9 mm reloads - theory (How to...)

Hello,
I am new to this forum. I've been reloading for three years now. Only 9x19. I am from Europe, where the gun culture is very weak compared to the USA, so even the valuable info about making accurate handload cannot be found easily. I have many questions about reloading for accuracy and I don't want to try to reinvent the wheel. You guys have been there, done that. So I would really appreciate, if you would be so kind and share your gained knowledge. The components which I can buy here in Europe are different from what you guys mainly use in the USA, so I am looking for common advice rather then exact recipe for 9 mm accurate handload.
I have access to Ransom Rest to test my reloads (we bought one together a month ago with my friend to get our reloading to next level), but I haven't been able to make any really good load yet.

1) How much does primer effect accuracy? (I used to use sellier bellot primers and the velocity was much more consistent that with Fiocchi which I use now, because the SB primers were for a long time out of stock everywhere here; the velocity spread is for about 50% higher with Fiocchi) Do you have some experience that with all the other components being the same, the different primer changed significantly your groups?
2) I slugged the bore of my barrels. My match barrel seems to have 0.3516" bore diameter. I used to reload .356 bullets for my pistols with OEM barrels and I didn't need to crimp a lot because the chamber was a bit loose. My new IGB barrel has tighter chamber so I need to crimp .356 bullet to .354 to be able to get the cartridge to the chamber. Should I rather use .355 bullets to avoid crimping? How much crimping is OK?
3) Stabilization of the bullet. Can you approve that 1:16" twist is better for accuracy than 1:10" (Don Miller's twist rule)?
4) Theory says that COL should be as long as possible but not too much to get in contact with the riffling. Does it work all the time? Are your most accurate loads the ones with the longest COL as possible?
5) The shape of the bullet - FP vs RN. Does it matter? Is one of them better choice for accurate match ammo?

Thank you very much.

I will do what I can.

Primers do not chamge much, but keeping with the same brand will help. Consistancy.

.3516 Bore or Groove? Should be .355". The only way to be sure is try both .355 and .356 to see what is more accurate.

Same for OAL. Try lengths in .010" increments. When you find the two best, go inbetween those in .002" increments. Each bullet will have its own best OAL. Some guns show a preference after a while.

The best shape of bullet is HP. Its most stable spinning. Again each gun has its own prefrence. 9mm ia a little different than 38 or 45. They like to go faster for accuraacy.

Its great you have a ransom rest. I do not have access to one or a place to use one if I bought it. You can test bullet length, style, and powder charge all you want. I am stuck using a pistol rest and my hands.

I do have my Dan Wesson PM-9 shooting just under 1" groups at 25 yards. I can't test at 50 yards till it warms up a little more. This peticular gun likes max charges. I can get away with a little less velocity with a max charge of a faster powder. Its a 16" twist. In the winter we shoot at 50 feet indoors.
After a while of shooting you will see trends of your gun.

Good luck. I hope others come along and add or correct this.

David

A lot of pistol ammunition that is used in the USA for target purposes, is lower pressure ammunition, such as the .45 acp and the .38 Special.  The 9mm is much higher pressure.  

A lot of European 9mm barrels I have seen, have groove diameters that are about .3575".  This larger groove diameter seems to be intended to allow some gas to leak around the bullet at peak pressure, lowering that peak pressure some.  A lot of USA shooters like to use Lead bullets for target shooting, and a Lead bullet being smaller than groove diameter would result in tremendous Lead fouling.

All good points mentioned above.  Best accuracy is with jacketed bullets, and hollow point does seem to be the most accurate.  They have a longer bearing surface in contact with the barrel.  So with that logic, the flat point will likely, but not always produce better accuracy than the round nose.  Lead bullets can do OK, but the high pressure 9mm will likely produce barrel leading.  Lead bullets don't do well in polygonal rifled barrels such as Glock.  The slower the barrel twist, the faster the bullet needs to travel to obtain good accuracy, such as the 1:32 inch twist, needing at least 1100 fps.  The faster twist (1:10" or 1:16") are good with the heavier bullets like the 124 and 147 grain.  I've had great results with the 1:16" at moderate velocities using a 115 grain hollow point. 
COL in the 9mm is more critical.  Every gun is an individual, but generally .005" to .020" before engaging the rifling is a good place to start. 
Don't worry about your primers. 80% of your ammo's accuracy is in the bullet, 15% is in your powder charge and 5% is in the primer and case.  But since the 9mm operates at twice the pressure of other pistol calibers, it is best to keep the primer and case of the same manufacture for consistency,

just a suggestion...

Search found 116 matches for 9mm loads

using search  enter +9mm +loads

You'll get a lot of replies and most opinions. Most have their favorites. There a lot of variables that effect accuracy. I have a 9mm 1911 I built myself. I used a KKM barrel with a 1:32 twist. This is the same twist the Army Marksmanship Unit used and I think still does. I load my ammo to factory speeds. I find it shoots @ 1 to 2 inches at 50 yds.. You'll just have to experiment until you find a load that suits your gun. FYI I shoot lead not jacketed.

Larry2520 wrote:You'll get a lot of replies and most opinions. Most have their favorites. There a lot of variables that effect accuracy. I have a 9mm 1911 I built myself. I used a KKM barrel with a 1:32 twist. This is the same twist the Army Marksmanship Unit used and I think still does. I load my ammo to factory speeds. I find it shoots @ 1 to 2 inches at 50 yds.. You'll just have to experiment until you find a load that suits your gun. FYI I shoot lead not jacketed.

Care to share your load data, please?

tfk asked for guidence, not specific recipes. Working up a load for your specific firearm will get best results.
I am quite sure my loads will not work in your gun. My OAL is just what fits in the magazine. Max 1.169". I have deep throats in both of my 1911 9mm. The are both less than 2 years old. Luckily both shoot one of my pet loads for target.

Expermenting is part of the fun and part of getting to know your gun better. Sort of like bonding. You can try diferent bullets, shapes, weights and OAL. You can try different velocities and different powders until you find what seems to work best.

With a 38, Ican tell you 2.8 grains of bullseye with a HBWC seated flush will be a good load. 9mm is not that easy.

Enjoy the hunt
David

David R wrote:tfk asked for guidence, not specific recipes.   Working up a load for your specific firearm will get best results.  
I am quite sure my loads will not work in your gun.   My OAL is just what fits in the magazine.   Max 1.169".  I have deep throats in both of my 1911 9mm.  The are both less than 2 years old.  Luckily both shoot one of my pet loads for target.

Expermenting is part of the fun and part of getting to know your gun better.  Sort of like bonding.    You can try diferent bullets, shapes, weights and OAL.  You can try different velocities and different powders until you find what seems to work best.

With a 38, Ican tell you 2.8 grains of bullseye with a HBWC seated flush will be a good load.    9mm is not that easy.

Enjoy the hunt
David

I suspect this was not directed to me because I'm not tfk and you're not Larry2520.

I already understand load development, thanks, which is why I asked because the bullet and powder selected are the most important components (especially the bullet) to accuracy and would love to save time and money in working out accurate loads. Experimenting can be fun but it's also very expensive and very time consuming. Knowing what works for one person can direct testing efforts and can save lots of time and money for people developing their own loads.

I am especially interested in Larry2520's bullet because it's lead. I'll be working with more of those in the future.  Larry2520, could you please share your load data? That would be awesome. I suspect other readers of this thread might also be curious. Thanks.

S148 Iapologize if I offended you. Not my goal.

David

David R wrote:S148  I apologize if I offended  you.  Not my goal.

David

No problem.

Load data from someone else is always good. Sometimes it has led to finding something accurate, and sometimes not. In some instances I already knew that the bullet someone else used won't shoot well in my gun. I'm just trying to narrow down the testing parameter because there are a gazillion different lead bullets, and the last time I looked they weren't giving them away. It's also a problem with some lead bullets that they only sell them in 500 or 1,000 count quantities. Costs get outrageous very quickly.

Thanks for all the advice. And yes, I don't want the recipe, because I am pretty sure it won't work the same with my barrel. I am most interested in reloading hypotheses proved by someone's own experience. I think I've already use high quality bullets. The weight of the bullets is 123,00 +- 0,1gr and they are all exactly .356 diameter and have regular shape. I've read that HP are the best and I think that the main reason is the one meant by oldsalt444, that it's because of the length of the bullet and so longer bearing surface in contact with the barrel and as David R also meant that the HP are better stabilized which can be also due to their lenghts (Miller twist formula). This can be somehow identified in ammo testing made by Ammo Squared channel on YouTube, where the ammo with the lowest maximum spread and mean radius are the long ones, no matter if it's 147 gr bullet or 115 gr HP. Ammo with regular 115 gr or 124 gr FMJ bullets can be found at the bottom of the summary sheet. The only exception there, that I found, was Speer Lawman 115gr TMJ, which scored quite good compared to the other types of tested ammo.

Oh, and I can make a small information contribution to this thread. 

Q#5. Flat nose bullets tend to shoot more accurately than round nose bullets. That was examined in the article below, with 9mm factory ammo, and the author used a statistical test for that comparison.  But I've also found that to be true with handloads as well.  

https://www.ssusa.org/articles/2019/1/18/38-different-9mm-loads

tfk, if you have access to PPU 115 grain JHP bullets, they might be good ones to try. They seem to shoot well in several of my 9mm pistols, based on results with factory ammo.

tfk, where is the summary sheet you mentioned?  Do you have a direct link to it?

Thanks.

S148, great info. Thank you. I'll have a look at it.
What about the OAL? Is there any consensus about the optimal lenght of the cartridge - or I shoul maybe say optimal distance from the point where bullet already touch the rifling? Has anyone of you experience a really accurate load which was quite short? I read often that the OAL should be as long as possible but still not touching the rifling. Because the shape of the bullets will never be exactly the same and the lenght of the brass may differ a little bit also, it is said that it should be 0,005-0,015" shorter than the OAL which is already touching the rifling to avoid that some cartridges will touch the rifling and the initial pressure will differ more than when none of the cartridges does it. However it is said that big jump to rifling is not good for accuracy. What's your experience? Can you prove it as true? Are you making your match ammo that way?

It's not official, I made the list from the videos I've watched on their channel. There are not all the tests they have made by now. They have some new tests, so the list could be twice as long, but even now the data are interesting. There are three sheets in the file, 80% group, 90% group and 100% group. The 100% group is ifnluenced by wrong operation with Ransom Rest and the group is enlarged by 1st flyer which was caused by droping the slide and different lockup of the barrel compared to other shots.... so it's better to explore the data in 90% group.
docs.google.com/spreadsheets/d/1yAxPivAI7vnm2-dvVmSOHc_BotF9LHh1Q5M6lQTG6wo/edit?usp=sharing
If anyone would like to edit the file and add some other ammo data from their youtube channel, feel free to edit.

btw: the best result was achieved with the ammo with the biggest velocity spread (64 fps) which I personally find to be very interesting.

tfk wrote: 

btw: the best result was achieved with the ammo with the biggest velocity spread (64 fps) which I personally find to be very interesting.

Thanks for that link.

Yeah, there does not appear to be a correlation between velocity extreme spread and accuracy for the typical handgun at typical handgun distance. That was tested here: 

https://americanhandgunner.com/handguns/exclusive-consistent-velocity-accuracy

Very impressive article. Thank you very much. I knew it was a good idea to sign up to this forum. So much great information.

Missouri Bullet company has sample packs of 100 cast bullets. HI TEK coated or conventional lube.
David

David R wrote:Missouri Bullet company has sample packs of 100 cast bullets.  HI TEK coated or conventional lube.
David

Yup, I know.

But some bullets are only sold in greater quantities, like Speer and Lapua 32 caliber wadcutters which I've only seen in 1,000 count boxes. I dislike being forced to pay $130+ just to "try out" the Lapua bullets.

The bullet is the most important variable followed by the case.  

HP bullets are indeed the most precise because with HP, the opening to the lead core is at the front and so there is a closed rear part (unlike round nose which are closed at the front and open at the back) - I am talking about jacked bullets.

The reason having a closed rear is important is because this allows the manufacturer to build a much more consistent bullet base.  That is of critical importance because the last thing that is in contact with your barrel's crown when the bullet is fired is the base of the bullet.

If the base is even slightly uneven, one part of the base will leave the crown of the barrel first which allows the gas from the barrel to escape from that area, THAT will push the bullet slightly sideways which of course will alter the direction of the bullet.  Imagine different bullet with leaks in different area of the base and the bullet being pushed sideways slightly in different directions - THAT is why a group is not tight.

I've been lurking and studying this forum for quite some time and it's time I participated.

I load and shoot 9mm cast.
My most accurate bullet is the 128gr SWC from a NOE mold. It has a long body and a short nose. Seated till the shoulder engages the rifling than back off .025" for reliable chambering. This gives me an OAL of 1.050". The gun is a CZ with a shorter throat than many others.
I cast the bullet with 5-1 WW lead and 40/60 bar solder. Water quenched. Sized and lubed at .359".
Cases are sized and de-primed normally.
***I inside size with a 38 special die which is approx. .002" larger than 9mm.***
Bell is large to not scrape the bullet in seating.
Dillon powder dispenser with normal 9mm powder funnel.
Redding taper crimp die. Long and smooth bell removal.
Chamber check all rounds. Much closer tolerances in chamber.
Make sure there is no lead or lube buildup at case mouth.
A cloth damp with mineral spirits to wipe off any errant bullet lube.

9x19
Groove diameter: this can range from 0.354 to 0.362". For modern barrels, use at least a 0.360" lead slug to determine actual groove diameter.
Use lead bullets at least 0.001" over groove diameter for 9-13 BHN bullets and 0.002" over for 18-22 BHN bullets.
Even with jacketed, I find.38 bullets are generally better than 9mm bullets. Check SAAMI--barrel dimensions are the same.
Near max pressure is usually best.
JHP or L-SWC are usually best.
With lead bullets, you'll need a larger expander to prevent lead bullets being swaged down.
You need a get seating plug that really fits to have any hope of coaxial seating.
Power Pistol has been best powder I have found.
For standard barrel, you need to test 115, 121, 125, and 147gn bullets to see what your gun likes.
My dream is an ACCU Shadow from CZC.

noylj wrote:9x19
Groove diameter: this can range from 0.354 to 0.362". For modern barrels, use at least a 0.360" lead slug to determine actual groove diameter.
Use lead bullets at least 0.001" over groove diameter for 9-13 BHN bullets and 0.002" over for 18-22 BHN bullets.
Even with jacketed, I find.38 bullets are generally better than 9mm bullets. Check SAAMI--barrel dimensions are the same.
Near max pressure is usually best.
JHP or L-SWC are usually best.
With lead bullets, you'll need a larger expander to prevent lead bullets being swaged down.
You need a get seating plug that really fits to have any hope of coaxial seating.
Power Pistol has been best powder I have found.
For standard barrel, you need to test 115, 121, 125, and 147gn bullets to see what your gun likes.
My dream is an ACCU Shadow from CZC.

I can add some info to help, and BTW noyli I have an ACCU shadow from CZC along with a TSO, and a Ransom rest. When it comes to accuracy in a 9mm the most accurate loads tested were JHP' with slower powders, N330, N340, and Power Pistol. Case brand makes a big difference so sort brass and use same brand, I prefer Win, Fed, Rem. Throw away CBC. I generally load for my shortest lead barrel which is my CZ's. I prefer JHP's, and Flat Point Hi-Tek coated bullets in 125,135,and 147 gr. I do use a 160 gr round nose Hi-Tek sized .358 in my 929 revolver, that was got the best accuracy, and  .356 coated bullets, and .355 JHP's in my Auto's. Primers make a difference in standard deviation so find a good one and stick with it. S&B, Federal, CCI are great, Winchester, Fiocchi, Remington are ok. I look at the max load in a couple of manuals and subtract 10% as my starting point. I come up in .2 gr increments till I hit Max, and depending on my results may go over by .2-.4 if no pressure signs are observed. As far as OAL use a Hornady OAL tool and modified a 9mm case to fit the thread (5/16 x36) then measure to the rifling, then back off .015" depending on the lead of the barrel, for example my STI's and EAA have long leads so I start at 1.150" and work down in .010" increments after I find the most accurate load with powder charge. For example if I started at 3.4,3.6,3.8,4.0,4.2 and best accuracy was achieved at 3.8, I then start reducing OAL in .010 increments to see if accuracy improves. I find that every bullet has a sweet spot. For me Precision Delta and Montana Gold 124 JHP' at 1.080-1.085 was best for those bullet. Zero 125 JHP's liked 1.100. My initial testing is at 25 yds from the Ransom Rest in 10 shot groups. If I bench rest I shoot 3 five shot groups. I think when my new inserts arrive for my G19 Gen5 and my CZ TSO I will change my method with the Ransom rest and shoot 30 shot groups from now on. I did 3 five shot averages for years because that's how it was done in magazine articles years ago. If anyone is interested I have all my load data in a zip format on Brian Enos' forum under my name Darrell, just do a search, I uploaded the latest revision last week. Also 9mm likes to go fast to get the most accurate groups. Crimp is important too, but I found that if I crimp .377-.378" it work for all bullets Jacketed and Coated.

tfk,
Take a look here https://czfirearms.us/index.php?topic=100352.0
Very useful information.