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THE CARTRIDGE LIBRARY · PISTOL

9mm Luger

Also called 9×19mm or 9mm Parabellum, this is a rimless semiautomatic-pistol cartridge with extensive factory weight and construction options. Luger is the cartridge name; it does not limit the ammunition to Luger-brand pistols.

2A Ledger reference desk · Sources checked October 18, 2026

9mm Luger · Studio brass dimensional referenceDimensions in inches and millimeters. Overall length minimum: 1.000 in, 25.400 mm; Overall length maximum: 1.169 in, 29.693 mm; Case length maximum: 0.754 in, 19.152 mm; Rim diameter maximum: 0.394 in, 10.008 mm; Bullet maximum: 0.3555 in, 9.030 mmOVERALL · MIN–MAX1.000–1.169 in25.400–29.693 mmCASE LENGTH · MAX0.754 in19.152 mmBULLET Ø · MAX0.3555 in9.030 mmRIM Ø · MAX0.394 in10.008 mm
Published cartridge dimensions · SAAMI drawing ↗
Read the dimensions
Overall · min–max
1.000–1.169 in
25.400–29.693 mm
Case length · max
0.754 in
19.152 mm
Bullet maximum
0.3555 in
9.030 mm
Rim diameter · max
0.394 in
10.008 mm

Know the exact name

At a glance

Cartridge family
Pistol
Bullet specification
0.3555 in / 9.030 mmBullet maximum
Factory examples
51 loadsSelected, sourced examples below
Weight in cited examples
70–158 grGrains measure mass, not powder charge

9mm Luger is identified by its complete cartridge designation. The resource-table alternative is 9 × 19 mm · 9 mm Parabellum. A caliber number, bullet diameter, or family resemblance on its own does not identify ammunition compatibility.

9mm Luger, .380 Auto, 9mm Makarov, and 9×21mm are different cartridges. +P is a separate pressure category; +P+ is not a SAAMI-standard pressure category.

Dimensions: open the exact dimensional drawing ↗. The displayed number is bullet maximum, rather than an assertion that every manufactured projectile or barrel has this exact diameter.

Origins & evolution

Background & development

The 9 mm Luger was introduced in 1902 for the Luger automatic-pistol system. German naval adoption followed in 1904, and the army adopted it in 1908. Those early service decisions helped establish a cartridge whose later reach extended far beyond the original pistol.

Its American commercial rise came much later. Smith & Wesson began developing 9 mm pistols for police and military markets in the 1950s, while broader U.S. enthusiasm accelerated in the late 1970s and 1980s as more high-capacity service pistols became available. Military and police procurement then reinforced an already international ammunition market. The familiar names 9 mm Luger, 9×19 mm and 9 mm Parabellum preserve parts of that original commercial and service identity. They should not be shortened to a generic “9 mm” when distinguishing it from the several other cartridges that use that nominal caliber.

Historical sources: Sierra: 9mm Luger cartridge history ↗

Construction changes the story

Loads, variations & specialty offerings

Practice & target

Full-metal-jacket, plated, lead, and wadcutter bullets describe different constructions. Grain weight is projectile mass; it does not state a powder charge or guarantee recoil.

Expanding factory bullets

JHP, XTP, FTX, HST, and similar product names refer to particular designs. Muzzle energy alone does not show expansion, penetration, or reliability in a particular firearm.

Specialty load families

Reduced-recoil, subsonic, monolithic, and heavier-bullet offerings are product-specific. A +P marking is a pressure category where standardized, not simply a heavier bullet. Follow the maker’s exact product and firearm guidance.

The expanded factory selection spans 70–158 grains. Exact products and source conditions appear in the table.

Bullet construction background: Hornady: anatomy of a bullet ↗. Exact product descriptions and velocities are cited in the factory table.

Factory-labeled subsonic additions include Aguila, Blazer, Magtech, Remington, Sellier & Bellot, Winchester. The table also distinguishes ordinary factory loads. Published test conditions and product-specific notes accompany each addition; no velocity curve is inferred from one muzzle specification.

From the factory catalog

Compare all 51 cited factory load records
Factory catalog examples, not purchase recommendations. V / -V denotes a vented test barrel where shown by the source. Unstated test lengths have not been inferred.
Maker / productBullet massPublished constructionMuzzle velocityTest barrelSource
FederalAE9LF170 gr
4.54 g
RHT1,625 fps
495 m/s
4 inFederal · PDF p. 61 ↗
Hornady90240100 gr
6.48 g
FTX®1,125 fps
343 m/s
4 inHornady · PDF p. 191 ↗
FederalAE9DP115 gr
7.45 g
FMJ1,180 fps
360 m/s
4 inFederal · PDF p. 61 ↗
FederalPD9P2115 gr
7.45 g
JHP1,180 fps
360 m/s
4 inFederal · PDF p. 60 ↗
FederalTP9VHP1115 gr
7.45 g
JHP1,180 fps
360 m/s
4 inFederal · PDF p. 61 ↗
FederalWM5199115 gr
7.45 g
FMJ1,125 fps
343 m/s
4 inFederal · PDF p. 61 ↗
Hornady90244115 gr
7.45 g
XTP®1,155 fps
352 m/s
4 inHornady · PDF p. 191 ↗
Hornady90250115 gr
7.45 g
FTX®1,135 fps
346 m/s
4 inHornady · PDF p. 191 ↗
Hornady90281115 gr
7.45 g
MonoFlex® +P1,100 fps
335 m/s
4 inHornady · PDF p. 191 ↗
FederalAE9AP124 gr
8.04 g
FMJ1,150 fps
351 m/s
4 inFederal · PDF p. 61 ↗
FederalAE9N1124 gr
8.04 g
TMJ1,120 fps
341 m/s
4 inFederal · PDF p. 61 ↗
FederalAE9SJ2124 gr
8.04 g
TSJ1,050 fps
320 m/s
4 inFederal · PDF p. 61 ↗
FederalAE9SJ4124 gr
8.04 g
TSJ1,150 fps
351 m/s
4 inFederal · PDF p. 61 ↗
FederalC9124A124 gr
8.04 g
FMJ1,090 fps
332 m/s
4 inFederal · PDF p. 61 ↗
FederalC9N882124 gr
8.04 g
FMJ1,260 fps
384 m/s
4 inFederal · PDF p. 61 ↗
FederalP9HS1124 gr
8.04 g
HYDRA-SHOK1,120 fps
341 m/s
4 inFederal · PDF p. 60 ↗
FederalP9HST1S124 gr
8.04 g
HST1,150 fps
351 m/s
4 inFederal · PDF p. 60 ↗
FederalP9HST1TM100124 gr
8.04 g
HST1,150 fps
351 m/s
4 inFederal · PDF p. 60 ↗
FederalP9HST3S124 gr
8.04 g
HST +P1,200 fps
366 m/s
4 inFederal · PDF p. 60 ↗
FederalPD9P1124 gr
8.04 g
JHP1,150 fps
351 m/s
4 inFederal · PDF p. 60 ↗
Hornady90216124 gr
8.04 g
FlexLock® +P1,175 fps
358 m/s
4 inHornady · PDF p. 191 ↗
Hornady90224124 gr
8.04 g
XTP® +P1,175 fps
358 m/s
4 inHornady · PDF p. 191 ↗
Hornady90242124 gr
8.04 g
XTP®1,110 fps
338 m/s
4 inHornady · PDF p. 191 ↗
FederalAE9SJPC1130 gr
8.42 g
TSJ1,130 fps
344 m/s
16 inFederal · PDF p. 61 ↗
FederalP9HSD1135 gr
8.75 g
HYDRA-SHOK DEEP1,060 fps
323 m/s
4 inFederal · PDF p. 60 ↗
Hornady90226135 gr
8.75 g
FlexLock® +P1,110 fps
338 m/s
4 inHornady · PDF p. 191 ↗
Hornady90236135 gr
8.75 g
FlexLock®1,010 fps
308 m/s
4 inHornady · PDF p. 191 ↗
FederalS9SJT2138 gr
8.94 g
SHP1,050 fps
320 m/s
4 inFederal · PDF p. 61 ↗
Hornady90268138 gr
8.94 g
DGH +P1,150 fps
351 m/s
4 inHornady · PDF p. 191 ↗
FederalAE9FP147 gr
9.53 g
FMJ FP1,000 fps
305 m/s
4 inFederal · PDF p. 61 ↗
FederalAE9N2147 gr
9.53 g
TMJ1,000 fps
305 m/s
4 inFederal · PDF p. 61 ↗
FederalAE9SJ3147 gr
9.53 g
TSJ1,000 fps
305 m/s
4 inFederal · PDF p. 61 ↗
FederalGM9AP1147 gr
9.53 g
FMJ MATCH900 fps
274 m/s
4 inFederal · PDF p. 60 ↗
FederalP9HST2TM100147 gr
9.53 g
HST1,000 fps
305 m/s
4 inFederal · PDF p. 60 ↗
FederalP9SHC1147 gr
9.53 g
SOLID CORE +P1,120 fps
341 m/s
4 inFederal · PDF p. 60 ↗
Hornady90282147 gr
9.53 g
XTP®975 fps
297 m/s
4 inHornady · PDF p. 191 ↗
Hornady90287147 gr
9.53 g
XTP®975 fps
297 m/s
4 inHornady · PDF p. 191 ↗
FederalAE9SJAP1150 gr
9.72 g
TSJ890 fps
271 m/s
4 inFederal · PDF p. 61 ↗
Fiocchi9APBHP124 gr
8.04 g
JHPStandard factory load. Its published velocity is not a guarantee of subsonic performance in every firearm or temperature.1,100 fps
335.3 m/s
Not statedFiocchi · PDF p. 28 ↗
Fiocchi9APDHP147 gr
9.53 g
JHPStandard factory load. Its published velocity is not a guarantee of subsonic performance in every firearm or temperature.975 fps
297.2 m/s
Not statedFiocchi · PDF p. 28 ↗
Fiocchi9APD147 gr
9.53 g
FMJStandard factory load. Its published velocity is not a guarantee of subsonic performance in every firearm or temperature.975 fps
297.2 m/s
Not statedFiocchi · PDF p. 31 ↗
Fiocchi9APE158 gr
10.24 g
FMJStandard factory load. Its published velocity is not a guarantee of subsonic performance in every firearm or temperature.850 fps
259.1 m/s
Not statedFiocchi · PDF p. 31 ↗
WinchesterSUP9147 gr
9.53 g
Super Suppressed · FMJWinchester February 4, 2026 product table. Different package variants are retained where published specifications differ; SUP300BLK and SUP300BLK2 share one ballistic record.990 fps
301.8 m/s
Not statedWinchester · source ↗
Blazer5203S147 gr
9.53 g
Brass Clean-Fire Suppressor · TMJThe catalog also prints a muzzle-energy value inconsistent with its 147-grain/900-fps row. Energy in this library is calculated from the published mass and velocity; the inconsistent energy cell is not copied.900 fps
274.3 m/s
4 inBlazer · PDF p. 30 ↗
Magtech9G147 gr
9.53 g
Subsonic · FMJ flat990 fps
301.8 m/s
4 inMagtech · PDF p. 20 ↗
Magtech9K147 gr
9.53 g
Subsonic · JHP990 fps
301.8 m/s
4 inMagtech · PDF p. 20 ↗
Magtech9PMG147 gr
9.53 g
Polymatch · LPC892 fps
271.9 m/s
4 inMagtech · PDF p. 20 ↗
Aguila1E097719147 gr
9.53 g
Subsonic · FMJ flat point950 fps
289.6 m/s
Not statedAguila · PDF p. 20 ↗
Remington28435147 gr
9.53 g
Subsonic · flat nose enclosed base950 fps
289.6 m/s
4 inRemington · PDF p. 39 ↗
Sellier & BellotV310552 / SB9SUBA140 gr
9.07 g
Subsonic · FMJOriginal product table uses meters and m/s; test barrel 150 mm. Chart coordinates are exact unit conversions, not interpolated source points.1,000.7 fps
305 m/s
5.9055 inSellier & Bellot · source ↗
Sellier & BellotV311662 / SB9SUBB150 gr
9.72 g
Subsonic · FMJOriginal product table uses meters and m/s; test barrel 150 mm. Chart coordinates are exact unit conversions, not interpolated source points.1,000.7 fps
305 m/s
5.9055 inSellier & Bellot · source ↗

Explore the published data

Ballistics you can inspect

Select a legend entry to add or remove its line. Hover or tap a plotted point, or use the position slider. With the graph focused, arrow keys move the inspector. Solid dots identify source points; dashed connectors show estimates between them. Load construction, pressure category, and test setup can differ even at the same grain weight.

Read the original values as accessible tables

9mm Luger: velocity by barrel length

Barrel length (in): velocity (fps). Source points and stated unit conversions; intermediate estimates are excluded.
Exact loadSource / publisherPublished points
Cor Bon 90 gr. JHP +PBBTI2: 1,215; 3: 1,345; 4: 1,444; 5: 1,539; 6: 1,566; 7: 1,619; 8: 1,634; 9: 1,663; 10: 1,647; 11: 1,690; 12: 1,716; 13: 1,738; 14: 1,767; 15: 1,768; 16: 1,740; 17: 1,766; 18: 1,754
Cor Bon 115 gr. JHP +PBBTI2: 1,134; 3: 1,245; 4: 1,316; 5: 1,372; 6: 1,402; 7: 1,446; 8: 1,458; 9: 1,476; 10: 1,474; 11: 1,496; 12: 1,514; 13: 1,517; 14: 1,532; 15: 1,536; 16: 1,525; 17: 1,550; 18: 1,543
Cor Bon 125 gr. JHP +PBBTI2: 1,061; 3: 1,170; 4: 1,226; 5: 1,282; 6: 1,312; 7: 1,329; 8: 1,366; 9: 1,369; 10: 1,372; 11: 1,372; 12: 1,385; 13: 1,477; 14: 1,405; 15: 1,392; 16: 1,430; 17: 1,421; 18: 1,449
Cor Bon 115 gr. DPXBBTI2: 1,132; 3: 1,215; 4: 1,265; 5: 1,315; 6: 1,332; 7: 1,350; 8: 1,366; 9: 1,377; 10: 1,379; 11: 1,391; 12: 1,380; 13: 1,427; 14: 1,440; 15: 1,416; 16: 1,476; 17: 1,455; 18: 1,458
Federal 115 gr. JHPBBTI2: 948; 3: 1,029; 4: 1,094; 5: 1,166; 6: 1,188; 7: 1,223; 8: 1,234; 9: 1,238; 10: 1,253; 11: 1,268; 12: 1,282; 13: 1,281; 14: 1,295; 15: 1,304; 16: 1,295; 17: 1,320; 18: 1,297
Federal 135 gr. Hydra- Shok JHP low recoilBBTI2: 909; 3: 976; 4: 1,039; 5: 1,085; 6: 1,113; 7: 1,136; 8: 1,145; 9: 1,161; 10: 1,167; 11: 1,166; 12: 1,184; 13: 1,183; 14: 1,182; 15: 1,194; 16: 1,185; 17: 1,207; 18: 1,194
Federal 105 gr. Expand'g FMJBBTI2: 985; 3: 1,073; 4: 1,140; 5: 1,194; 6: 1,235; 7: 1,258; 8: 1,278; 9: 1,307; 10: 1,314; 11: 1,318; 12: 1,273; 13: 1,343; 14: 1,372; 15: 1,364; 16: 1,358; 17: 1,381; 18: 1,370
Federal 124 gr. Hydra- Shok JHPBBTI2: 900; 3: 988; 4: 1,061; 5: 1,115; 6: 1,131; 7: 1,161; 8: 1,180; 9: 1,212; 10: 1,211; 11: 1,212; 12: 1,225; 13: 1,237; 14: 1,241; 15: 1,244; 16: 1,243; 17: 1,250; 18: 1,231
Federal 147 gr. Hydra- Shok JHPBBTI2: 837; 3: 902; 4: 951; 5: 1,007; 6: 1,030; 7: 1,040; 8: 1,047; 9: 1,055; 10: 1,067; 11: 1,059; 12: 1,081; 13: 1,081; 14: 1,090; 15: 1,090; 16: 1,073; 17: 1,096; 18: 1,083
Speer 124 gr. Gold Dot Short BarrelBBTI2: 1,074; 3: 1,108; 4: 1,203; 5: 1,259; 6: 1,284; 7: 1,316; 8: 1,329; 9: 1,345; 10: 1,338; 11: 1,360; 12: 1,361; 13: 1,378; 14: 1,390; 15: 1,375; 16: 1,379; 17: 1,400; 18: 1,395
100 gr Hornady FTX — factory referenceHornady 20264: 1,125

9mm Luger: factory velocity downrange

Distance (yd): velocity (fps). Source points and stated unit conversions; intermediate estimates are excluded.
Exact loadSource / publisherPublished points
70 gr Federal RHTFederal0: 1,625; 25: 1,457; 50: 1,312; 75: 1,190; 100: 1,096
100 gr Hornady FTX®Hornady0: 1,125; 50: 1,003; 100: 922
115 gr Federal FMJFederal0: 1,180; 25: 1,106; 50: 1,048; 75: 1,001; 100: 961
124 gr Federal FMJFederal0: 1,150; 25: 1,095; 50: 1,049; 75: 1,010; 100: 977
130 gr Federal TSJFederal0: 1,130; 25: 1,078; 50: 1,035; 75: 999; 100: 967
135 gr Federal HYDRA-SHOK DEEPFederal0: 1,060; 25: 1,026; 50: 996; 75: 970; 100: 946
138 gr Federal SHPFederal0: 1,050; 25: 989; 50: 940; 75: 899; 100: 862
147 gr Federal FMJ FPFederal0: 1,000; 25: 976; 50: 953; 75: 933; 100: 914
150 gr Federal TSJFederal0: 890; 25: 873; 50: 857; 75: 842; 100: 827
115 gr Federal JHPFederal0: 1,180; 25: 1,119; 50: 1,069; 75: 1,028; 100: 992
115 gr Federal JHPFederal0: 1,180; 25: 1,110; 50: 1,050; 75: 1,000; 100: 960
115 gr Federal FMJFederal0: 1,125; 25: 1,063; 50: 1,013; 75: 972; 100: 936
115 gr Hornady XTP®Hornady0: 1,155; 50: 1,038; 100: 958
115 gr Hornady FTX®Hornady0: 1,135; 50: 1,025; 100: 949
115 gr Hornady MonoFlex® +PHornady0: 1,100; 50: 1,005; 100: 937
124 gr Federal TMJFederal0: 1,120; 25: 1,070; 50: 1,028; 75: 993; 100: 961
124 gr Federal TSJFederal0: 1,050; 25: 1,011; 50: 978; 75: 949; 100: 922
124 gr Federal TSJFederal0: 1,150; 25: 1,064; 50: 1,000; 75: 949; 100: 907
124 gr Federal FMJFederal0: 1,090; 25: 1,052; 50: 1,019; 75: 991; 100: 965
124 gr Federal FMJFederal0: 1,260; 25: 1,187; 50: 1,126; 75: 1,074; 100: 1,032
124 gr Federal HYDRA-SHOKFederal0: 1,120; 25: 1,070; 50: 1,028; 75: 993; 100: 961
124 gr Federal HSTFederal0: 1,150; 25: 1,095; 50: 1,049; 75: 1,010; 100: 977
124 gr Federal HSTFederal0: 1,150; 25: 1,095; 50: 1,049; 75: 1,010; 100: 977
124 gr Federal HST +PFederal0: 1,200; 25: 1,136; 50: 1,083; 75: 1,039; 100: 1,002
124 gr Federal JHPFederal0: 1,150; 25: 1,095; 50: 1,049; 75: 1,010; 100: 977
124 gr Hornady FlexLock® +PHornady0: 1,175; 50: 1,081; 100: 1,012
124 gr Hornady XTP® +PHornady0: 1,175; 50: 1,074; 100: 1,001
124 gr Hornady XTP®Hornady0: 1,110; 50: 1,027; 100: 965
135 gr Hornady FlexLock® +PHornady0: 1,110; 50: 1,038; 100: 983
135 gr Hornady FlexLock®Hornady0: 1,010; 50: 960; 100: 918
138 gr Hornady DGH +PHornady0: 1,150; 50: 1,068; 100: 1,006
147 gr Federal TMJFederal0: 1,000; 25: 976; 50: 953; 75: 933; 100: 914
147 gr Federal TSJFederal0: 1,000; 25: 976; 50: 953; 75: 933; 100: 914
147 gr Federal FMJ MATCHFederal0: 900; 25: 883; 50: 866; 75: 851; 100: 836
147 gr Federal HSTFederal0: 1,000; 25: 976; 50: 953; 75: 933; 100: 914
147 gr Federal SOLID CORE +PFederal0: 1,120; 25: 1,082; 50: 1,048; 75: 1,019; 100: 993
147 gr Hornady XTP®Hornady0: 975; 50: 934; 100: 899
147 gr Hornady XTP®Hornady0: 975; 50: 934; 100: 899
124 gr Fiocchi JHPFiocchi0: 1,100
147 gr Fiocchi JHPFiocchi0: 975
147 gr Fiocchi FMJFiocchi0: 975
158 gr Fiocchi FMJFiocchi0: 850
147 gr Winchester Super Suppressed · FMJWinchester0: 990
147 gr Blazer Brass Clean-Fire Suppressor · TMJBlazer0: 900; 50: 766; 100: 734
147 gr Magtech Subsonic · FMJ flatMagtech0: 990
147 gr Magtech Subsonic · JHPMagtech0: 990
147 gr Magtech Polymatch · LPCMagtech0: 892
147 gr Aguila Subsonic · FMJ flat pointAguila0: 950; 100: 850
147 gr Remington Subsonic · flat nose enclosed baseRemington0: 950; 50: 927; 100: 907
140 gr Sellier & Bellot Subsonic · FMJSellier & Bellot0: 1,000.7; 27.3: 977.7; 54.7: 958; 109.4: 918.6
150 gr Sellier & Bellot Subsonic · FMJSellier & Bellot0: 1,000.7; 27.3: 984.3; 54.7: 967.8; 109.4: 938.3

How to interpret the comparison

Changing bullet weight also often changes bullet design and propellant choice. Two curves are comparisons of the listed products, not a controlled experiment proving that bullet weight alone caused the difference. Catalog downrange points are projections under the maker’s conditions; barrel-study points are recorded observations in the study firearm.

Direct answers

Common questions

What is 9mm Luger?

Also called 9×19mm or 9mm Parabellum, this is a rimless semiautomatic-pistol cartridge with extensive factory weight and construction options. Luger is the cartridge name; it does not limit the ammunition to Luger-brand pistols.

What diameter does 9mm Luger use?

The cited dimensional standard lists 0.3555 inches (9.030 mm), bullet maximum. This drawing convention is different from a casual caliber nickname.

Are similarly named cartridges interchangeable?

9mm Luger, .380 Auto, 9mm Makarov, and 9×21mm are different cartridges. +P is a separate pressure category; +P+ is not a SAAMI-standard pressure category.

Where is the 100-grain barrel curve?

The cited Hornady 100-grain Critical Defense Lite load is specified at 1,125 fps from a 4-inch barrel. The archive does not provide a comparable measured 100-grain barrel series. The graph therefore shows a single factory reference point when selected, rather than inventing an entire curve.

Are the graph values measured or estimated?

Factory datasets show manufacturer specifications and any published downrange projections. Chronograph and barrel-study datasets identify recorded measurements and the original test source. Dashed connectors and intermediate inspector values are labeled linear estimates; single source points are not extended into invented curves. Energy is calculated from bullet mass and velocity.

Does higher energy mean the best load?

Energy is calculated from mass and velocity. It does not establish accuracy, expansion, penetration, pattern density, recoil, or suitability for a particular firearm. Use the exact product documentation and firearm manual.

Trace the facts

Sources & methodology

Skives & petals: read the jacket construction →

Compiled by 2A Ledger from the linked standards, manufacturer publications, and identified test records. Checked October 18, 2026. Historical tests and older catalogs retain their original dates; a listing here does not establish current availability.

  1. SAAMI: dimensional drawing · PDF p. 33 ↗
  2. Sierra: 9mm Luger cartridge background ↗
  3. Federal · PDF p. 61 ↗
  4. Hornady · PDF p. 191 ↗
  5. Federal · PDF p. 60 ↗
  6. Ballistics by the Inch: archived measured barrel data (2020 archive) ↗
  7. BBTI: study index and source records ↗
  8. Additional factory specification / original test ↗
  9. Additional factory specification / original test ↗
  10. Additional factory specification / original test ↗
  11. Additional factory specification / original test ↗
  12. Additional factory specification / original test ↗
  13. Additional factory specification / original test ↗
  14. Additional factory specification / original test ↗
  15. Additional factory specification / original test ↗
  16. Additional factory specification / original test ↗

Diameter figures preserve the cited drawing convention. Inch–millimeter conversion uses exactly 25.4 mm per inch. Factory specifications describe the maker’s test setup; your firearm, ammunition lot, temperature, and measuring method can produce different results. This is an educational factory-ammunition reference, not a reloading manual.