9mm workups with chrono

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All shot from 5" kimber 1911 same trip at indoor range. Labradar chronograph.

Factory pmc: 14rounds
Ave 1148fps
ES 42
SD 10.8
6 shot group .94" @25'

I shot some of these before throating the barrel and numbers were slightly better (33es)with more shots in the series. Could be variation in batches? Or bullets were up against the lands....maybe that could have helped the numbers?

I'm a little out of practice and not confident with my precision so only shot at 25 feet unsupported as that's the rule at the range. So groups may be irrelevant but I recorded them and put targets in my notebook. Need to talk to them about that....maybe look into a fixture to test accuracy and have it really mean something .

Tested 4 powders. All loaded to 1.125"+/-.001" with zero 115gr fmj, all pmc brass, cci primers, light Fcd crimp, charges weighed with hornady autocharge dispenser. All loads found in books or powder manufacturers websites but , don't go off my load info, find it yourself to be sure. Posting to share and see if others results are similar and see if others have come up with loads that outperform.

All tests are only 5 shot series, all velocities in FPS and all groups shot at 25'. Was already gonna take a long time and should narrow down what's worth exploring further.




Power pistol:

5.0
Ave 1067 fps
ES 47
SD18.1
Group 1.5"

5.3
Ave 1124
ES 34
SD 13.7
group .52" disregaurding called flyer. .98" with it. Looks promising. Think I'll be exploring around here.

5.6
Ave 1169
ES 67
SD 25.4
GROUP 1.5"

5.9
AVE 1227
ES 42
SD15
GROUP 1"

6.2
AVE 1297
ES 30
SD 11.6
GROUP 1.8

6.5
AVE 1327
ES 37
SD 16.4
GROUP 2.5"
Probably shouldn't have shot those last ones...but no pressure signs...definitely Hot.



LONGSHOT:

5.0
Ave 1057
Es 23
Sd 8.4
Group .7"
Pretty darn good but slow and higher charges hurt consistency. Think I'll make up more to see if it was a fluke.

5.2
Ave 1079
Es 58
Sd 20.8
Group 1.5"

5.4
Ave 1137
Es 77
SD 27.8
GROUP 1.3"

5.6
Ave 1176
ES 50
SD 20.1
GROUP 2"

5.8
AVE 1214
ES 45
SD 17.3
GROUP 2.6"



WIN231:

4.0
Ave 1008
Es 53
Sd 19.7
Group 2.2"
No slide hold open last round

4.2
Ave 1047
Es 82
Sd 30.4
Group 1.2"
No slide hold open last round

4.4
Ave 1090
Es 39
Sd 15.2
Group 1.5

4.6
Moved chrono accidentally setting up next series and recorded wife shooting 9mm in next lane. Need to load up some more of these. numbers seemed to be trending better and
grouped at .68"

4.8
Ave 1187
Es 67
Sd 24.5
Group .85"



AUTOCOMP:

4.8
ave 1049
Es 30
Sd 12.2
Group 1.1"

5.0
Ave 1083
Es 51
Sd 12.2
Group
.9"

5.2
Ave 1128
Es 68
Sd 30.2
Group 1.75"

5.4
Ave 1166
Es 48
Sd 18.3
Group 3"

5.6
Ave 1200
Es 75
Sd 30.3
Group 2.5"




Having the chrono is really neat to be able to see this stuff. Interesting how slow the bullets were moving and being at the bottom of load range with longshot and autocomp where they seemed to perform the best.
231 looked like it liked the top end charges to me, but didn't have any great numbers unless on the one that goofed on me. I had big spreads when I tested my .38 and .45 loads that I came up with using this powder before I got the chrono.
Power pistol was really surprising, both the velocities and where it seemed to perform the best at 5.3gr. Other than hornady starting at 4.8gr, all the others I saw started at 5.9gr...... which chronos almost 100fps faster than the factory rounds i tested. I noted that 5.6 gave a "factoryish recoil" in my notes, and that makes sense looking at velocities. Most calibers I've used power pistol in has seemed to give more perceived recoil than expected, now that I can measure velocity , seems there may be good reason for that.

James
 
Out performs in any way I guess. These were just the powders that were usable out of what I already had in my cabinet. Maybe someone has a load that uses less/cheaper powder that has great accuracy and/or ES numbers. Or really any thoughts about what someone loads and testing they have done. This is my first workups with a chrono. Got all this extra data now where before pretty much went by feel, funtion, accuracy, things I read online etc. Seems like only a few of these loadings did better than the cheap factory stuff i compared to in terms of accuracy and consistent velocities.

Also seems weird that my groups varried so much. Makes me want to blame myself , but had some pretty good ones with each powder. Had a few that out at 25yards would have been 2" or less. Definitely had some horrible ones.

James
 
Accuracy: That can depend on the gun and the bullet. If you're looking for the best accuracy you'll probably want to use FP or JHP bullets. RN bullets can be accurate but in my experience flat point and jacket hollow point bullets are more consistently accurate. Zero JHP bullets are superbly accurate, and their conical hollow point design outperforms their round nose hollow point designs, in my experience. The RMR FP Match Winners (any weight) are also superbly accurate. Hornady XTP and HAP bullets also do very well in my 9mm pistol (with a Kart barrel).

Your method of shooting offhand generally won't reveal what load is the most accurate. In fact, offhand is the worst way to test accuracy. I understand that you're limited to what your range allows, so you can't help that. Shooting off a bench rest is the minimum required method. What's best is shooting with the gun in a Ransom Rest to eliminate all human-induced error that can contribute to accuracy issues. I realize few people on the planet have that option. FWIW, I test accuracy with my guns in a Ransom Rest.

Several powders can produce excellent accuracy in the 9mm, Power Pistol being one of them. That will depend on who you ask and which powder people have tried. Other recommendations, based on my experience, are Silhouette, and Accurate #7. Win 231 seems to do well in my pistol, too. Other powders include Vit N340, N350, 3N37, 3N38.

Consistency: I've not found velocity consistency to predict accuracy. Not at all. It's only important if you're trying to shoot at a particular power factor for a sport where that is required. Otherwise, let the holes on the paper tell you what works best. And there is this: https://americanhandgunner.com/handguns/exclusive-consistent-velocity-accuracy/ That said, True Blue tends to produce consistent speeds and can be very accurate, but you'll notice in that link that True Blue did not produce better accuracy than the load with Power Pistol. But they were driving different bullets, too. So, you have to see what your gun likes.

If you want to be serious about testing accuracy and understand things like the limits of methods, like the number of rounds used to test accuracy, see this article: https://www.ssusa.org/articles/2019/9/25/accuracy-testing-shortcomings-of-the-five-shot-group/
 
[QUOTE="Suedenflames68, post: 11555694, member: 265877]
Also seems weird that my groups varried so much. Makes me want to blame myself , but had some pretty good ones with each powder. Had a few that out at 25yards would have been 2" or less. Definitely had some horrible ones.

[/QUOTE]

I should have been more clear about the accuracy thing. I would not worry about your accuracy results until you can test it properly. They might all shoot fabulous. Shooting offhand can give you a false impression that they are not accurate. Or vice versa. Proper methods matters here, and without that it's hard to draw any conclusions since you might come to the wrong conclusion. In the meantime you can chronograph stuff to check velocity and what feels right to you.
 
Thank you for taking the time to send that reply and the links to the articles. I had seen the first one before and found it somewhat depressing. The second one maybe even more so. Makes chasing accuracy and consistency seem unattainable. It's a huge stacking of variances that are still remaining after doing reasonably sized load tests coupled with large amounts of groups to get a more realistic idea of what the rounds will do. Really getting into probability statistics and mathematician stuff that makes my head hurt lol. Maybe my son in college could make sense of it haha.
I understand that comparing more rounds will get one closer to true average of them. Bigger seiries will have bigger ES numbers... well, maybe, probability and all that. And then you have the average of group sizes. Because even if one would shoot 50round groups it still wouldn't be the same each time. Plus variances of different guns/barrels, and throat wear, and climate etc.
Thought I'd be able to really dial in stuff with the chronograph, but like I've been hearing after getting it, the SDs dont = accuracy.
That first article did 15 round groups though and since there is variance in groups even with same ammo and second article says need very large groups to really I'm not sure. Wonder what 100+ round groups would look like with a powder that gives good SD ES numbers vs one with poor numbers with same bullet and similar average velocity.
Would definitely need a ransom rest or something. I've read that that can change it too tho because it doesnt move like the shooter would move.
I guess this is all why there is not just one answer to a perfect load for whatever caliber. Its variable ontop of average ontop of variable of averages and so on.
Power factor doesnt matter to me at this point but looking to get into next bullseye league at local range I think for something fun to do. I guess, without a ransom rest, a load that makes me say "I seem to shoot this well" may be about the best i can do.

James
 
Sorry , that may have got a little rambley... I tend to go over board on new stuff I find interesting. Haha.

James
 
There's no need to get depressed over accuracy testing, just be realistic. I think those articles point to how variable group sizes can be even when shooting under ideal conditions i.e. in a Ransom Rest, and the variation we can see even when shooting groups with the same ammo. This helps us to better understand what weight we can give our results.

Actually, the Ransom Rest does move under recoil similar to how humans do. The rocker arms pivots upward similar to how our wrist/arm pivots under recoil. But the IMPORTANT part is that it holds the gun in the same place every time AND it applies the same resistance to recoil every time. That's why it can also be used to 'measure' relative recoil. See this article: https://www.shootingtimes.com/editorial/measure-relative-handgun-recoil/99442
 
Here is a suggestion with the results you already have - Pick the load that gave you the best group, or the most acceptable group, and make up 20 - 50 more rounds. See if it's repeatable in your hands with your gun. If it is then you're done.
Honestly, if you listen to the internet, all your testing methods, no matter what they are, will be flawed.
 
Thought I'd be able to really dial in stuff with the chronograph, but like I've been hearing after getting it, the SDs dont = accuracy.
We should start a thread with all of us that thought a chrono was going to determine THE one load to rule them all! Been there, done that, but I still need and use my chrono for all my load work ups.
It’s good you did a calibration string with factory ammo first to insure the chrono is working. PMC ammo might just have larger variations than other factory ammo. I use Blazer and usually get an SD of 5-20 with a 5 shot group. I just make sure the velocity is where I expect it to be.
I’ll second the notion that off-hand testing isn’t ideal for relating group size to loads. Certainly not in my case, and for me I’m looking to meet certain power factors in addition to having acceptable loads. I use a cheap Caldwell plastic hand rest that helps take me out of the equation.
If you really want to talk permutation, start playing with COL! Good luck!
 
There's no need to get depressed over accuracy testing, just be realistic.

If you really want to talk permutation, start playing with COL!

Especially with 9mm. I don't consider 9mm to be a particularly accurate cartridge... when compared with others like .45ACP, but that is also based on the handguns I shoot them in. The 9mm, with it's small case capacity and high pressure, has always been a tricky cartridge... powder, bullet weight and shape, crimp, OAL... ALL of it seems to drastically change the cartridge, not only in regards to accuracy, but pressure and other characteristics, more so than any other cartridge I've ever loaded for.
 
At least one gunsmith who makes custom 1911s for Bullseye competition, say the 9mm and 38 Super are more accurate than the 45.

https://chamberscustom.com/about-us/

And that is very likely... you will note I tempered my comment that it was based on the pistols I shoot; even my old HiPower, which was a decent pistol, didn't seem to have the accuracy potential my .45's do. A pistol built to compete can be accurate with, very likely, any cartridge.
 
I guess I've found that the most accurate load off a rest isn't the most accurate load for the way I typically shoot. They are certainly in the same ballpark, but I think it's important to look at the system as a whole, and that includes the shooter. You isolate various components to find strengths and weaknesses, but everything still has to work together as a functional system.

I would be happy with any of those 1" groups at 25'. Nice shooting.
 
We should start a thread with all of us that thought a chrono was going to determine THE one load to rule them all!

Haha yup that would be good. Still a great tool to have. Love knowing the numbers...just doesnt apparently accomplish all the goals I thought it would for me. I research most everything, drives my wife crazy, and sometimes just dont even know what to be looking for till actually into something new.
With the rules at the range I'll just make up larger batches, as suggested, of the apparent performers in power pistol , w231, and longshot for a somewhat lighter load and see if they still look as good as they did in the 5 round tests. Got 2000 of these bullets left ,but I'll probably try something new when I run out. Rmr stuff seems to be popular, looks good and is less expensive.

I wonder at what point ES does become significant. My 38spec and 45acp loads I came up with prior to chrono with 231 have huge spreads ,100+, and they are already pretty slow. Old range allowed bags, had stools, let me raid the brass buckets within reason, and was cheap. $99 yearly membership, man I miss that range. Was going every week and was a decent shot back when I worked those up for accuracy shooting off bags. Was really suprised at the bad numbers when I chronoed them. Been a few years since I've been shooting regularly, just going every once in a while and not loading much till the last few months when I suddenly had more free time.

James
 
Well tested larger batches of the loads that looked like winners.

W231 4.6gr loads for 25 rounds
Average 1163 fps
ES 103
SD 26


Longshot 5.0gr 25 rounds
Average 1073
ES 99
SD 25.9
The really good consistency numbers went away with bigger sample.

Power pistol 5.3gr 25 rounds
Average 1140 fps
ES 66
SD 20.2

Shot 17 round groups at 25' for each and they were all about 2". Then shot 8 round groups at 50' and they were all right at 3". Longshot was the worst at 25' @2.3" and best at 50'@2.5". So yep, these groups are just my own shooting variances.

Just gonna load something. Either finish off some powder or use what I got most of. Lol

James
 
Longshot 5.0gr 25 rounds
Average 1073
ES 99
SD 25.9
The really good consistency numbers went away with bigger sample.
Normally Longshot is happiest on the higher side of it's charge range even though your first test didn't show that.
I used Longshot in 9mm when it was all I could get but unless you are after the velocity it offers on top there are better choices for 9mm IMO
(BE86 or Silhouette are my choices for full power stuff, I also use WSF for full power stuff but it givesup a little velocity to the first two)
 
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I think I've heard that said before in regards to the longshot in upper ranges in 9mm. I saw a can of BE86 at the store the other day , should have bought it but thought I had more power pistol than I do...down to a pound or so. Loading up some more in longshot cause I have a half full jug and only regularly use it for 10mm. It's weird, nothing I've tried so far other than my 10mm load have giving me anything good as far as consistency numbers. Kinda want to try that true blue powder in the article just so I can see it lol. Those articles really make it seem like powder choices dont even matter if different velocities dont affect accuracy. Guess it would matter for PF concerns.

James
 
I can take two powers say X and Y and load to the same vel and my gun just happens to like on better than the other.
On rare occasions my different 9mm's will sometimes even sort of agree on what they like best, but all seem to prefer something.
Sometimes the one that looks best.. smaller ES and SD does not shoot as well as a load that may have a larger ES and SD.
So while good numbers are nice in pistol I don't sweat the #s a lot if they are reasonable.
Holes on paper are what matter, and since I don't shoot from a rest if the load is capable of shooting as good as I can I am in business.
Unless you are weighing every charge a powder that meters better might give a smaller ES and SD but just not shoot as well.
I have pretty much decided to let my pistol tell me what it likes, it knows what it likes and there is no arguing with it sort of like SHMBO:D
 
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