Not all 9mm jacketed/plated bullets are sized the same

[LiveLife]

In addition to the comparison plated bullet testing thread, I am testing/preparing for the inevitable comparison jacketed bullet testing thread - https://www.thehighroad.org/index.p...ng-at-25-50-yards.808446/page-2#post-10346110

While posting on another thread regarding different sizing of 9mm bullets, I thought it would benefit members with different groove diameter barrels as many factory barrels are oversized at .356"+. Since bullet-to-barrel fit is a significant reloading variable, using larger sized bullets for oversized barrels should improve accuracy.

I measured some bullets ordered late 2016 and here are the results:

Hornady 115 gr HAP - 0.355" (Box indicated 0.355")
Hornady 125 gr HAP - 0.356" (Box indicated 0.356")
Precision Delta 124 gr JHP - 0.355" (Advertised at 0.355")
RMR 115 gr FMJ/124 gr JHP - 0.3555" (Advertised at 0.355")
Winchester 115 gr FMJ - 0.355" (Advertised at 0.355")
Zero 115 gr FMJ - 0.356" (Advertised at 0.355")

Berry's 115/124 gr RN regular/thick plated - 0.356" (Box indicated 0.356")
Hunting Shack Munitions 115/124 gr RN - 0.356" (Box indicated 0.355")
Rainier 115/124 gr RN - 0.355" (Box indicated 0.355")
RMR 115 gr Hardcore Match RN thick plated - 0.3565" (Advertised at 0.356")
RMR 124 gr Hardcore Match RN thick plated - 0.3565" (Advertised at 0.3565")
Speer 124 gr Gold Dot HP - 0.3555" (Advertised at 0.355")
Speer 115/124 gr TMJ - 0.3555" (Box indicated 0.355")
X-Treme 115/124 gr RN regular/thick plated - 0.355" (Advertised at 0.355")

 

[vaalpens]

bds, Thanks for starting another interesting thread that will obviously add some additional data points for the reloader.

I ran into some trouble when I posted bullet diameters I measured. Can you please indicate what instrument you use and where you take your reading when measuring the bullet diameter. I am trying to be more consistent when taking these measurements, so any how-to/advice will be appreciated.

 

[Walkalong]

Unless I am mistaken, Zero makes 9MM .355 and .38 Super .356. I always bought the .356 and shot them in both calibers.

And no more nearest .0005, even with good calipers, use a micrometer to get diameters.

Practice trying to measure to the nearest .0001.

 

[JimKirk]

I ran into a similar measuring error that I had done... Vaalpens had asked me a question about the Hornady 124 gr HAP bullet ... I had measured(with calipers) them way before he had ask and I rattled off .355" . ..But I had the micrometer out one day and sure enough they are .356" . ..

 

[LiveLife]

Can you please indicate what instrument you use and where you take your reading when measuring the bullet diameter.

Wait a minute - I am not a machinist (although I have a hobby/appreciation of collecting Starrett and other American made machinist/vintage tools).

I am using both Harbor Freight digital and brand new Frankford Arsenal dial calipers. Bullets were measured several different places on the same bullet base to ensure roundness. Yes, there were few out-of-round bullets which were discarded. The bullet bases were measured with the thick portion of the calipers and they consistently read .355" or .356" depending on sizing as shown on video below.



I retired the dial calipers I bought from MidwayUSA about 25 years ago when I started reloading after getting the Harbor Freight digital calipers several years ago. The HF digital calipers I have definitely read consistent to bullet sizing without play which the old dial calipers did not. The new Frankford Arsenal dial calipers read like HF digital calipers, precise without play.

The .355" sized bullets definitely consistently read .355" on the line while the .356" sized bullet definitely consistently read .356" on the line. There is no mistaking between two sizes.

As to .3555"/.3565" sized bullets, they consistently read between lines mid point. Jake from RMR even verified by PM that 124 gr Hardcore Match RN bullets are sized at .3565" and 115 gr Hardcore Match RN are targeted for .356" and allowed .0005" sizing variance.

Speer 115/124 gr TMJ bullets read between .3555" and close to .356" with most of them reading at .3555".

For me, this is good enough to separate .355" sized bullets from .356" sized bullets to do bullet selection based on groove diameter of the barrel.

I am open to sending bullet samples to those with more precise measuring instruments for verification.

 

[vaalpens]

The case I was referring to were my measurements of the new RMR 124gr JHP's. This is how Jake from RMR described how the bullets are made/measured:

We make this bullet a little different than others do. There is some variance in the diameter from the top of the body to the bottom. Typically, starting about halfway up the body is where our final nose finish station hits. Typically the upper half of the bullet comes out to .3555 and the base of the bullet was coming out at .3554. We were using digital Mitutoyo micrometers to test the diameters. I'm kind of curious why the .3545 was there. Do you know where on the bullet you measured it from?

I then standardized how I measured the bullets and saw a consistent .3555" diameter. This is the post where I corrected my measuring error:
https://www.thehighroad.org/index.p...house-bullet-evaluation.818511/#post-10498503

 

[LiveLife]

Yes, I could see how you could get slightly different readings using the tips of the calipers if a lot of force was applied.

And keep in mind that bullets can be out-of-round (imagine the impact force of a medium flat rate freight box of bullets slamming on the concrete floor ) and I discard them from my measurements once I detect them.

As shown in the video, I simply slide the caliper jaws until they contact the bullet base and stop. I check several different spots on the same bullet base to ensure roundness of the bullet. The readings are usually consistent to .355" or .356" on the line.

 

[Walkalong]

And some bullets will have a pressure ring at the base which will measure more than the rest of the full diameter shank.

 

[Walkalong]

I could see how you could get slightly different readings using the tips of the calipers if a lot of force was applied.

That is the trick in consistent and proper measurements with calipers or micrometers, especially when trying for the nearest .0001, and especially the right one.

Standards are good for practicing "feel" as well as checking tools accuracy.

 

[DeadEye9]

In addition to the comparison plated bullet testing thread, I am testing/preparing for the inevitable comparison jacketed bullet testing thread - https://www.thehighroad.org/index.p...ng-at-25-50-yards.808446/page-2#post-10346110

While posting on another thread regarding different sizing of 9mm bullets, I thought it would benefit members with different groove diameter barrels as many factory barrels are oversized at .356"+. Since bullet-to-barrel fit is a significant reloading variable, using larger sized bullets for oversized barrels should improve accuracy.

I measured some bullets ordered late 2016 and here are the results:

Hornady 115 gr HAP - 0.355" (Box indicated 0.355")
Hornady 125 gr HAP - 0.356" (Box indicated 0.356")
Precision Delta 124 gr JHP - 0.355" (Advertised at 0.355")
RMR 115 gr FMJ/124 gr JHP - 0.3555" (Advertised at 0.355")
Winchester 115 gr FMJ - 0.355" (Advertised at 0.355")
Zero 115 gr FMJ - 0.356" (Advertised at 0.355")

Berry's 115/124 gr RN regular/thick plated - 0.356" (Box indicated 0.356")
Hunting Shack Munitions 115/124 gr RN - 0.356" (Box indicated 0.355")
Rainier 115/124 gr RN - 0.355" (Box indicated 0.355")
RMR 115 gr Hardcore Match RN thick plated - 0.3565" (Advertised at 0.356")
RMR 124 gr Hardcore Match RN thick plated - 0.3565" (Advertised at 0.3565")
Speer 124 gr Gold Dot HP - 0.3555" (Advertised at 0.355")
Speer 115/124 TMJ - 0.3555" (Box indicated 0.355")
X-Treme 115/124 regular/thick plated - 0.355" (Advertised at 0.355")

This is all great information to have, however I have found that this measurement of bullet diameter is more a variable than a particular size. By that I mean different lots of the same bullet will have different measurements. This kind of defeats the purpose of having a standard "list" which is why I've never personally done this myself. What I do is measure the particular bullets I'm going to load for the specific firearm I'm going to use them in, should I be looking for match grade accuracy. For just Action Pistol and IDPA type stuff, plain Jane XTPs have been plenty accurate for years. Also I want to point out that bullet size has a big impact on pressure bleed off as well with regards to the size of the Bore. A tighter fitting bullet will contain more pressure, get more velocity and more accuracy, whereas a loose fitting bullet will bleed some pressure to the environment around the bullet therefore creating less chamber pressure, less velocity and partially degrading accuracy. You also get more friction/wear on your barrel if the projectiles are too loose, as the bullet can sort of "flap around" instead of spinning in solely a circular motion with the rifling. All that being said, just about any commercial bullet in the correct caliber as far as handguns go will be just as inherently accurate as the shooter could possibly be anyway. If your really looking for absoluTe fitment, slug your Bore then cast your own bullets to the exact size needed. Other than that it's hard to get exactly the same diameter bullet every time when you buy thousands at a time. It's also a futile effort in a lot of ways because for 95% of shooters out there any off the shelf pistol bullet will be fine for their shooting needs. Thanks for taking the time to post all this info though, I'm sure a lot of people are thinking about this all the time when accuracy is down for their pet loads/pistols.

 

[AR-Bossman]

That is the trick in consistent and proper measurements with calipers or micrometers, especially when trying for the nearest .0001, and especially the right one.

Standards are good for practicing "feel" as well as checking tools accuracy.

I only recently went and grabbed a standard (2") out of another set of mics to check my calipers. All my digital ones were off and a couple of my dial ones were off. Since I was just grabbing the nearest set when I was setting of some measurements like case length.. I ended up missing my number because nothing I was using was accurate.

I now standard check and set my caliper before I use it.

 

[LiveLife]

I think we are starting to drift away from the intent of the OP.

The intent was that 9mm bullets come in different sizing just as 9mm barrels come with different groove diameters. So if your .356"+ groove diameter barrel has accuracy issues with .355" sized bullets, using larger sized .3555"-.3565" diameter bullets may help improve accuracy.

Fact is, not all 9mm bullets come sized .355" but .3555", .356" and even .3565".

As to how accurately we can measure bullet diameter is for another thread discussion.

 

[Tilos]

I buy bullets @ 0.358 and push them thru whatever sizing die that gets me the diameter I want to load...same coated/no lube groove bullet for 38/357/9mm.
Even if I want to load 0.358 bullets, I push them thru a 0.358 sizer for a rounder/uniform bullet.
So what they measure as received (I don't cast) really doesn't matter much to me.
jmo

 

[Louca]

That is the trick in consistent and proper measurements with calipers or micrometers, especially when trying for the nearest .0001, and especially the right one.

Don't mean to get too picky with things, but if a bullet is measured with a micrometer or other device that is precise to a tenth of a thousandth of an inch, the measurement should show 4 digits to the right of the decimal point, even if the rightmost digit is a zero. A number stated as .356 essentially states that the measurement is only precise to a thousandth of an inch, and the tenths of thousandths are unknown.

 

[Sunray]

Plated and jacketed bullets are not in any way the same thing. Plating is not a jacket. Nor is all plating the same thickness. Berry's, for example, run between 3.5 and 8 thou. Campro's run 6 to 8 thou.
"....3555"..." That last 5 is 5/10,000. .0001" is 1/10,000. Absolutely no reason, advantage or difference to measure that small. However, SAAMI spec for 9mm bullet diameter is .3555" -.003". So they can be .3525" and still be within spec.

 

[vaalpens]

bds, my apologies if I sidetracked the thread with my "how to measure" post, but following are some 9mm diameters using my new measuring methodology. Obviously it will be nice if somebody can confirm:

New RMR 124 gr JHP - 0.3555" (Advertised at 0.355")
Sierra V-Crown 125gr JHP #9925 - 0.3545" (Box indicates 0.355")

 

[Walkalong]

As to how accurately we can measure bullet diameter is for another thread discussion.

I disagree, and think the point was relevant. Measurements need to be accurate. But aside from that, I will drop it.

 

[LiveLife]

OK Walkalong, you talked me into it.

In the spirit of "Myth busting digital scales" thread where stainless steel Ohaus check weights were ordered to verify the accuracy of digital scales, I ordered pin gauges in .355", .400" and .451" to verify the accuracy of my calipers.

I will update the thread once the gauges arrive.

 

[Buck13]

Standards are good for practicing "feel" as well as checking tools accuracy.

If the standard is made of steel, and the test object is lead skinned with a bit of copper, will that affect the "feel?"

Not that it matters to me, since if there was a published volume titled "Handloading for the Complete Klutz," I would be the target market, but I'm curious about the pitfalls of measuring soft metals.

 

[Walkalong]

https://www.amazon.com/Mitutoyo-167...489263050&sr=1-9&keywords=measuring+standards

Heat Insulating handle to prevent expansion due to body temperature

Designed to be most accurate @ 68 degrees. How accurate do you want to be, but yes, a soft metal would accept less force and still be accurate, but a learned and repeated "force" with which we close the micrometer on an object is what repeat-ability and precision is all about.

That said, if we are off .0001 or .0002 with a quality micrometer, it will be better than a less precise dial caliper (Compared to a micrometer) rounding off to the nearest .0005. And we can have more faith in the numbers.

 

[LiveLife]

OK Walkalong, you talked me into it.

In the spirit of "Myth busting digital scales" thread where stainless steel Ohaus check weights were ordered to verify the accuracy of digital scales, I ordered pin gauges in .355", .400" and .451" to verify the accuracy of my calipers.

I will update the thread once the gauges arrive.

OK, .451" pin gauge arrived from Zoro (.355" and .400" pin gauges will ship when they are available).

With my eyes closed, I closed the Frankford Arsenal dial calipers on the thicker part of the calipers then read the reading - .451" right on the line. I then closed the calipers on the tip of the calipers - again, .451" on the line.

So is this good enough or do I need to get a micrometer?

Here are my bullet measurements again:

Hornady 115 gr HAP - 0.355" (Box indicated 0.355")
Hornady 125 gr HAP - 0.356" (Box indicated 0.356")
Precision Delta 124 gr JHP - 0.355" (Advertised at 0.355")
RMR 115 gr FMJ/124 gr JHP - 0.3555" (Advertised at 0.355")
Winchester 115 gr FMJ - 0.355" (Advertised at 0.355")
Zero 115 gr FMJ - 0.356" (Advertised at 0.355")

Berry's 115/124 gr RN regular/thick plated - 0.356" (Box indicated 0.356")
Hunting Shack Munitions 115/124 gr RN - 0.356" (Box indicated 0.355")
Rainier 115/124 gr RN - 0.355" (Box indicated 0.355")
RMR 115 gr Hardcore Match RN thick plated - 0.3565" (Advertised at 0.356")
RMR 124 gr Hardcore Match RN thick plated - 0.3565" (Advertised at 0.3565")
Speer 124 gr Gold Dot HP - 0.3555" (Advertised at 0.355")
Speer 115/124 gr TMJ - 0.3555" (Box indicated 0.355")
X-Treme 115/124 gr RN regular/thick plated - 0.355" (Advertised at 0.355")

 

[Walkalong]

Just out of curiosity, did you get a plus or minus pin gauge? (.451 plus .0002 or minus .0002)

 

[LiveLife]

I got the minus gauge (they did not have the plus gauge in stock) - https://www.zoro.com/vermont-gage-pin-gage-minus-0451-in-black-911245100/i/G3510577/

It's Vermont Gage .451 - Class ZZ Pin Gage Black Guard
Part Number 911245100

 

[LiveLife]

If the standard is made of steel, and the test object is lead skinned with a bit of copper, will that affect the "feel?"

I tested the bullets and pin gauge with eyes open/closed and for my hands, they felt same.

I pushed on the thumb wheel with light to medium pressure until I couldn't push anymore.

 

[Jesse Heywood]

So is this good enough or do I need to get a micrometer?

Only if you are using a mike to measure the barrel internals. Beyond the third digit becomes insignificant. But if you need a full analysis on the statistics, I took the graduate level class about 1987, and have forgotten more than I learned. So you will need someone else to answer the question.