Lousy & Illogical statistics but GREAT 5-shot pistol groups. Go figure . . .

[fxvr5]

Brad Miller (PhD) has done excellent work with higher powered 9mm loads within the past year, but unfortunately, this specific article does not show ammunition accuracy representative of his normal work, because he apparently was limited in his readily available choice of pistol that would handle 9 Major loads.

Or, maybe because that article was 9 Major in a short barrel, and the barrel in the Glock was ~4.6", which is less than the often used 5" or longer barrels used in Open Division IPSC guns. And Glocks are not known for their match quality accuracy, even with a non-glock barrel.

If you Google his other articles on higher velocity 9mm loads (NOT just "9 Major) in "Shooting Times" magazine, you'll find some amazingly accurate higher velocity loads.

i.e. this article: https://www.shootingtimes.com/editorial/fast-9mm-loads/388612

 

[kidneyboy]

Lousy & Illogical statistics but GREAT 5-shot pistol groups. Go figure . . .

You are about to see some pretty lousy and sometimes seemingly illogical statistics for the ammunition I loaded and fired recently. But three 5-shot groups qualify as probably “great”, considering my mediocre talents as a shooter and my aging eyesight.

I am scratching my head trying to figure out why the groups are so good when the individual statistics on the ammo are either mediocre or actually lousy.


Some background:

I have been working to develop a 9mm 115g load for my SIG P210 pistol. I load on a Dillon XL750. I recently added Armanov bolted-in toolheads and free fooating die rings. I also replaced the Dillon bullet seating die with a 9mm Redding Competition Bullet Seating Die. These changes were to address an inconsistent Cartridge Overall Length (COAL) problem that I thought might be increasing group sizes.


The load under development is:

9mm Luger

Using new, and then pre-fired by me Hornady cases

115g Hornady HAP bullets (jacketed truncated cone with hollowpoint), which were designed as XTP bullets withOUT the expansion cuts, for use in Action Pistol competition shooting

Federal Gold Medal Small Pistol primers

8.0 grains of Vihtavouri 3N38 powder, which is a slow burning powder, again targeted at Action Pistol shooting competitiob, where the slow burn rate supports high velocities and has sufficient post-barrel residual pressure to operate a compensator to reduce recoil

The objectives of the load include high accuracy, muzzle velocity of around 1300 fps, manageable recoil, and lower peak pressures than you might expect due to the slow powder burn rate. All 3 objectives have apparently been met, but the load exhibits some statistics that leave me wondering why it works so well despite those statistics.


The Pistol:

The pistol is a brand new SIG P210A Target model, that before yesterday’s shooting session had only 240 rounds fired through it.

Here are the 3 best targets from a shooting session yesterday to test multiple different COALs. Remember, these are 5-shot groups, fired at a verified 25 yards, from a SIG P210A Target model pistol:


View attachment 985796



View attachment 985797



View attachment 985798


I think we cna all agree that while these are by no means “perfect” groups, most pistol shooters would be happy with them. And note that they were fired at the local outdoor range, in 0 to 4 degree C weather (32 to 40 degrees F), using a 6” x 6” x 6” carpeted cube as a rest, and I am 70 years of age, have had cataract laser surgery, and wear progressive bifocal eyeglasses. And yes, open sights.


The Analytical Excel Worksheet:

I had prepared an Excel worksheet that documents the 35 prepared cartridges, plus 5 cartridges that were used for sight adjustment beforehand. This Excel worksheet was filled in gradually, before, during, and after firing the rounds, as the information for the worksheet fields became available.

The worksheet image included here is very hard to read, because Excel does not support exporting as a jpg file. So I had to zoom OUT in the Excel view, snap a desktop image, and then import that image into the Apple Photos program. There, I trimmed it, optically enhanced it, and saved it as a jpg that can be printed on an 8.5 x 11” sheet of paper and that could be imported into this forum. If you unexpectedly find yourself mesmerized by the patterns, unexpected results, and apparent contradictions in it, and want to look at it more closely, you might find it best to print it out on paper where it iS legible.

Here’s the worksheet image:


View attachment 985799



Here is how to read the worksheet (if you actually want to do so) taking it one column at a time:


Target no: Each target sheet contains one 5-shot group, and is labeled as either 1 through 7, or as “Sighting 4”. Sighting 4 is the 4th group fired in the process of adjusting the sights to shoot a bit below the point of aim, which is the bottom point of the black triangle. I wanted to shoot below that point so that any shot holes would not obscure the aimpoint.

Round no.: This shows the sequence in which 5 x 7 = 35 rounds were actually made, measured, and then fired. They were fired as 5 shots into each of 7 targets. In addition, the 5 shot numbers for the “Sighting 4” target are shown as being the 16th through 20th shots fired at sighting targets. These shots do NOT have detailed measurements like the other 35 shots do because they were not part of the control group.

Crimp diameter: This is simply the measured crimp diameter of each round.

COAL to Tip of Bullet: This is the COAL for each round, measured simply as the distance from base of cartridge to tip of the Hornady HAP 115g hollow point bullet.

Base to .338 Gage: This is the supposedly more accurate way to measure cartridge length. Coal to Tip of Bullet is usually inaccurate with most jacketed bullets, as bullet manufacturers apparently are able to control bullet ogive dimensions and shank dimensions much better than they are able to control tip dimensions. I expected these to be much more consistant than the base ot tip of bullet dimensions, but was surprised . . . ! To measure this, I used a Hornady Bullet Comparator with my digital caliper. Hornady does not offer a 9mm (.355”) insert for the comparator, as the comparator was designed to measure rifle bullets, not pistol bullets. But that does not matter. To assess cartridge OAL consistency, the measurement can be taken from the cartrudge base to ANYWHERE on the ogive, as long as you always measure to the same point on the ogive (i.e. to the same ogive diameter). This is actually BETTER than trying to measure to the point where the bullet shank stops and the ogive starts, as there is obviously a transition zone there for any manufactured bullet, and therefore a potential for measuring error. So, I used the .338” diameter insert for measuring each cartridge. Ideally, each cartridge would have the exact same base to.338 gage measurement.

Why is this measurement “better’ than the Base to Tip measurement? Two reasons:

1.It should be more accurate, since ogive dimensions are betetr controlled by bullet manufacturers than tip dimensions are

2.We really don’t care where the tip ends up when the round is chambered, as long as the cartridge feeds through the magazine and can be chambered. But we are very concerned about the measurement from base to ogive, as it is the point at which the shank and ogive meet that first touches the rifling when the cartridge is fired. And we want to control that point, because it

1. sets the amount of “jump” that the bullet has to make before it hits the rifling and pressure increases as a result, and
2. affects the size of the “combustion chamber” in which the powder is ignited. The deeper the bullet is into the case, the higher the peak pressure generated upon ignition.

Muzzle velocity: This was the actual bullet muzzle velocity, as measured by the super accurate Labradar, when each cartridge was actually fired. Big surprises here.

COAL to Tip Std Dev for 5 prior: This is the standard deviation in COAL as measured by the “bullet tip” method in the 5 preceding rounds.

Base to .338 gage Std Dev for 5 prior: This column shows the standard deviation in Base-to-.338 gage, as measured by THAT method, in the 5 preceding rounds.

% Gage versus COAL Variance: This expresses, for each group of the 5 prior rounds (i.e. all the rounds included in that specific target no.) the magnitude of the length variance as expressed by the “.338 Gage” method versus the “COAL to Tip” method. Based on the bullet manufacturer assertion that ogive dimensions are much better controlled than tip dimensions, we epxect this ratio to be less than 100%. If it is more than 100%, it means that the standard deviation for the ogive based measurements was WORSE than for the TIP based measurments. That should not happen (But it did . . . )

Wow. I hope you don't make the rest of your life this complicated. I don't mean that in a demeaning sort of way. Shooting pistols accurately is subject to a lot of vagueries, like when was your last cup of coffee or do you have gas or something.
Here is my 2cents - find a bullet your barrel likes then find a powder your bullet likes. It's not complicated and doesn't really need charts or anything but it's time proven and effective.

 

[JimGnitecki]

Regardless the size of the threads, the distance it moves is just that.
What locks the Redding also locks the RCBS, friction.
If one can’t tighten it without movement, one can’t tighten the Redding, without movement.

All this is lost within the pulse in your wrist...

I changed over from the Redding to the Dillon tonight so I could try the custom seating insert for the Dillon. Trust me: There is NO comparison between the ease of setting up the Redding (easy) and the Dillon (ridiculously iterative and time consuming).

Jim G

 

[JimGnitecki]

It WAS the seating die insert!

I removed the Redding seating die and installed the Dillon seating die, BUT I did NOT use the Dillon seating insert, but rather installed the customized seating insert that mr U.S. friend on the forum had made for me.

After doing so, I made 25 cartridges, and here are the COAL to Tip and Base to .338 Gage results:




Note the following:


1. Both the COAL to Tip and the Base to Ogive Extreme Spread variances are smaller now.

2. The Base to ogive Extreme Spread variances are now smaller than the Coal to Tip variances.

3. The average Extreme Spread in COAL to Tip for the 5 groups of 5 cartridges each is now .0022"

4. The average extreme spread in Base to ,338 gage for the 5 groups of 5 cartridges each is now .0017".

Each of these outcomes is a sensible outcome:

Both the COAL to Tip and the Base to Ogive Extreme Spread variances are smaller now because the customized insert for the Dillon die was made specifically to grab the ogive of the bullet, and NOT the tip. Since the ogive is far more consistent on any bullet than the tip height, the variance in OAL is now reduced.

The Base to ogive Extreme Spread variances are now smaller than the Coal to Tip variances, which is what we EXPECT to see, since the ogive is far more consistent on any bullet than the tip height.

The average Extreme Spread for both COAL to Tip and Base to .338 gage for the 5 groups of 5 cartridges each is now reduced to more like what I had hoped for in setting up my Dillon XL750 progressive loading press, and the Base to .338 Gage variance approaches the precision of loading on single stage equipment.

But i am not done yet.

My local gunsmith has a lathe, AND even has access to a buddy's CNC machining center. I asked him to bore out the seating insert that came with the Redding die, so that it too would stop catching the tip of the bullet and instead seat via the ogive.

Boring that Redding insert out requires precision machinery, as the OD of the insert is only .3580", and I want the center "pass through hole" bored out to .2500". That leaves only a .054" wall thickness. So, I need the boring operation to be pretty much perfectly centered to avoid asymmetric loading of the insert during the vertical pressure of the seating operation. Boring out that passthrough hole will ensure that the bullet tip can go right past the narrowing cone in the die that is supposed to catch the ogve, and not the tip.

If the customized Dillon insert is working so well, why bother to modify the Redding insert? Because the Redding die offers the micrometer feature to easily, closely, and much more predictably and precisely control the exact base-to-.338 Gage distance. The Dillon die is a major pain to adjust.

Having the ability to adjust the base to .338 Gage measurement so closely on the Redding die will encourage me to easily and quickly try different amounts of bullet "jump" distance to the rifling.

One of the advantages of being able to do that is that I can then follow the Berger Bullets advice to load as long as possible consistent with good accuracy. That will allow me to increase the size of the "combustion chamber" (the volume inside the case underneath the seated bullet). THAT will allow me to either (a) lower the peak pressure, or (b) add more powder without increasing peak pressure, and thus gain a bit more velocity. More velocity in a handgun cartridge is a good thing for stopping power, as long as it does not reduce accuracy, as stopping power is proportional to energy which is proportional to velocity SQUARED. So for example, a 3% increase in velocity gives you 6.1% more energy. If I can get 6.1% more energy withOUT increasing peak pressure, that's a freebie win.

Jim G

 

[Demi-human]

as stopping power is proportional to energy which is proportional to velocity SQUARED. So for example, a 3% increase in velocity gives you 6.1% more energy.

So a 22 Hornet has more stopping power, 729 ft/lbs, than a 45 Auto, 430ft/lbs?
I know which one I would use for defense, it isn’t a 22...

I have not seen measuring to the fourth decimal for CBTO in pistols.
I didn’t realize Berger made pistol bullets...

How did you reach an ES of .0022 and .0017 when all your measurements end in zero or five?


All this math is fine, but math is a tool. No one wants to look at gasoline, they want to look at the Ferrari.

To that, how does it shoot now?

 

[rfwobbly]

If the customized Dillon insert is working so well, why bother to modify the Redding insert? Because the Redding die offers the micrometer feature to easily, closely, and much more predictably and precisely. The Dillon die is a major pain to adjust.

The Dillon seating die is strange in that, unlike other dies, you need to move the whole die up/down to adjust cartridge OAL. Not simply the internal stem.

Here's a tip that might help in that area.... Take the fat o-ring off a Lee lock ring (or any similar sized o-ring) and place it between the Dillon tool head and the seating die's lock ring. Run the lock ring down to "snug" and leave it. This allows easy adjustment of the seating die body without disturbing anything else. The o-ring absorbs all the vibration, and the die setting won't ever change until the next twist of the die. In this way you can make minor adjustments to your OAL during production without tools... "on the fly" as they say. Not perfect, but definitely easier.



Try it.

 

[GooseGestapo]

JimG (op).

It’s obvious that you have an accurate pistol and accurate bullets!
As to your “numbers”, two things not mentioned jump out at me...

1. Are you weighing every powder charge?
2. What primers are you using?

The 9mm cartridge is very sensitive to powder charge. The velocity variation you are seeing is possibly related to slight variations in powder charges which can be induced by slight variations in operation of an automatic powder dispenser.
Variations in primers are likewise notable in the small volume of the 9mm case. A different primer can make a significant difference in your statistics.

I’ve shot many thousands of 9’s through my S&W Performance Center PPC9’s. Pistols equal or better accuracy than the Sig210. I’ve shot National records and won matches in regionals and nationals. That is just say that I’ve found like others here have indicated here that with 9mm handguns at ranges to 50yds that sd and es mean little (but not nothing).
More importantly, bullet fit to barrel (compatibility), cartridge/bullet concentricity, and powder match to firing dynamics of the handgun. (ie: slide velocity, unlocking of barrel, ect), and bullet weight.

3n38 was developed for the 9mm for 147gr subsonic ammo for SMG’s. Yes it provides excellent velocity but for consistency with a 115gr bullet, there are better powders.
I actually won most matches with Sierra 115gr bullets and Win231/HP38 or Bullseye powder and Federal 100 primers. OFB brass, brand didn’t much matter, but mostly Federal or Starline. Velocities ran ~1,250fps from 6”bbl, and 1,225 from a 5”bbl.
(But mostly shoot 120gr home cast with LongShot because they’re accurate and cheap!)
If you want to see “small numbers”, try some Federal #100 Gold Medal Match primers and some Sport Pistol, VV N340 or N350 powders.
The BullsEye crowd (USAMU @Ft Benning uses Nosler 115gr JHP’s and N340 with slow twist barrels)
My S&W’s have 1/18.375” twist barrels. So, prefer 115’s, and 124-5’s.
Of more importance to Bullseye shooters at 50yds is that
1. The load is accurate,
2. Remains supersonic beyond 50yds because subsonic turbulence wrecks accuracy.
.22rf shooters are critically aware of this.
Yeah, you’re measuring a lot of “noise”.

 

[GooseGestapo]

OP,
Check with LongDayJake, a member here regarding his company’s 115gr JHP for shipping and costs to Canada.
I’ve switched to shooting his 115 instead of the Hornady HAP or XTP. It’s MORE accurate! And much cheaper.
Precision Delta of Ruleville, MS likewise makes a Hornady look-alike at MUCH better prices than the Hornady and is what the best shooters in NRA PPC are shooting.

 

[Jim Watson]

stopping power is proportional to energy which is proportional to velocity SQUARED.

Depends on whose definition of "stopping power" you use and how you interpret "stop."
The first organized attempt to compute "stopping power" was by Hatcher and it went, by a circuitous calculation, back to momentum.

Take the fat o-ring off a Lee lock ring (or any similar sized o-ring) and place it between the Dillon tool head and the seating die's lock ring.

That sounds like a good idea. I have Hornady Microjust seating dies in 9mm and .45, less expensive than Redding but functionally equivalent for my needs. But the next time I load bulk .38s or .44s, I will do it.

 

[JimGnitecki]

So a 22 Hornet has more stopping power, 729 ft/lbs, than a 45 Auto, 430ft/lbs?
I know which one I would use for defense, it isn’t a 22...
In using the .,22 Hornet as an "example" You've deliberately picked an outlier. But knowledgeable shooters, including the Texas Dept of public Safety (the Texas State police, where I worked for a couple of years) know from street experience that either a 1300 fps 9mm bullet or 357 SIG 125g at 1400 fps, will first penetrate a vehicle door and THEN still stop a perp, whereas a 45 acp 230 bullet at 850 fps will NOT.

I have not seen measuring to the fourth decimal for CBTO in pistols.
Don't get too excited about that. My digital caliper merely reads to 4 decimal places, but the 4th decimal digit is limited to "0" or "5", properly reflecting the precision and repeatability of the device's accuracy. I simply record everything it displays. When the variances you are looking to measure are measured in thousandths, you NEED that 4th digit.

I didn’t realize Berger made pistol bullets...
They don't, but they publish knowledgeable and experienced guiding content for shooters who want to understand and apply what Berger has learned while manufacturing bullets. They, and every other bullet manufacturer whose content I have found, all agree that energy content of a bullet, not power factor, and not caliber size, are what determine stopping power AND overall usability. Why do you suppose the most successful and practical hunting and sniper bullets have over time moved downward into the 6mm to .338" bore diameter?

How did you reach an ES of .0022 and .0017 when all your measurements end in zero or five?
Easy. You simply add up the 5 individual 5-shot ESs and divide by 5 to get the AVERAGE. Nothing mysterious.

All this math is fine, but math is a tool. No one wants to look at gasoline, they want to look at the Ferrari.

To that, how does it shoot now?
Be patient Grasshopper. I made these cartridges last evening. Shooting at an outdoor range in the rain and DARKNESS is not a good idea. It's still raining today, but I think I'll get to the range in the next couple of days, if the weather forecasters are correct.

See above in red font.

Jim G

 

[JimGnitecki]

The Dillon seating die is strange in that, unlike other dies, you need to move the whole die up/down to adjust cartridge OAL. Not simply the internal stem.

Here's a tip that might help in that area.... Take the fat o-ring off a Lee lock ring (or any similar sized o-ring) and place it between the Dillon tool head and the seating die's lock ring. Run the lock ring down to "snug" and leave it. This allows easy adjustment of the seating die body without disturbing anything else. The o-ring absorbs all the vibration, and the die setting won't ever change until the next twist of the die. In this way you can make minor adjustments to your OAL during production without tools... "on the fly" as they say. Not perfect, but definitely easier.

View attachment 987121

Try it.

This sounds good!! Thank-you!!

Jim G

 

[JimGnitecki]

JimG (op).

It’s obvious that you have an accurate pistol and accurate bullets!
As to your “numbers”, two things not mentioned jump out at me...

1. Are you weighing every powder charge?
2. What primers are you using?

The 9mm cartridge is very sensitive to powder charge. The velocity variation you are seeing is possibly related to slight variations in powder charges which can be induced by slight variations in operation of an automatic powder dispenser.
Variations in primers are likewise notable in the small volume of the 9mm case. A different primer can make a significant difference in your statistics.

I’ve shot many thousands of 9’s through my S&W Performance Center PPC9’s. Pistols equal or better accuracy than the Sig210. I’ve shot National records and won matches in regionals and nationals. That is just say that I’ve found like others here have indicated here that with 9mm handguns at ranges to 50yds that sd and es mean little (but not nothing).
More importantly, bullet fit to barrel (compatibility), cartridge/bullet concentricity, and powder match to firing dynamics of the handgun. (ie: slide velocity, unlocking of barrel, ect), and bullet weight.

3n38 was developed for the 9mm for 147gr subsonic ammo for SMG’s. Yes it provides excellent velocity but for consistency with a 115gr bullet, there are better powders.
I actually won most matches with Sierra 115gr bullets and Win231/HP38 or Bullseye powder and Federal 100 primers. OFB brass, brand didn’t much matter, but mostly Federal or Starline. Velocities ran ~1,250fps from 6”bbl, and 1,225 from a 5”bbl.
(But mostly shoot 120gr home cast with LongShot because they’re accurate and cheap!)
If you want to see “small numbers”, try some Federal #100 Gold Medal Match primers and some Sport Pistol, VV N340 or N350 powders.
The BullsEye crowd (USAMU @Ft Benning uses Nosler 115gr JHP’s and N340 with slow twist barrels)
My S&W’s have 1/18.375” twist barrels. So, prefer 115’s, and 124-5’s.
Of more importance to Bullseye shooters at 50yds is that
1. The load is accurate,
2. Remains supersonic beyond 50yds because subsonic turbulence wrecks accuracy.
.22rf shooters are critically aware of this.
Yeah, you’re measuring a lot of “noise”.

Goose Gestapo: THANK-YOU for taking the time to write down this very helpful information for me. You sound like you speak from long, analytical experience. I have copied your posting and pasted it into a document format in my Reloading folder, and will take the time to re-read and understand it as much as I am able to do so. I have no prior detailed guidance on exactly how to match a bullet to my pistol's throat dimensions and transition from throat to rifling (although one other shooter on this thread has tried but did not provide enough actual guidance on HOW to better see and measure what I have in my specific pistol). I'll try to find more info no that aspect.

I am currently using the Federal Gold medal Small Pistol primers (Part no. GM100M), but am down to just a few hundred left. Primers are now in short supply in Canada as well as in The U.S., so I had to grab a recent opportunity to buy 3000 of the Federal "regular" (not Gold Medal) small pistol primers, so will soon be forced to change over to them.

I am not weighing every charge, as I am trying to stay in "progressive loader" mode on my Dillon XL750. I do have a Pyrex powder hopper with its "new improved" baffle, so am getting better consistency than I was getting with the Dillon hopper and baffle, due to no more electrostatic "sticking" and the better baffle shape. My digital Lyman scale only reads to the nearest 0.1 grain, but I have been measuring the accuracy of the powder drop by making 5 to 10 consecutive drops and adding them cumulatively to the powder pan on the scale (removing the pan while actually pouring each drop into it). I am seeing perfect 8.0 grain additions as I add each drop to the pan, so I know that I am at most less than 0.5 grain over or under on each individual drop, but I don't know what else I can do without changing over to a single stage operation, which I am reluctant to do except for "special testing" scenarios.

I do have a tiny bit of ability to alter the pistol slide's dynamics, as I am using the DPMS recoil spring assembly versus the fragile OEM SIG recoil spring assembly. The DPMS assembly has THREE springs in it with specific assignments during the firing cycle. The system comes with 3 different versions of the external (changeable) spring and 2 different thicknesses of spacers. I have not yet experimented with those. DPMS intends the extra parts to be used to extend the life of the system to 50,000 rounds by periodic replacement of that 3rd external spring and the spacer, but obviously this also provides an experimental channel.

I'll study the powders you have mentioned. But, I want to ensure that I have at least 1300 fps velocity, as my personal standards require that any load I shoot informally for practice, or formally in competition, mimic what I would use in real life, and to me that means 1300 fps or more.

Thanks again very much for your posting and your style of presentation. It gives me a lot of digestable information to chew on.

Jim G

 

[fxvr5]

See above in red font.

Jim G

Be sure to measure all the groups you shoot, and let us know what they are. Thanks.

 

[JimGnitecki]

OP,
Check with LongDayJake, a member here regarding his company’s 115gr JHP for shipping and costs to Canada.
I’ve switched to shooting his 115 instead of the Hornady HAP or XTP. It’s MORE accurate! And much cheaper.
Precision Delta of Ruleville, MS likewise makes a Hornady look-alike at MUCH better prices than the Hornady and is what the best shooters in NRA PPC are shooting.

Thanks for the info! I have about 3000 of the HAP bullets now, as I recently had used up much of my initial 500 round test supply of them and a buddy found me an opportunity to buy a bulk pack of 3000 of them. Given the components shortage situation, I jumped on that opportunity. But when I run low again, I'll try LongDayJake's bullets!

Jim G

 

[JimGnitecki]

Be sure to measure all the groups you shoot, and let us know what they are. Thanks.

Sure! Just remember that I, not the pistol or the ammo, am currently the limiting factor. Hopefully, I'll have a decent day ext time I go out to the range so that we know I am measuring the ammo and not ME!

Jim G

 

[JimGnitecki]

sorry, duplicate post accidentally

Jim G

 

[JimGnitecki]

GooseGestapo: I found this article on matching throat lead-in angle to rifling:

https://riflebarrels.com/a-look-at-bullet-ogives-and-chamber-throat-angles/

Unfortunately, I don't know how to do the math that the author is trying valiantly to describe. Nor do I know the height of rifling lands in my pistol or how to describe the straight versus "secant curves formula" ogive of the HAP bullet. So I have no idea how well or how poorly the HAP 115g bullet mates with my throat angle . . . .

If this is in fact important (and the author is not even sure it is), how would I proceed?

Jim G

 

[GooseGestapo]

Don’t bother with the math.

Your barrel will like what it likes!
I’d try a box of 100 Noslers and a box of Sierras.
If it likes the Noslers, it’ll like the RMR match winners as they have a similar ogive. Likewise the Federal Classic BP9. My 5” PPC9 came with a 5-shot Ransom rest group that measures 0.478” at 25yds tested with the Federals. It likes the RMR’s. Maybe not so much now, as it has between 50-100,000rds through it.

If it likes the Hornadys, It’ll likely shoot well with Montana Gold or Precision Delta. They’re clones.
I’ve never seen a 9 not shoot as good as it’ll shoot with the Sierra JHP’s. But they’re $$$.

Unfortunately it’s as much trial and error as science.

Oddly enough, my standard 9 load until Remington components were discontinued in 2008 was the 115gr Remington JHP. My last order was for 2,000 which shipped cost me $88.00!
I shot the last 100 in the Alabama 2018 NRA “Dixie Nationals” tournament. I won the Stock Service SemiAuto Distinguished match and picked up my first distinguished points shooting my recently acquired box stock S&W M5906. It really liked the Remingtons...
The RMR match winners are my new standard.
p.s. the standard Feds are what I use... all my PPC revolvers are tuned to the Federals. They’re the hottest and most sensitive spp.

 

[kidneyboy]

Don’t bother with the math.

Your barrel will like what it likes!

Unfortunately it’s as much trial and error as science.

^^^^^^^^^^^^
Reloading in a nutshell.

 

[JimGnitecki]

Don’t bother with the math.

Your barrel will like what it likes!
I’d try a box of 100 Noslers and a box of Sierras.
If it likes the Noslers, it’ll like the RMR match winners as they have a similar ogive. Likewise the Federal Classic BP9. My 5” PPC9 came with a 5-shot Ransom rest group that measures 0.478” at 25yds tested with the Federals. It likes the RMR’s. Maybe not so much now, as it has between 50-100,000rds through it.

If it likes the Hornadys, It’ll likely shoot well with Montana Gold or Precision Delta. They’re clones.
I’ve never seen a 9 not shoot as good as it’ll shoot with the Sierra JHP’s. But they’re $$$.

Unfortunately it’s as much trial and error as science.

Oddly enough, my standard 9 load until Remington components were discontinued in 2008 was the 115gr Remington JHP. My last order was for 2,000 which shipped cost me $88.00!
I shot the last 100 in the Alabama 2018 NRA “Dixie Nationals” tournament. I won the Stock Service SemiAuto Distinguished match and picked up my first distinguished points shooting my recently acquired box stock S&W M5906. It really liked the Remingtons...
The RMR match winners are my new standard.
p.s. the standard Feds are what I use... all my PPC revolvers are tuned to the Federals. They’re the hottest and most sensitive spp.

Taking a quick look at the Vihtavouri 115g table loads, I see there will be an "elimination process" unless I change powders, or perhaps even if I do change powders. For example, the VV tables show the JHP Sierra not working with my 3N38 powder, and even with 3N37 the Sierra can apparently only be pushed to 1188 fps, which is way slower than my desired speed. And the Nosler is not shown at all.

I remember using Montana bullets years ago when I lived in Texas, and they worked fine for me, although I do not recall their consistency specs. But again, VV does not include them in its table, so I'd need to find a 115g HP in the table with similar dimensions and attributes, and start lower on the powder, or again, change powders.

I may do some or all of the above at some point, but first let's see if the current path already underway leads to a good outcome. I'm still early in that process, and the early results so far have been encouraging.

My gunsmith says he might have the bored out Redding seating insert ready for me tomorrow. That might be too late for my next range, as I will need to reconfigure the XL750, make a small batch of cartridges using that bored out insert, try 2 or 3 different COAL dimensions, and record the various cartridge dimensions, before going to the range again.

You likely did not see my postings on earlier threads on the forum where I explained at one point that my Texas Dept of Public Safety experience made me a believer in the 125g .357 SIG cartridge because of its stopping power and accuracy. I had a special SIG X5 Commemorative that SIG built only for TX DPS employees on an X5 chassis, and it was a fantastic firearm. 357 SIG is cost-practical in The U.S. because the brass is (normally) reasonably priced because that load is used by so many Federal LE agencies, but here in Canada it basically does not exist. A 115 g 9mm load at 1300+ fps is as close as I can get to that 357 SIG performance, with 425 to 450+ ft lb of energy on tap.

Jim G

 

[fxvr5]

Taking a quick look at the Vihtavouri 115g table loads, I see there will be an "elimination process" unless I change powders, or perhaps even if I do change powders. For example, the VV tables show the JHP Sierra not working with my 3N38 powder, and even with 3N37 the Sierra can apparently only be pushed to 1188 fps, which is way slower than my desired speed. And the Nosler is not shown at all.

The Sierra JHP bullet data is slow because it has a short nose and it has to be seated deep to fit in many chambers. This generally means it will reach max chamber pressure before it will produce speeds as fast as other bullets that don't have to be seated so deep.

Sierra has 3N38 load data for their 115 and 125 grain bullets. It would be a stretch to say that VV shows the JHP Sierra not working with 3N38. They just don't list it in their table. You don't want to over-interpret that to mean that it's a bad match.

 

[JimGnitecki]

The Sierra JHP bullet data is slow because it has a short nose and it has to be seated deep to fit in many chambers. This generally means it will reach max chamber pressure before it will produce speeds as fast as other bullets that don't have to be seated so deep.

Sierra has 3N38 load data for their 115 and 125 grain bullets. It would be a stretch to say that VV shows the JHP Sierra not working with 3N38. They just don't list it in their table. You don't want to over-interpret that to mean that it's a bad match.

Thanks for the alert about Sierra having 3N38 load data for some of their bullets. I'll take a closer look. The HAP 115g bullets in the first batch I bought average .5393" of which the shank portion is "about" .2750 - .2760" (can't measure the exact shank length easily without some form of jig). Only about .1486" to .1336" of the shank is inside the case, depending on how long a COAL I want.

If the Sierra JHP needs deeper seating, than yes, that's a problem with 3N38 because it will automatically be a compressed load AND a smaller combustion chamber, both leading to higher pressures.

VV says that all the loads in the table, including the one I am using that can be loaded to 8.7 grains maximum to get 1401 fps (I am loading only 8.0 g), meet SAAMI or the European pressure specs. That's impressive. It does illustrate how important the combination of bullet shape and slower burning powder can be in controlling peak pressure while getting very high velocity.

Brad MIller PhD.'s articles in Shooting Times over the past year or more show how he understands this, and manages to get really good accuracy too in at least some of the loads he has developed.

I feel fortunate that my SIG P210A will tolerate any COAL from about the VV minimum of 1.142" to the 1.1610" that still passes the plunk and rotate test. That gives me a COAL range to experiment within of at least .019", and possibly more if the combination of firearm, powder, and bullet will safely and productively tolerate the bullet going into the rifling a bit when chambered. I don't know how to safely and properly do that "into the rifling" experiment. I don't want to hurt the firearm or me.

Jim G

 

[fxvr5]

If the Sierra JHP needs deeper seating, than yes, that's a problem with 3N38 because it will automatically be a compressed load AND a smaller combustion chamber, both leading to higher pressures.

No, it's NOT a problem with 3N38. As with ANY POWDER, the charge is reduced as bullets are seated deeper to keep the pressure from exceeding the max. This is done for EVERY powder and EVERY bullet.

Look at VV's data with 3N37 and the 115 XTP versus the 115 Sierra JHP. They list 6.7 grains max for the XTP but only 5.7 grains max with the Sierra JHP. See how that works? They could just reduce the load with 3N38 until it stays within the pressure limit.

An example is given at this link: https://www.shootingtimes.com/editorial/fast-9mm-loads/388612 where the charge with 3N37 is reduced from a long OAL (1.142") with the 115 XTP when seated to a shorter length (1.080" OAL) to keep the pressure the same.

I feel fortunate that my SIG P210A will tolerate any COAL from about the VV minimum of 1.142" to the 1.1610" that still passes the plunk and rotate test.

Yes, you're lucky the P210 allows this. Many of my S&W M&P barrels require the 115 HAP bullet to be seated much shorter - no longer than 1.100".

 

[CMV]

I'm glad it doesn't need to be this complex However you want to approach it, as long as it's safe, have fun with it. My experience for both .223 and .308 was I was frustrated because my SD was way higher than what most people report- and for something so common, using popular components, not getting the same had me real worried my process was all jacked up. But both loads hit 2" targets at 300 yds consistently (off a bench, rest or multiple bags, 12x scope) so I quit beating myself up about it, quit over-processing prep work, and haven't even calculated an SD since. I'm pleased with the performance, my range only goes to 300 yds, and I place 0 value on what an excel spreadsheet would tell me vs what the round ringing steel tells me.

I like threads like this that illustrate how we all have different goals, different approaches. i.e. for 9mm my metrics are cost per round and how fast can I fill a 50cal can. Sure, my loads perform as well or better than say WWB or UMC or Blazer Brass (not exactly the gold standard ), but I'm stuffing 115gr ACME coated cast into mixed HS brass with a moderate W231/H38 charge ignited with wolf or Fiocchi primers. I'd have to look in notebook, but right around a dime, 500 per hour. I couldn't care less about SD, COAL variation, could they group .5" tighter, etc. Will they hit any steel 4" or larger at 10-15 yds? do they function reliably in any of the 25ish 9mm I have? Are they cheap enough to burn 1k/month and not worry about it? Can I load quickly enough and without so much fuss it feels like a chore? Those things are what's important to me.

I do load some stuff for precision where other things matter and I don't care about cost or speed, but that's maybe 5% of the time.

And something I kind of stumbled into and was an 'aha moment' was my 223 loads. Taking great care doing my target loads for a built Rem 700 or 24" varmint AR results in .5" to .75" groups at 100 yds (bench, rest, at least 12x magnification, calm day, i'm having a good day, etc). But, sub in my mass produced general range ammo and using Hornady 2266 instead of fmj, I'm still an inch or better. And maybe not reliably hitting the 2" target at 300 yds (about 1/2 will), but still fist sized groups at very worst. Trimmed with an RT1500, loaded with mix of Lee and Dillon dies, powder dropped with Dillon powder measure, brisk pace on 650 for both prep and loading. Vs all the work on the target loads, trickling, sorting, weighing, measuring, single stage batch process, etc. Once I saw that, I was done stressing about every little detail. Get the components right, get the load right, have real good notes that result in repeatable setups, and buy everything in ginormous bulk qty at once to eliminate lot-to-lot variation. Maybe I just got lucky, maybe I'm FOS, maybe my needs/expectations are much different than a competitive shooter or someone wanting to headshot prairie dogs 600 yds away? Dunno, but after seeing how much time and effort and $ it took to get the best loads I could make for those guns and then seeing simpler/faster/cheaper methods still yielding [not as good but still] very good results, it's hard to justify getting caught up in the minutiae (how we each define what exactly constitutes minutiae is probably a whole different topic!).

Anyway, chase every little detail. Chase every aspect you can measure. Do maths on top of maths. Plot, graph, trend. Aggregate data. Cherry pick data. Shoot out the star with one magazine and win the teddy bear If that brings you joy and it feels like recreation, carry on. If it is a source of stress, step back, simplify, and say 'good enough' as appropriate.

I will throw this out there just to be jerk and introduce variables I've spent a lot of time as a supervisor and manager over machinists. I'm a hobby machinist but not good enough I'd dare say I'm a real machinist. But working in professional environments where 2 thou may as well be a quarter mile because no tolerance was that generous. One thing I quickly learned is people cannot measure as precisely as they think they can. Put the same set of calibrated measuring tools in 10 different skilled, veteran machinists (or QA inspectors) hands, don't let them know what the part 'should be', and see the variation in readings. I have no idea your skill level or the quality/selection of measuring tools you use, but I'd bet a coke right now that a CMM would show at least a 3 thou spread in your manual measurements from what they really are. Don't believe me? grab the little 1" test block that came with your calipers or micrometer. Measure it 10 times and see how many times you're squeezing a bit more or backing off and closing again because it read .999 or 1.01 or worse.

 

[JimGnitecki]

CMV, I get your point. But as you speculated, I do enjoy the processes involved. If I didn't, I'd relax the specs!

Jim G