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New 6mm Advanced Rifle Cartridge

Shot reloads for first time through the ARC. Today was OCW testing. Went from 28.0 to 29.4 in .2 grain increments, focusing on velocity. I’ll worry about seating depth and tuner settings next trip.

28.0: 2587
28.2: 2617
28.4: 2638
28.6: 2671
28.8: 2695
29.0: 2704
29.2: 2730
29.4: 2758

Looks like a good node between 28.8 and 29.0. I’ll load some at 28.9 for the seating depth test.

24” Bartlien barrel, 105 berger hybrids jumped .070” (limited by elander mag length), once fired Hornady brass.
 
Brass from 29.4 load. I don’t see any pressure signs.
 

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When you say stripped bolt, do you mean no Firing Pin or is there more to it than that. I'd like to confirm my measurements a bit more in this area. I have the Hornady comparator set.

That looks great results on the reloads! If you zoom in close you can see the center of the primers starting to protrude back out just a tad. On some of my hotter loads it is a little more pronounced than that even, but I don't haven any hard primers so im stuck in the 2600ish range for now. Whats the deal with the sharpie mark, did you hand feed and index them or something?

I just got some new glass on the Poverty Pony. No excuses this time. I went with the Valdada 16x56 fixed power MOA. It's pretty nice and I think I can get most all my target yardages with holdovers only and no dialing - sight in this weekend hopefully.

I just hot washed and deprimed ~250 cases of starline converted brass last night. I think some of it was also annealed after firing but most wasn't so I'm just saving it for annealing next range trip.

After that though, I will be forming it with the body die/bump (~4 thou) no center spindle/expander ball, Manderal Die expand, then check trim len. champher/deburr and run'em again on the D650. The theroy being that the manderel die will center the necks a tad more.
 
When you say stripped bolt, do you mean no Firing Pin or is there more to it than that. I'd like to confirm my measurements a bit more in this area. I have the Hornady comparator set.
When I say "stripped bolt”, I mean extractor and ejector removed. The ejector is the main thing that won’t allow you to get correct headspace readings since it has so much force behind it with the ejector spring.

I used one of my bolt disassembly tools to punch out the roll pin that retains the ejector and I keep that bolt in that state specifically for determining headspace for my sizing process.

I seat a sized empty case in the chamber and then see if I can rotate that stripped bolt into a locked position in the barrel extension. If it won’t turn easily, I keep sizing the shoulder back until it will reliably do so with several pieces of brass.

The last time I did it with Grendel, it worked out to be the same headspace across all my semi autos and Howa bolt gun, which was fortuitous.

That Hornady comparator set is a great tool to have for this reason, far more effective than case generic gauges.
 
Sweet - This is now on my list of to dos. Let me ask this as a follow up:
Right now I run a lightweight BCG but have a spare normal BCG
How can I measure the lugs per se to make sure they are the same.
When doing this process would it be advantageous to have both bolts out and testing at the same time to see which one locks up first?
I'm new to ARs - thx for the tips.
 
For those who have conducted seating depth testing with Berger 105s: where did you end up at?

Here is my target for today. Corresponding jump values next to target. I tried to go in .003” increments but the Hornady dies don’t have a micrometer.

Looks like it doesn’t like being between .040-.050 jump. I could maybe try a .035” jump but I’ll be pretty close to mag length. .052” or so may be the ticket. I’ll go back with 5 round groups at .052-.060 next.
 

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I tried to go in .003” increments but the Hornady dies don’t have a micrometer.
Hornady sells a micrometer top for their seating dies. The great thing about them is you can buy 1 mic and use it on your other Hornady rifle dies. You just note down the mic readings for whatever bullets you're using on the other caliber dies.


Seems everyone is out of them right now, but for $30.00, they are a good deal. Get on a backorder list.
 
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Sweet - This is now on my list of to dos. Let me ask this as a follow up:
Right now I run a lightweight BCG but have a spare normal BCG
How can I measure the lugs per se to make sure they are the same.
When doing this process would it be advantageous to have both bolts out and testing at the same time to see which one locks up first?
I'm new to ARs - thx for the tips.
As long as the lug lengths and bolt face depth are the same, the headspace will be the same for the test bolt vs the bolt being used.

I’ve measured a lot of Grendel bolts and found that most of them have the same lug lengths and face depth.

I’ve seen some that other people wanted to use for builds that had too deep of a face (excess of the .136” depth), but I don’t recall any right now that were shorter. The Grendel bolt is -.003” allowable, no + allowable.

The main dimensional variation I’ve seen is bolt overall length, with a lot of imitation bolts being 2.800” vs the 2.810” required to use standard firing pins.
 
Whats the deal with the sharpie mark, did you hand feed and index them or something?
No, that's just how I mark my brass. I've been squaded with people at PRS matches that use the same brass and same color exterior marking as me before so this is an additional mark.

Also it helps keep tabs on how many loadings are on the brass. I use 1 mark for every time I load it.
 
Sweet - This is now on my list of to dos. Let me ask this as a follow up:
Right now I run a lightweight BCG but have a spare normal BCG
How can I measure the lugs per se to make sure they are the same.
When doing this process would it be advantageous to have both bolts out and testing at the same time to see which one locks up first?
I'm new to ARs - thx for the tips.

Better to just swap your current bolt to the new carrier if you're going to change.

Headspace should be fine with either one, but like any mechanical parts that work together, your bolt starts seating against the carrier more evenly as parts wear together. This is a good thing for even bolt lug loading and longevity, but swapping bolts around starts the whole process again.
 
So I think I have to call my seating depth testing a fail. Doesn’t look like it matters how much I jump, I get the same accuracy results.

Bullet jump values next to respective targets below.
 

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I find that the Berger bullets don't like a long jump. I am loading them to 2.950 to 2.300 OAL. But I am now shooting their 115 grain bullets in my bolt action and they do very well. The Nosler RDF's I load on the other hand love a longer jump, but do well with a short jump to. You usually find a couple nodes when testing. I change my jump in .030 increments and find the tighter groups and then fine tune from there.

Your groups look pretty good, but each barrel likes something different, I have four ARC's and each one likes a different load, would love to find a universal load for my gas guns though. I may work on that but one of them has a match grade barrel on it to compete in PRS gas gun, and my bolt gun is a totally different animal all together, I have to keep that brass segregated from the gas stuff.
 
So I think I have to call my seating depth testing a fail. Doesn’t look like it matters how much I jump, I get the same accuracy results.

Bullet jump values next to respective targets below.
You didn’t test across a very wide range so you might just be missing the best node. I try to cover a range spanning.100”-.150” for a good seating depth test, depending on the situation. If it were mine, I’d be testing both less jump and more. Maybe .010”-.110” etc.

The other part of a seating depth test is to find the depth that is most tolerant of variations in velocity or powder charge. To do that, I like to mix 5 different charge weights for each seating depth. For example maybe 30.0gr to 31.2gr in 0.3gr increments for each seating depth. This shows more dispersion at some depths and let’s you zero in better on the right jump.

Hope that makes sense. Might sound confusing at first but it’s actually fairly simple and works well.

(The powder charges I said above are not a recommendation for your load, just an examI used myself not long ago.)
 
I was being somewhat facetious with that last post. While it was true, getting consistent .3-.5 moa out of a gas gun is plenty good for me. The fact that I don’t have to worry about chasing lands is even better.

I tested between .030-.080 jump in .003” increments. Any less jump and I run into mag length issues. Deeper and I start compressing load and spiking SDs. These groups were where I suspected the best nodes may be.

Below is chrono data. 105 berger jumped .061 29.0gr lever evolution. Can anyone with quick load run that and see what pressures I’m around? I could probably push higher but don’t see the need to yet.
 

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What magazines are working out best for everyone shooting the 6mmARC at this point???
C-Products Duramags are getting good reviews. The e-lander mags work good, but limited cartridge length more than Duramags
 
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What magazines are working out best for everyone shooting the 6mmARC at this point???
I've been using my 6.5 Grendel CProducts and Duramags interchangeably in the ARC, no problems so far with the 10 Rd versions, which is what I almost always use at the range.
 
E-lander and ASC 15 rounders have been solid for myself and a couple buddies. E-lander 25's are fine unsuppressed in my experience, but the extra fouling from a suppressor will cause the magazine to run slower than the bolt.
 
Shot the Valdada fixed yesterday at 100 yds to zero. Glass is great and the side focus is nice. I've only seen a few great glass scopes so I can only compare to what I have (all < $200). Fire Formed about 50 more cases. Looking forward to stretching the legs with the new glass and holdovers.

The scope is also MUCH lighter than all the ATN stuff. I was amazed at how close to bore the scope/rings were when installing and didn't even make any adjustments until I got to the range and then it was ony ~1" high and right - super easy to sight in. So close in fact I wished I had just started at the 300 yd range but stuck at 100 for the day - whatevs...

I'm running Duramags with the blue follower, they are GTG. 10 rounders for load dev (usaually only shoot 5) and the longer ones for fun time.

Also scored 3 cans of W748 for free! - It's in the old antique bottles but I'm gonna run it in the new 6ARC. I have some old primers to use too. thinking old/new...
 
I'm patiently waiting for my 20" Proof carbon to get here. Supposedly July shipment. I have everything to build the rifle but the barrel, but no components to load still.
 
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Did a ladder test with the ARC over the weekend.

Enviro:
-85 F
-70% RH
-600' Elev

Load:
-Starline 6.5 Grendel brass
-Berger 108 Elite Hunter
-Hodgdon Leverevolution 27.2 - 30.0grs in 0.2gr increments
-Federal AR Match primers
-CBTO 1.655" (0.060" off lands)
-COAL (E-Lander mag length) ~2.25"

Rifle:
-20" 1:7.5 +2 rifle Rock Creek by Craddock Precision
-AGB
-Silencerco Omega

27.2 - 2479
27.4 - 2521
27.6 - 2543 light ejector marks started
27.8 - 2580
28.0 - 2594
28.2 - 2611
28.4 - 2630
28.6 - 2648
28.8 - 2698
29.0 - 2693
29.2 - 2702
29.4 - 2749 heavy ejector marks started
29.6 - 2726
29.8 - 2757
30.0 - 2798

Had some light ejector marks on the factory 105s. Need to adjust my AGB as well.

I also loaded 5 rounds at 29.0grs but didn't have time to shoot them. It looks like that is going to be the sweet spot, the same as many of you on here found.

Brass pic starts at 27.2 on the left and ends at 30.0 on the right, as well as the two factory 105s on the bottom.

I'll report back when I shoot 5 round groups near the node.
 

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Did a ladder test with the ARC over the weekend.

Enviro:
-85 F
-70% RH
-600' Elev

Load:
-Starline 6.5 Grendel brass
-Berger 108 Elite Hunter
-Hodgdon Leverevolution 27.2 - 30.0grs in 0.2gr increments
-Federal AR Match primers
-CBTO 1.655" (0.060" off lands)
-COAL (E-Lander mag length) ~2.25"

Rifle:
-20" 1:7.5 +2 rifle Rock Creek by Craddock Precision
-AGB
-Silencerco Omega

27.2 - 2479
27.4 - 2521
27.6 - 2543 light ejector marks started
27.8 - 2580
28.0 - 2594
28.2 - 2611
28.4 - 2630
28.6 - 2648
28.8 - 2698
29.0 - 2693
29.2 - 2702
29.4 - 2749 heavy ejector marks started
29.6 - 2726
29.8 - 2757
30.0 - 2798

Had some light ejector marks on the factory 105s. Need to adjust my AGB as well.

I also loaded 5 rounds at 29.0grs but didn't have time to shoot them. It looks like that is going to be the sweet spot, the same as many of you on here found.

Brass pic starts at 27.2 on the left and ends at 30.0 on the right, as well as the two factory 105s on the bottom.

I'll report back when I shoot 5 round groups near the node.
Looks like you have the same node and same jump that I ended up with. Not surprising since mine is also from Craddock and likely same reamer dimensions if not same reamer itself.
 
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Awesome data! - Are those AR Match primers hard primers? When I load up to 29.0 gns with 105s I get cratered primers and a couple pierced primers, backed off a bit. Need the hard primers... Your brass pics help gauge a lot as far as what is a bad ejector swipe - thx for sharing.
 
Awesome data! - Are those AR Match primers hard primers? When I load up to 29.0 gns with 105s I get cratered primers and a couple pierced primers, backed off a bit. Need the hard primers... Your brass pics help gauge a lot as far as what is a bad ejector swipe - thx for sharing.
Appreciate it, just trying to contribute.

Yes the AR primers are harder to protect against slam fires and the harder nature of AR's vs bolt guns I think.
 
Awesome data! - Are those AR Match primers hard primers? When I load up to 29.0 gns with 105s I get cratered primers and a couple pierced primers, backed off a bit. Need the hard primers... Your brass pics help gauge a lot as far as what is a bad ejector swipe - thx for sharing.

What primers are you using? Sounds like they are too soft for these pressures, although anything that handles 5.56 pressure will handle this cartridge easily since the pressure is lower.

If you’re not using a thin primer like Remington’s 222 / 22 Hornet primers or a pistol primer, it might be an indication of an oversized firing pin hole in the bolt. Something to check anyway.
 
Did a ladder test with the ARC over the weekend.

Enviro:
-85 F
-70% RH
-600' Elev

Load:
-Starline 6.5 Grendel brass
-Berger 108 Elite Hunter
-Hodgdon Leverevolution 27.2 - 30.0grs in 0.2gr increments
-Federal AR Match primers
-CBTO 1.655" (0.060" off lands)
-COAL (E-Lander mag length) ~2.25"

Rifle:
-20" 1:7.5 +2 rifle Rock Creek by Craddock Precision
-AGB
-Silencerco Omega

27.2 - 2479
27.4 - 2521
27.6 - 2543 light ejector marks started
27.8 - 2580
28.0 - 2594
28.2 - 2611
28.4 - 2630
28.6 - 2648
28.8 - 2698
29.0 - 2693
29.2 - 2702
29.4 - 2749 heavy ejector marks started
29.6 - 2726
29.8 - 2757
30.0 - 2798

Had some light ejector marks on the factory 105s. Need to adjust my AGB as well.

I also loaded 5 rounds at 29.0grs but didn't have time to shoot them. It looks like that is going to be the sweet spot, the same as many of you on here found.

Brass pic starts at 27.2 on the left and ends at 30.0 on the right, as well as the two factory 105s on the bottom.

I'll report back when I shoot 5 round groups near the node.

Looks good. I’ve noticed that Starline brass is pretty tough in this cartridge and handles a lot of pressure and abuse. In my 4 rifles that use this brass, it can be pushed way over pressure without showing pressure signs.

All of those cases look ok except the last couple; those ejector hole imprints are concerning since it’s Starline. If you haven’t, it’d be worth making sure your shoulder bump is correct; too much bump (creating excess headspace) can cause those imprints at higher pressure. The danger is that it also resulted in impending case head separation for me after a few loads and the brass was junked. Reducing bump down to minimum with the same loads let this brass handle 12 loads without any pressure signs.

Hope that helps.

I have a few disagreements with that method of load development but will keep it to myself because some people take it personally. The one thing I’ll say is that results on target matter a whole lot more than results over the chrono, and primers are hard to get right now...
 
Looks good. I’ve noticed that Starline brass is pretty tough in this cartridge and handles a lot of pressure and abuse. In my 4 rifles that use this brass, it can be pushed way over pressure without showing pressure signs.

All of those cases look ok except the last couple; those ejector hole imprints are concerning since it’s Starline. If you haven’t, it’d be worth making sure your shoulder bump is correct; too much bump (creating excess headspace) can cause those imprints at higher pressure. The danger is that it also resulted in impending case head separation for me after a few loads and the brass was junked. Reducing bump down to minimum with the same loads let this brass handle 12 loads without any pressure signs.

Hope that helps.

I have a few disagreements with that method of load development but will keep it to myself because some people take it personally. The one thing I’ll say is that results on target matter a whole lot more than results over the chrono, and primers are hard to get right now...
Thanks for the advice. Now that these are fire formed I will know exactly what to bump the Starline in the future. Hopefully the 29.0grs shoots well and I don't have to develop much after that.
 
I was being somewhat facetious with that last post. While it was true, getting consistent .3-.5 moa out of a gas gun is plenty good for me. The fact that I don’t have to worry about chasing lands is even better.

I tested between .030-.080 jump in .003” increments. Any less jump and I run into mag length issues. Deeper and I start compressing load and spiking SDs. These groups were where I suspected the best nodes may be.

Below is chrono data. 105 berger jumped .061 29.0gr lever evolution. Can anyone with quick load run that and see what pressures I’m around? I could probably push higher but don’t see the need to yet.
The previous chrono data you posted of the OCW testing does not line up with the 2718 fps of this post, but calibrated to the 2718 fps, pressure is estimated over 57K. (Without calibrating to actual velocity, the estimated velocity was lower, and the pressure was just under 54K, so between 54K and 57K is mu best guess) The optimal barrel time for a 24" barrel at node 5 is 1.228 ms, so I highlighted the node. In an AR15, with the gas block changing harmonics slightly, I find that 10-20fps faster than the node will shoot the best with lowest ES and SD, so I would suggest targeting 2670 to 2690 fps and see if that has the lowest ES/SD and smallest group. And yes, I know everyone wants to go fast, but run a ballistic calculation and see how little impact 30 or so fps has on the solution. (spoiler alert, not much)
 

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The previous chrono data you posted of the OCW testing does not line up with the 2718 fps of this post, but calibrated to the 2718 fps, pressure is estimated over 57K. (Without calibrating to actual velocity, the estimated velocity was lower, and the pressure was just under 54K, so between 54K and 57K is mu best guess) The optimal barrel time for a 24" barrel at node 5 is 1.228 ms, so I highlighted the node. In an AR15, with the gas block changing harmonics slightly, I find that 10-20fps faster than the node will shoot the best with lowest ES and SD, so I would suggest targeting 2670 to 2690 fps and see if that has the lowest ES/SD and smallest group. And yes, I know everyone wants to go fast, but run a ballistic calculation and see how little impact 30 or so fps has on the solution. (spoiler alert, not much)
Seems to me you’ve made some assumptions and correlations that don’t actually carry over from one barrel to the next. Barrel harmonics for example are highly dependent on barrel profile, not just length. And the optimum accuracy node from harmonics does not necessarily correlate to lowest ES/SD; those are independent of each other. You might see both of these occurring simultaneously in your barrel with that load, but it’s a bad assumption to conclude it works that way in other examples too.

I know that people who’ve spent good money for a software program don’t like to hear this, but this is a good example of the fact that just because you can generate a bunch of data doesn’t mean it’s accurate or useful.
 
Seems to me you’ve made some assumptions and correlations that don’t actually carry over from one barrel to the next. Barrel harmonics for example are highly dependent on barrel profile, not just length. And the optimum accuracy node from harmonics does not necessarily correlate to lowest ES/SD; those are independent of each other. You might see both of these occurring simultaneously in your barrel with that load, but it’s a bad assumption to conclude it works that way in other examples too.

I know that people who’ve spent good money for a software program don’t like to hear this, but this is a good example of the fact that just because you can generate a bunch of data doesn’t mean it’s accurate or useful.
I don't think my comment was misleading as I referred to the numbers as "estimated", numerous details were not provided to make any sort of true analysis. Garbage in equals garbage out. Even noted the chrono data does not match up, and I selected only the last to use to this estimate. And based on the numerous calculations I have provided for AR clients seem to pan out that the effect on OBT times that gas blocks, muzzle devices, etc. tend to push the assumed node a few fps higher, based on ES/SD and group size. Suppressors in particular impact the estimates. Also, calibration to actual velocities will skew the pressure estimates, so I identified an estimated range as my "best guess". I remind my clients of this because so many are used to the bolt gun numbers being spot on when we do a full analysis. This however was a "quickie estimate" to answer the question, in which I used saved criteria from other 6mm ARC clients, so it is obviously "ballpark", not exact.
 
I don't think my comment was misleading as I referred to the numbers as "estimated", numerous details were not provided to make any sort of true analysis. Garbage in equals garbage out. Even noted the chrono data does not match up, and I selected only the last to use to this estimate. And based on the numerous calculations I have provided for AR clients seem to pan out that the effect on OBT times that gas blocks, muzzle devices, etc. tend to push the assumed node a few fps higher, based on ES/SD and group size. Suppressors in particular impact the estimates. Also, calibration to actual velocities will skew the pressure estimates, so I identified an estimated range as my "best guess". I remind my clients of this because so many are used to the bolt gun numbers being spot on when we do a full analysis. This however was a "quickie estimate" to answer the question, in which I used saved criteria from other 6mm ARC clients, so it is obviously "ballpark", not exact.

You're still assuming correlations that don't exist. One is your comment about optimum barrel time and harmonics leading to lowest ES/SD; those are independent things and one does not cause the other. Another one is your assumption that you can estimate optimum barrel time based on barrel length alone.
Good for you if it's worked for you and your "clients" but IMO you're promoting bad understanding of how this stuff works.

In my experience if you just start off with good load development practices (NOT things like the velocity "node" search someone used above) you often end up at a very different result than trying to follow these predictions, because they lack enough input data to be actually useful.
 
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The first thing that I saw that caught my attention was the input data on case capacity in H2O, it was 34.8, that seems a bit high.

Bad data in...
 
You're still assuming correlations that don't exist. One is your comment about optimum barrel time and harmonics leading to lowest ES/SD; those are independent things and one does not cause the other. Another one is your assumption that you can estimate optimum barrel time based on barrel length alone.
Good for you if it's worked for you and your "clients" but IMO you're promoting bad understanding of how this stuff works.

In my experience if you just start off with good load development practices (NOT things like the velocity "node" search someone used above) you often end up at a very different result than trying to follow these predictions, because they lack enough input data to be actually useful.

The first thing that I saw that caught my attention was the input data on case capacity in H2O, it was 34.8, that seems a bit high.

Bad data in...
Pretty close, depends on chamber and brass brands. That was Hornady 6mm ARC stamped brass, using the actual average of measured fired cases where the length was close to the 1.48" trim length, average case weight 114.7, average water capacity 34.8 grains. Several cases were 1.49"+ after firing, the max water weight of the overlength cases was 35.04 grains. This is following the QL procedure for rifle cases, using an unresized fired case, using water at 75 degrees F. Using Lapua, Norma or Starline Grendel brass, the capacity will be over 35 grains. Using resized 7.62x39, the volume will vary depending on manufacturer, but most were less than Hornady. Oh, and anyone looking for real frustration, Federal Grendel brass resized to 6mmARC will also be less than Hornady.
 
Resized Hornady case trimmed to 1.480

33.9 grains of water, reason for the resized case is because your not going to fire one that is not the right size to fit the chamber.

Hornady brass is factory 1.183 to the datum line, this case was 1.185 to the datum line.

Hornady claims case volume to be 34 grains of water.
 

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The previous chrono data you posted of the OCW testing does not line up with the 2718 fps of this post, but calibrated to the 2718 fps, pressure is estimated over 57K. (Without calibrating to actual velocity, the estimated velocity was lower, and the pressure was just under 54K, so between 54K and 57K is mu best guess) The optimal barrel time for a 24" barrel at node 5 is 1.228 ms, so I highlighted the node. In an AR15, with the gas block changing harmonics slightly, I find that 10-20fps faster than the node will shoot the best with lowest ES and SD, so I would suggest targeting 2670 to 2690 fps and see if that has the lowest ES/SD and smallest group. And yes, I know everyone wants to go fast, but run a ballistic calculation and see how little impact 30 or so fps has on the solution. (spoiler alert, not much)
No, I think previous data had a lower velocity for the same powder charge. However that was with different seating depth and different ambient temperature. So far leverevolution seems to be sensitive to temps. I've gotten 30 fps variation on average velocities even though SDs were low. I'm not too concerned about it. I've never had to enter powder temp data into my kestrel but I will for this one.

My first match with this gun is in a week and will have shots beyond 1000. We'll see how it does.
 
Resized Hornady case trimmed to 1.480

33.9 grains of water, reason for the resized case is because your not going to fire one that is not the right size to fit the chamber.

Hornady brass is factory 1.183 to the datum line, this case was 1.185 to the datum line.

Hornady claims case volume to be 34 grains of water.
But for Quickload calculations, you use a fired case, with the spent primer still in it. (Page 64 of the latest QL manual I have downloaded, which also states "cold water", which is why I noted the water temp I use, which actually understates the case volume. I allow the water from a tap to sit for a bit to ensure no air bubbles from aeration is present, as it is at room temp. A simple mathematical calculation of water density could be performed to adjust to "cold water", but since the exact temp of "cold water" is not defined, I use the number from my testing. This slight error is the same way every time, consistent processes can be key) Even a fired case pulls back from the chamber walls, so both a sized or unsized case are not the actual size of the case as fired and formed to the walls. There are numerous variables in the process, and some argue they can adjust case volume to align with field results, I prefer to not adjust something that can be measured with a reasonable accuracy. Garbage in equals garbage out, so accuracy of measurements, in the manner defined by the program are critical. Too many people grab a copy of Quickload and get frustrated when it doesn't magically spit out a world class load, it is just one tool to help get there.
 
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No, I think previous data had a lower velocity for the same powder charge. However that was with different seating depth and different ambient temperature. So far leverevolution seems to be sensitive to temps. I've gotten 30 fps variation on average velocities even though SDs were low. I'm not too concerned about it. I've never had to enter powder temp data into my kestrel but I will for this one.

My first match with this gun is in a week and will have shots beyond 1000. We'll see how it does.
Good luck on the first match with that setup.
 
33.9 grains of water, reason for the resized case is because your not going to fire one that is not the right size to fit the chamber.

No, SWFShooter is right about that part; the volume that actually matters under pressure is that of the case pressed against the chamber walls.

Here's an interesting and semi-related detail to think about (and try yourself) - with the same load, a FL sized case will usually show less pressure and velocity than the same case neck sized only. The reason is that it takes a small amount of energy and time to blow the case out to chamber dimensions. With some loads and cartridges the difference can be so small as to be insignificant, but with others it can make a noticeable difference. Just one of those little odd details that doesn't quite make sense at first until you dig into it.
 
Has QL come out with a 6 ARC program yet? I know most folks are using a modified Grendel program, and I have yet to see accurate data from the modified Grendel program.

Makes sense using a fired case now that I think about it, I will have to measure one and see what I come up with. I was going to get the QL software for my ARC, but as I stated the information it spits out for this cartridge does not match up to well with real world results that I have seen. I know that it is dependent on user input.
 
Found new Starline Grendel brass in stock - 1k ordered. will post when they are actually on the way/arrived. They have 6.5CM in stock right now too.

On to waiting for primers and looking for more bullets.
 
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Found new Starline Grendel brass in stock - 1k ordered. will post when they are actually on the way/arrived. They have 6.5CM in stock right now too.

On to waiting for primers and looking for more bullets.
I ordered some a couple days ago, scheduled to deliver today. Didn't really need it but it was available. I have not seen anything Grendel in about a year. I know of a couple folks that have their rifles for sale because they can't shoot them.They must have a bunch of that brass if they still have it in stock.
 
Found new Starline Grendel brass in stock - 1k ordered. will post when they are actually on the way/arrived. They have 6.5CM in stock right now too.

On to waiting for primers and looking for more bullets.

Thanks for the link, just ordered more myself.
Starline seems to handle pressure better than Lapua in this cartridge, and uniformity seems to be nearly as good. I neck turn all my 6mm brass and both of these brands only need a couple thousandths taken off at most.
 
Has QL come out with a 6 ARC program yet? I know most folks are using a modified Grendel program, and I have yet to see accurate data from the modified Grendel program.

I agree; IMO I’ve yet to see any QL data posted for this cartridge that’s of any real value, and it doesn’t even seem to do a good job of predicting the best powders compared to published load data or my own experience.
 
Found new Starline Grendel brass in stock - 1k ordered. will post when they are actually on the way/arrived. They have 6.5CM in stock right now too.

On to waiting for primers and looking for more bullets.
The brass to order for reloading is the "Starline 6.5 Grendel Brass"? Why 1k instead of 500? Would you ever use more than 500 at a time? I'm just getting into reloading, and am trying to figure out best practices.
 
The brass to order for reloading is the "Starline 6.5 Grendel Brass"? Why 1k instead of 500? Would you ever use more than 500 at a time? I'm just getting into reloading, and am trying to figure out best practices.
Seems like a lot of people are buying large quantities just because there’s a shortage. Which of course drives more shortages. But other guys actually use it, especially the prairie dog shooters although I can’t speak for anyone here on that.

Personally, 1K pieces of something like 9mm brass isn’t nearly enough but in this cartridge I’d probably never use it all. With this recent order I’ll have 500 pieces of Starline, and my only reason for that much is that I use it in both 6.5 and 6mm so it’s just 250 for each. I have loaded some of this up to 12 times now, and when sized with proper shoulder bump it’s still working like new, so it lasts a long time.
 
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And of course, LVR is basically a bulkier version of CFE223.....

. And CFE223 has proven ... about equal to LVR with heavies,

No, and no. Yet another example of your relying too much on what QL says and making assumptions from it.

And that’s the problem right there. People like you think that the data QL gives you is good data, without understanding some of the assumptions that go into it. Same as with your optimum barrel time assumptions.