12]

42.2 and try seating 20 out and 20 in...the primers look fine...some guns just crater

This is what i would do...

 

[Dthomas3523]

Also, if this was shot using a magnetospeed, the groups mean nothing.

 

[TxWelder35]

Classic case of looking at the best group and smallest numbers. The groups and numbers on either side of 42.2 are not that good. The minute something changes, there is no node to be inside of to account for the changes. Also, you can make any load shoot well @100 with seating depth.

41.0-41.3 has good consistent numbers. That’s a good powder node.

you happen to listen to franks podcast with the guys from Berger about reloading Recently? Seems they don’t believe in the whole “flat spot” line of thinking. I would have said the same thing before listening. They say find a powder charge with small sd/es and tube the load after that. Erik Corinta seems to say the same. I was going off smaller es/sd

 

[Dthomas3523]

you happen to listen to franks podcast with the guys from Berger about reloading Recently? Seems they don’t believe in the whole “flat spot” line of thinking. I would have said the same thing before listening. They say find a powder charge with small sd/es and tube the load after that. Erik Corinta seems to say the same. I was going off smaller es/sd

Erik Cortina looks for several charge weights that exhibit low es across them.

I’ve been to his class. He specifically cautions against looking at the smallest single ES. He also doesn’t shoot groups to find a powder charge.

Also, I never said anything about flat spots.

 

[BLKWLFK9]

Erik is my next guest on the podcast. I can't wait b/c i have so many questions myself. Its gonna be a good episode for sure.

 

[Cascade Hemi]

I'd load 40.6 to 41.2 in .2gr increments and reshoot. You're over max and the chronograph says your rifle doesn't like the load combinations.

 

[NW Valkyrie]

For many 6.5 Creeds a 140gr quality bullet at ~2,800 fps is money. I agree to stick with 40.6-41.2 and abandon the higher charges.

Once you settle on charge, play with seating depth and your load development is done.

 

[rjacobs]

They say find a powder charge with small sd/es and tube the load after that. Erik Corinta seems to say the same. I was going off smaller es/sd

Erik Cortina looks for several charge weights that exhibit low es across them.

I’ve been to his class. He specifically cautions against looking at the smallest single ES. He also doesn’t shoot groups to find a powder charge.

Ive been loading with this method for, maybe, 4 years now. I can crank rounds into a 25 yard berm and get my numbers. OBVIOUSLY there is confirmation after the fact that the load is indeed good, but it takes the indian out of the equation so to speak. So much easier than the ol "did I pull that one shot" "was I shaky on that string" "was the wind doing something weird"... nope, just read chrono numbers and away you go.

 

[BigJimFish]

My goodness that is some textbook looking load development data. Definitely load up a group or two more at 42.2 as it looks like you may have something there. I might also load another string of 41.0 as there is a pretty tight nucleous there as well.

 

[Dthomas3523]

Ive been loading with this method for, maybe, 4 years now. I can crank rounds into a 25 yard berm and get my numbers. OBVIOUSLY there is confirmation after the fact that the load is indeed good, but it takes the indian out of the equation so to speak. So much easier than the ol "did I pull that one shot" "was I shaky on that string" "was the wind doing something weird"... nope, just read chrono numbers and away you go.

The only confirmation needed is to get seating depth and make sure bullet BC is consistent enough from bullet to bullet to stay within whatever desired precision you have.

Other than that, there’s nothing else involved. The powder load is the powder load. As long as you’re loading with a good scale and you keep your brass prep consistent, there’s not too many other variables. If the load “falls apart at distance” it’s either the shooter or the bullet.

 

[supercorndogs]

I'd load 40.6 to 41.2 in .2gr increments and reshoot. You're over max and the chronograph says your rifle doesn't like the load combinations.

This is along the lines I was thinking. If the O.P was using Hornady brass those charges would be appropriate. Lapua brass has less capacity.

 

[rjacobs]

The only confirmation needed is to get seating depth and make sure bullet BC is consistent enough from bullet to bullet to stay within whatever desired precision you have.

Other than that, there’s nothing else involved. The powder load is the powder load. As long as you’re loading with a good scale and you keep your brass prep consistent, there’s not too many other variables. If the load “falls apart at distance” it’s either the shooter or the bullet.

I shoot all semi auto guns so seating depth is basically set: as long as it can be and still feed from the mag. I run KAC metal mags as they offer the longest seating distance of any SR25 pattern mag(Larue is a close second).

And by confirmation I mean taking the load out to distance and making sure its still consistent(I havent had an issue yet).

Loading over the chrono is such an easier technique than shooting groups or ladders or what have you. Such a time saver.

 

[Dthomas3523]

I shoot all semi auto guns so seating depth is basically set: as long as it can be and still feed from the mag. I run KAC metal mags as they offer the longest seating distance of any SR25 pattern mag(Larue is a close second).

And by confirmation I mean taking the load out to distance and making sure its still consistent(I havent had an issue yet).

Loading over the chrono is such an easier technique than shooting groups or ladders or what have you. Such a time saver.

If it doesn’t hold up and you’re shooting properly, start looking at the bullets (weight, length, consistency). If your MV is consistent, that’s where the problem will be.

 

[TSpork]

Thanks for the help guys. really appreciate it.

Sorry been MIA, my computer decided it no longer wanted to turn on anymore so definitely glad I posted Thursday night as opposed to yesterday. Right now I’m using my phone.

I should have been more specific, all shots were chronoed with a Labradar and not a magentospeed.

So it seems like a lot of people are recommending 41.0 and 42.2, which is kinda what I figured would happen. What started to worry me was that the velocity data shows that they’re flying pretty fast compared to most people. I forgot to add that it’s a 26” barrel.

I’m thinking maybe load 10 rounds at each charge at 40.9, 41.0, and 41.1 and another 10 for 42.1, 42.2, and 42.3. That way I can shoot 2 groups of each charge so I have a little more data.

Thoughts on this? Or am I pushing the load too much and should abandon the 42.2 all together?

 

[Dthomas3523]

I wouldn’t even bother with 42.2 just because the ES on either side jumped drastically.

41.0 and 41.3 were consistent. If you’re dropping your powder on a good scale and keeping your brass prep pretty consistent, I’d just run 41.1 in summer and 41.2 in winter and do seating depth test and be done. (Provided they both work with a water test for pressure)

If you’re not confident in your charge and brass prep, run the whole thing again and see if your numbers are consistent.

 

[rjacobs]

41 to 42.2 is about exactly 3% which is where your nodes should be... 3% in between nodes. 3% of 41g is 1.23 so 42.23...

So you are in accuracy nodes there for sure.

BUT as dthomas says, your 41g load to your 41.3 your ES/SD is not as jumpy as your loads surrounding your 42.2g load, I would probably play with that 41g load. Load 5 round loads in .1g increments +-.5g... so 40.5, 40.6, etc... to 41.5 to really zero in on it. Shoot em over the chrono and you will see your answer in the numbers. This will give you a very stable load that if your thrower throws .1 high or low, the temp changes, etc... you will still be ok.

 

[LostInJersey]

Honestly, I like the 41gr group. Clearly 1 flyer. Numbers are consistent.

 

[TSpork]

Update:
just finished loading rounds from 40.5-41.4gr in 0.1gr increments.
5 rounds each

 

[Gustav7]

Update:
just finished loading rounds from 40.5-41.4gr in 0.1gr increments.
5 rounds each

If you're doing this for the sake of learning, and improving your shooting, then go for it. Just know that you probably don't need to load that many up and down the node path.

Like @Dthomas3523 said, just load in the middle and confirm it.

That being said, I did full load developments and confirmation at distance for my AR like 5 times. I did this mainly to learn more, get experience loading for it and shooting, and I also don't compete so it was a little for curiosity and fun. When I got my bolt gun last year, I definitely did a quicker version of load development, got my load, and now I just practice at 100yds and 300yds. Once crops are off, I'll have out to 700yds to have fun.

 

[Deleted member 113831]

Primer is noticably flatter at 41.9
42.5 has an obvious ejector imprint.
I would treat 42.2 as a max charge.

 

[TSpork]

Thanks for the help guys. Tomorrow is my first match (shooting factory Berger 140s). After that I’ll shoot those rounds off and report back. I haven’t decided if I’ll shoot them all or just work up in 0.2 to save components and barrel life.

I just got my computer working (hard drive failure), so I’ll be able to post up the results

 

[TSpork]

Primer is noticably flatter at 41.9
42.5 has an obvious ejector imprint.
I would treat 42.2 as a max charge.

Thank you! Appreciate the feed back. I noticed the primers seemed a little flatter but couldn’t quite nail down where they started to get flatter

 

[briang7511]

agree with those who say 41.0 needs more testing. see how wide that node is. thats what i would run with. 60-70 fps more for a narrow node is not worth it. consistency is key.

 

[TSpork]

Okay guys, I did a lot better than I was expecting, and am definitely going to be shooting in next month’s match! I didn’t get a chance to shoot my reloads, but last night I tried chambering one, and now I’m scratching my head.

The first picture is a round before I chambered it.

The second picture is after chambering it. Notice the marks? These marks go almost all the way around. Chambering it, there was some resistance when closing it and turning my bolt handle down. I’m assuming it’s into the rifling and turning my bolt handle down is scraping it against the rifling.

I’m scratching my head because I’m using the same die setting as I did last time when I was jumping 0.020”. My last reloads I wasn’t experiencing this at all and the die was at the same setting.

Any idea what’s going on? My reloading gear is all put away, but this weekend I’m going to get my bullet comparator out and try and see if it’s measuring any different than my first reloads. Last time I Ioaded, I didn’t measure with the Bullet comparator because it was the same die setting as the time before

 

[Deleted member 113831]

Okay guys, I did a lot better than I was expecting, and am definitely going to be shooting in next month’s match! I didn’t get a chance to shoot my reloads, but last night I tried chambering one, and now I’m scratching my head.

The first picture is a round before I chambered it.

The second picture is after chambering it. Notice the marks? These marks go almost all the way around. Chambering it, there was some resistance when closing it and turning my bolt handle down. I’m assuming it’s into the rifling and turning my bolt handle down is scraping it against the rifling.

I’m scratching my head because I’m using the same die setting as I did last time when I was jumping 0.020”. My last reloads I wasn’t experiencing this at all and the die was at the same setting.

Any idea what’s going on? My reloading gear is all put away, but this weekend I’m going to get my bullet comparator out and try and see if it’s measuring any different than my first reloads. Last time I Ioaded, I didn’t measure with the Bullet comparator because it was the same die setting as the time before

To my eyes, the chambered round is visibly shorter.

Don't know what is going on, but something has changed. In fact, it looks different enough, that I would suspect a full rotation error on your seating die micrometer. I've done it before myself. Have you touched the die at all?

 

[TSpork]

To my eyes, the chambered round is visibly shorter.

Don't know what is going on, but something has changed. In fact, it looks different enough, that I would suspect a full rotation error on your seating die micrometer. I've done it before myself. Have you touched the die at all?

I think we have a winner! On my first test, around 42.8 and 43.1, I had to increase the pressure by 0.005” to get the same seating depth due to a compressed charge. I may have turned the die the wrong way and went outwards instead of in to set it back.

That would make sense since one full turn is 0.025”, and I was 0.020” off the lands. That means that I was jamming in 0.005”

 

[TSpork]

Okay,

So I went to go measure the rounds today. The chambered and unchambered rounds all measured 2.133” distance to I give using a 5-26 comparator.

The die was at the correct setting, although seating 0.005” farther than before. This is a little off because I thought setting my die to 75 would give me 2.128”. But I guess I’m seating them 0.005” off, which gives me a jump of 0.015” instead of the 0.020”. The last time I measured the lands it was 2.148” to the lands using the same bullet. So I’m kinda scratching my head why I’m having a hard close and scraping if I’m supposed to be 0.015” from the lands still.

This barrel has about 350ish rounds through it. Has only been cleaned for break in.
Any other ideas? I’ll try to measure the distance to lands again

 

[Dthomas3523]

Okay,

So I went to go measure the rounds today. The chambered and unchambered rounds all measured 2.133” distance to I give using a 5-26 comparator.

The die was at the correct setting, although seating 0.005” farther than before. This is a little off because I thought setting my die to 75 would give me 2.128”. But I guess I’m seating them 0.005” off, which gives me a jump of 0.015” instead of the 0.020”. The last time I measured the lands it was 2.148” to the lands using the same bullet. So I’m kinda scratching my head why I’m having a hard close and scraping if I’m supposed to be 0.015” from the lands still.

This barrel has about 350ish rounds through it. Has only been cleaned for break in.
Any other ideas? I’ll try to measure the distance to lands again

Clean throat so that’s not an issue.

Take the firing pin and ejector out of the bolt.

Insert piece of brass (fired and sized ideally) and make sure the bolt falls free with gravity or has very very little cam over resistance

Seat a bullet and make sure the bolt falls free with gravity or has the same very small cam over resistance as the brass.

If the bolt is tight on the brass, you have a sizing issue. If it doesn’t and is tight with bullet in, your bullet is into the rifling.

 

[TSpork]

Clean throat so that’s not an issue.

Take the firing pin and ejector out of the bolt.

Insert piece of brass (fired and sized ideally) and make sure the bolt falls free with gravity or has very very little cam over resistance

Seat a bullet and make sure the bolt falls free with gravity or has the same very small cam over resistance as the brass.

If the bolt is tight on the brass, you have a sizing issue. If it doesn’t and is tight with bullet in, your bullet is into the rifling.

thanks Dthomas.
I’ll give that a go. I still have about 100 brass that has been prepped already and once fired that I can use. I’ll seat one and try that.

I’ll try to measure again with my hornady OAL gauge to see where the lands are again and see if I get something different

 

[Dthomas3523]

thanks Dthomas.
I’ll give that a go. I still have about 100 brass that has been prepped already and once fired that I can use. I’ll seat one and try that.

I’ll try to measure again with my hornady OAL gauge to see where the lands are again and see if I get something different

Do the above test and you’ll know immediately if it’s your brass or the bullet making things tight.

 

[Ffjmoore]

I had 2 accuracy nodes around the same weights. I stick with 41.2 on my rifle but was another node just above 42

 

[TSpork]

Do the above test and you’ll know immediately if it’s your brass or the bullet making things tight.

So I chambered a brass, and it fell without resistance.
Tried chambering with a seated bullet, and it encountered some slight resistance right about here:

When I put the slightest bit of pressure on the bolt, it falls leaving these marks

Measuring with a Hornady OAL Gauge, I got a length of 2.055” length to Ogive with a 5-26 comparator when it touches the lands. The bullet when seating to the lands seems really short.

I was seating to 2.128” before and didn’t have a problem. That means I was 0.073” into the lands? That doesn’t seem right to me. I feel like I should have encountered resistance at the 2.128” setting. I didn’t notice a problem until my bullets were seated 2.133”. Any thoughts on this?

 

[TSpork]

Bump.

Any words of advice?

 

[Whiskey_Tango6.5]

Looks pretty short, whats the COAL?

 

[Precision Underground]

I agree with others that you don’t want to look for the smallest groups. But your 42.2 has .3 above and below it. I’d be loading 42-42.4 in .1 increments @.10 off the lands and see how they group. That range is where most people’s load lands and if they all have the same vertical print you should be fine to pick 42.2. My question would be at what point does the vertical change you see at 42.5 on the test target happen. If it’s at 42.5 you’ll be fine. If it’s at 42.3 that will narrow your node significantly. You can tweak seating depth if the groups aren’t quite what you want but are consistent.

 

[TSpork]

Looks pretty short, whats the COAL?

2.667”

It is super short. I don’t know why I was able to so easily seat it almost 0.073” longer without noticing it touching the lands. Not sure what’s going on

 

[TSpork]

I agree with others that you don’t want to look for the smallest groups. But your 42.2 has .3 above and below it. I’d be loading 42-42.4 in .1 increments @.10 off the lands and see how they group. That range is where most people’s load lands and if they all have the same vertical print you should be fine to pick 42.2. My question would be at what point does the vertical change you see at 42.5 on the test target happen. If it’s at 42.5 you’ll be fine. If it’s at 42.3 that will narrow your node significantly. You can tweak seating depth if the groups aren’t quite what you want but are consistent.

Much appreciate the help. I might give that a shot once I get this seating depth puzzle figured out.

I’m not sure why it appears I’m touching the lands with a such a short cartridge length to ogive.

Pushing it forward with the Hornady gauge as I measure it, I’m sure it’s hitting the lands. It even sometimes gets stuck and I have to knock it out

 

[Precision Underground]

Much appreciate the help. I might give that a shot once I get this seating depth puzzle figured out.

I’m not sure why it appears I’m touching the lands with a such a short cartridge length to ogive.

Pushing it forward with the Hornady gauge as I measure it, I’m sure it’s hitting the lands. It even sometimes gets stuck and I have to knock it out

That’s odd for sure. Have you measured the factory Bergers that you were shooting? I would guess their BTO would be longer than that but I don’t shoot factory ammo so maybe I’m wrong.

 

[sirhrmechanic]

Lots of good info in this thread and the OP did well right from the get go!

One thing to reiterate is that single groups don’t tell much. After initial series, it looks like you have a middle-charge that is pretty consistent. And the 41 looks pretty good too.

Picking one of those charges (and a seating length) and loading up about 50 cartridges... enough to do ten 5 round groups will let you know if you are there. Then do another 50 up or down a bit... see what you get.

The single 5 shot groups get you right into the ballpark. But confirm your best load with more groups from the same batch. The you will have a load matched to your rifle!

Great thread and, as I said, a lot of good info here!

Sirhr

 

[Whiskey_Tango6.5]

Berger lists 140 Hybrid Target Load at 2.810 COAL for reference. What bullet are you loading and what bullet was in the factory ammo?

6.5 mm Creedmoor 140gr Hybrid Target Rifle Ammunition

The Berger 6.5mm 140gr Hybrid target bullet is one of the top performing bullets in long range precision rifle target style competitions. If you want to get the best long range performance out of your single fed bolt gun chambered in 6.5 Creedmoor, this is the load for you.

bergerbullets.com

You may have an issue with your comparator? I know that a 156 EOL will bottom out in a Hornaday comparator.