Loading 9mm for Accuracy/Precision

[Doublehelix]

I posted this on AR15.com and got a total of 1 response (a decent one, but only one). I was hoping for a more robust discussion, so I thought I would post it here as well and see where it goes:

-----------------------

There seems to be a TON of information and books around talking about how to make the most accurate *rifle* rounds, but not a lot about pistol rounds. I get why this is, but still would love to hear some suggestions on "taking the cartridge out of the equation" on accuracy/precision, and putting the onus on my skills and my pistol to get the smallest groups.

BULLETS:
I have read several posts around the 'Net discussing the "most accurate" 9mm bullets. I know that quality bullets make the most difference in rifle rounds, so it makes sense that it would be the same here.

I have always used round nose bullets in my handloads (Sierra FMJ, Berry's plated, Xtreme Plated, etc.). The plated are obviously for plinking.

I have seen some posts lately that indicate that there are a lot of folks that swear that JHP or SWC rounds are more accurate than round nose bullets (smaller groups, just to avoid the "define accurate" arguments, so maybe I should say "most precise").

Some guns prefer a certain bullet weight over others. How do you easily test for this?

Work up loads for 115gr., 124 gr. and 147gr.? Is this really an apples-to apples? Too many variables in my mind since you first need to find the most accurate load for each weight before you can compare different weights, right?

What have you found to be the most accurate?

BRASS & BRASS PREP:
I know it is not as important here compared to rifles, but I do notice a difference when I sort by headstamp (my pistols seem to prefer WIN brass).

Some other things that seem to be pretty universal: minimize flaring, and apply only enough crimp to remove the flare and hold the bullet tight enough to prevent setback.

I have tried things like primer pocket uniforming, flash hole deburring, etc., and there might be some improvement, but I am not sure that there is enough difference to warrant the amount of work involved.

Does anyone trim pistol rounds to length? I never have.

What other techniques do you perform on your brass that can add to accuracy? Sort by case mouth wall thickness? (Ugh!)

BULLET SEATING and OAL:
This seems to be a big one.

Concentricity and OAL are often discussed as factors that contribute to accuracy.

I use a Redding Competition Seating Die, followed by a Lee FCD, and I tend to just follow the loading data for OAL, and really don't experiment with this too much.

Am I missing an important technique to improve accuracy by not testing different seating depths? Didn't want to mess too much with internal pressures.

How are you guys determining OAL? Book values? Plunk testing? How much does this matter?


What else am I missing? Primer types? Primer seating? Moon phases?

Thanks in advance for contributing to this discussion.

 

[rskent]

I’m not generally an accuracy nut with a handgun, but here goes.

Bullets – The most accurate handgun loads I have used have been with XTP bullets.

I am sure there are better, cooler, slicker bullets than XTP’s, I have just not tried them.

I would guess that good bullets matter a lot.

Brass & brass prep – Very important in rifle, I have no idea in pistol.

Bullet seating and OAL – I have always seated handgun bullets with feeding in mind and

tend to run long. I have never tried to adjust for accuracy. I think most would tell you

that the Lee FCD is not gonna help with your accuracy.

 

[sbwaters]

With my .45 ACP 1911, I found what bullet my gun likes with an OAL that plunk-twisted close to the lands. It seems to be a Hornady 200 gr. HAP. I laddered several powders and found that Hodgdon’s TiteGroup was easy to measure, hard to double load, didn’t flash, and was relatively clean. Laddering the loads, according to loading manuals, from light to near max resulted in a load that met power factor, and produced the smallest group. That, it would seem to me, was a combination that fit the barrel’s natural harmonics.

I had standardized on Starline brass because it was -- don’t laugh -- easy to recognize when sorting brass from the range floor after shooting a round. It is also good quality and consistent. A recent thread on thehighroad has disabused me of the importance of standardizing case length because the taper crimp die was used only to remove the expander die’s bell. Still, I tend to load brass that is plus or minus .001 out of habit. Hope this helps.

 

[jell-dog]

Doublehelix,
Here is a thread that covers most of your questions:
THR Group Project - PISTOL - Advanced Reloading Concepts and Discussions
https://www.thehighroad.org/index.p...ed-reloading-concepts-and-discussions.778197/

I will share MY preferences with you below:

BULLETS: "What have you found to be the most accurate?"
Personally, in MY 9mm pistols,124gr/125gr bullets and 147gr bullets, plated or jacketed, are accurate enough for my shooting.
All pistols show some preference for one bullet profile over another, mine like flat nose or hollow point over round nose.

BRASS & BRASS PREP: "I know it is not as important here compared to rifles, but I do notice a difference when I sort by head-stamp (my pistols seem to prefer WIN brass).
Some other things that seem to be pretty universal: minimize flaring, and apply only enough crimp to remove the flare and hold the bullet tight enough to prevent setback."

Sorting by head-stamp does lead to more consistent groupings and bullet speed as you are minimizing the case volumes that different head-stamps may have.
You have also found a specific head-stamp (QUOTE: my pistols seem to prefer WIN brass) that work well in your pistol.

I tumble my brass in a mixture of walnut and corncob media with a cap full of New Finish Car Polish to clean.

I do not trim my pistol brass, but for (.380acp &) 9mm I sort by length after I resize and deprime my brass. 9mm is sorted like this: 0.950" Brass overall length (+/- 0.001") into one labeled container, 0.947" Brass overall length (+/- 0.001") into one labeled container and so on.
This does not take long at all and I can be assured of even belling and crimping of all the ammo made from each container of brass.
Of course, you don't have to limit your sorting to these measurements, this is just where I feel comfortable at.

Minimizing flaring is great for longevity of brass and maximizing neck tension, over-crimping will actually hurt your neck tension and deform your bullets.
For auto pistol calibers, use only enough crimp to remove the bell, after all, the cartridge head-spaces off of the mouth of the brass.

BULLET SEATING and OAL:
This thread works equally well for any auto "plunk" test and finding your "working OAL"
Using an auto pistol barrel find a MAX O.A.L with your bullet
https://www.thehighroad.org/index.p...rel-find-a-max-o-a-l-with-your-bullet.506678/

I hope this helps, sorry if I got a long winded

JD

 

[Ironicaintit]

I've found with my 9mm, that I get the best accuracy with JHPs. Specifically Hornadys XTP, followed very closely by Sierras JHP, followed by Speer.
I seem to shoot more accurately with 124s over 115s, but that could very well be in my head, too.

I bell as little as possible, and crimp only enough to iron out that bell. Ya really don't want to squeeze the bullet at all.
For OAL, I tend to just run with whatever the book says.
But, you could build batches at different lengths and see how they run in your setup.

If you really wanna chase down the accuracy of your gun, there's really only three things you need to remember.
Consistency, consistency, and consistency

 

[7mmb]

With handgun ammo seating depth isn't going to affect accuracy much. The bullet style and your pistol's chamber dimensions will dictate OAL. Seating the bullets straight will have a bigger effect. Your Redding competition seating die will go a long way toward seating them straight. A Lyman M die for expanding will help too. I use the M die for all handgun cartridges I reload (9mm, 45 Auto, 357 Mag, and 45 Colt) but only have Redding comp dies for the revolver cartridges. I noticed accuracy improvement just by going to the M die. The most accurate bullets in the world won't shoot straight if they're not seated straight.

 

[Blue68f100]

With handgun ammo seating depth isn't going to affect accuracy much. The bullet style and your pistol's chamber dimensions will dictate OAL. Seating the bullets straight will have a bigger effect. Your Redding competition seating die will go a long way toward seating them straight. A Lyman M die for expanding will help too. I use the M die for all handgun cartridges I reload (9mm, 45 Auto, 357 Mag, and 45 Colt) but only have Redding comp dies for the revolver cartridges. I noticed accuracy improvement just by going to the M die. The most accurate bullets in the world won't shoot straight if they're not seated straight.

Not true. I have one gun (BHP) that liked a specific length. When I changed my OAL I went from a 3" group down to 1.5". Of all the guns I have this is the only one that has showed great improvement by a change in OAL. Sorting brass will help a lot, then even sorting by length will improve it. Since most all handgun cartridges head spaces on the mouth of the cartridge, Longer cartridges will seal off quicker than one that is short. When the FP hits the primer it drives the cartridge forward till it stops either on the end of the chamber or the extractor holds it. Eliminating the movement will improve accuracy. Allows for a more consistent chamber pressure, less leakage. Most all pistol brass that I find is short in length. Some even below spec but we still use it. This degree of accuracy will probably only show up on the long range (50 yrds).

 

[Doublehelix]

Wow guys! Great responses, thanks! I knew I could count on THR to get a good discussion going!

Lots to think about and try, and some reading from those jell-dog links (thanks)...

 

[jwalts27]

I have found that sorting the brass by headstamp made a huge difference. When seating the bullet you can feel the difference in tension between Win, Fed, Blazer etc... Blazer seems to be the worst for me and when firing them for plinking purposes you can almost hear the difference in sound. Almost like your not getting a good seal in the chamber. I shot a perfect group the other day and my last round was one of these and it was a flier, ruined a perfectly good group.

 

[Doublehelix]

I shot a perfect group the other day and my last round was one of these and it was a flier, ruined a perfectly good group.

Haha! I love it! That has happened to me many times as well. I always blame the "sun in eyes" or some such issue!

 

[Sunray]

The 9mm has never been a target cartridge. Even Sierra says their Tournament Master bullets(start at 95 grains. That's a .380 bullet.) are made for reliable feeding before accuracy. Not many 9mm match grade/bullseye pistols made either. The shooting games don't require the same accuracy as bullseye shooting. Targets are much bigger(IPSC 'A' zone is ~ 6 x 12 inches. The '10' ring on an NRA 25 yard pistol target is 1.51".) and closer.
"...trim pistol rounds to length..." Pistol cases, not rounds, rarely stretch enough to need it. Sorting by brand or length doesn't make any difference either.
"...only three things you need..." Four, actually. You need the upper body tone required to hold the pistol still. Makes a huge difference. Small groups with a hand gun, any handgun, is more about the shooter than the pistol or the ammo. Olympic shooters spend as much time in the gym as they do on a range.
"...most all handgun cartridges head spaces on the mouth..." Only pistol cartridges(9mm, .45 ACP) headspace on the case mouth. Revolver cartridges(.38 Special, .357 Mag, .44 et al) headspace on the rim.

 

[Doublehelix]

Thanks Sunray. I get what you are saying, and I appreciate your comments.

Regardless, I want to make the most accurate 9mm rounds I can, even if they are not bullseye grade. Maybe I am chasing my tail, but it is good to hear what others have done to improve their 9mm accuracy.

 

[PO2Hammer]

When I loaded 9mm for accuracy I found bullet quality and bullet seating were the 2 big factors. Hornady 125 HAP and Winchester 147 JHP were my 2 faves. My first seating die was the Lee, that was terrible, the Redding Comp seat die is the way to go. I don't think the FCD is adding anything, I would ditch it in favor of a taper crimp without a crush ring.
Don't waste your time trimming brass. Sort yes, trim, no.

 

[rodregier]

125g HAP projectiles and WSF powder around 1100 ft/sec in a pistol brl is my accuracy combo in 9mmx19.
Bill Wilson sells a similar loading.
The HAP is an XTP without the expansion cuts. So the unit pricing is lower.