Data guide

Barrel Length vs Velocity: Chart and Data by Caliber

Name: Barrel length vs velocity by caliber
Creator: GunReleases
License: https://creativecommons.org/licenses/by/4.0/

How much does a shorter barrel slow a bullet? We compiled 80 loads in 21 calibers, from 2 to 28 inches, from three published tests: Ballistics By The Inch (BBTI), rifleshooter.com and Lucky Gunner. Every number is the tester’s. We added nothing.

By Cole Harlan, EditorData checked Nov 4, 2026How we verifyEditorial standardsCorrections

Barrel length vs velocity: the short answer

Longer barrels usually add velocity because the powder keeps burning and pushing the bullet for more of its travel. How much they add depends on the cartridge and the length. In BBTI’s tests, Federal 115 gr JHP 9mm measured 1094 fps at 4 in and 1295 fps at 16 in. Pistol rounds also flatten out: of the 49 pistol, revolver and rimfire loads BBTI measured at both lengths, 24 were no faster at 18 in than at 16 in (for example Federal 124 gr Hydra-Shok JHP: 1231 fps at 18 in, 1243 fps at 16 in). Rifles lose more per inch as the barrel gets very short: rifleshooter.com measured Federal M193 55 gr at 3431 fps from 26 in and 3187 fps from 16.5 in, then 3039 fps at 14 in and 2202 fps at 6 in.

Barrel length vs velocity by caliber

One row per caliber, using the first load on each page as the example. Open a caliber for the full chart, every load and a CSV. The “fps lost per inch” column is either the tester’s stated average or labeled as calculated from the cited points.

Barrel length vs velocity for 21 calibers. The example load is the first load on each caliber page. A dash means not tested/published at this length.
Caliber	Tested range	Example load	Velocity at published lengths	fps lost per inch	SAAMI test barrel	Typical uses
9mm Luger	2 to 18 in	Federal 115 gr JHP	3 in: 1029 fps 4 in: 1094 fps 5 in: 1166 fps 16 in: 1295 fps	18 to 16 in: 1.0 (calculated from cited points) 16 to 4 in: 16.8 (calculated from cited points) 4 to 2 in: 73.0 (calculated from cited points)	4.000 in	Carry and duty pistols; pistol-caliber carbines
.380 ACP	2 to 18 in	Speer 90 gr Gold Dot	3 in: 958 fps 4 in: 1052 fps 5 in: 1093 fps	18 to 16 in: 0.0 (calculated from cited points) 16 to 4 in: 13.8 (calculated from cited points) 4 to 2 in: 100.0 (calculated from cited points)	3.750 in	Pocket and micro-compact carry pistols
.40 S&W	2 to 18 in	Federal 180 gr JHP	3 in: 962 fps 4 in: 1016 fps 5 in: 1047 fps 16 in: 1142 fps	18 to 16 in: 11.5 (calculated from cited points) 16 to 4 in: 10.5 (calculated from cited points) 4 to 2 in: 55.5 (calculated from cited points)	4.000 in	Duty and full-size pistols; carbines
.357 SIG	2 to 18 in	Cor Bon 115 gr JHP	3 in: 1373 fps 4 in: 1491 fps 5 in: 1578 fps 16 in: 1768 fps	18 to 16 in: 1.0 (calculated from cited points) 16 to 4 in: 23.1 (calculated from cited points) 4 to 2 in: 134.5 (calculated from cited points)	4.000 in	Duty and carry pistols
.45 ACP	2 to 18 in	Federal 230 gr Hi-Shok JHP	3 in: 758 fps 4 in: 814 fps 5 in: 843 fps 16 in: 919 fps	18 to 16 in: -15.5 (calculated from cited points) 16 to 4 in: 8.8 (calculated from cited points) 4 to 2 in: 52.5 (calculated from cited points)	5.000 in	Full-size and compact pistols; carbines
10mm Auto	2 to 18 in	Federal 180 gr Hydra-Shok	4 in: 1013 fps 5 in: 1069 fps 6 in: 1093 fps 16 in: 1220 fps	18 to 16 in: 6.0 (calculated from cited points) 16 to 4 in: 17.2 (calculated from cited points) 4 to 2 in: 86.0 (calculated from cited points)	5.000 in	Full-size pistols and carbines
.38 Special	2 to 18 in	Cor Bon 110 gr JHP	2 in: 675 fps 4 in: 1013 fps 6 in: 1021 fps 16 in: 1298 fps	18 to 16 in: -27.5 (calculated from cited points) 16 to 4 in: 23.8 (calculated from cited points) 4 to 2 in: 169.0 (calculated from cited points)	7.710 in solid / 4.000 in vented	Revolvers, especially snub-nose carry guns
.357 Magnum	2 to 18 in	Federal 125 gr JHP	2 in: 949 fps 4 in: 1511 fps 6 in: 1702 fps 16 in: 2051 fps	18 to 16 in: 10.5 (calculated from cited points) 16 to 4 in: 45.0 (calculated from cited points) 4 to 2 in: 281.0 (calculated from cited points)	10.000 in solid / 4.000 in vented	Revolvers and lever-action carbines
.44 Magnum	2 to 18 in	Cor Bon 165 gr JHP	2 in: 952 fps 4 in: 1150 fps 6 in: 1321 fps 16 in: 1552 fps	18 to 16 in: 3.0 (calculated from cited points) 16 to 4 in: 33.5 (calculated from cited points) 4 to 2 in: 99.0 (calculated from cited points)	8.275 in solid / 4.000 in vented	Hunting revolvers and lever-action carbines
.45 Colt	2 to 18 in	Cor Bon 200 gr JHP +P	2 in: 675 fps 4 in: 875 fps 6 in: 1043 fps 16 in: 1245 fps	18 to 16 in: 15.0 (calculated from cited points) 16 to 4 in: 30.8 (calculated from cited points) 4 to 2 in: 100.0 (calculated from cited points)	7.260 in solid / 4.000 in vented	Revolvers and lever-action carbines
.22 LR	2 to 18 in	CCI Mini-Mag 40 gr CPRN	4 in: 1014 fps 6 in: 1101 fps 16 in: 1207 fps 18 in: 1212 fps	18 to 16 in: 2.5 (calculated from cited points) 16 to 4 in: 16.1 (calculated from cited points) 4 to 2 in: 79.0 (calculated from cited points)	24 in	Pistols, rifles and trainers
.22 WMR (.22 Magnum)	2 to 19 in	CCI Maxi-Mag 40 gr JHP	4 in: 1353 fps 6 in: 1575 fps 16 in: 1987 fps 18 in: 1985 fps	18 to 16 in: -1.0 (calculated from cited points) 16 to 4 in: 52.8 (calculated from cited points) 4 to 2 in: 203.5 (calculated from cited points)	24 in	Rimfire rifles, revolvers and pistols
5.56 NATO / .223 Rem (AR-15)	6 to 26 in	Remington UMC 55 gr FMJ	7 in: 2135 fps 10 in: 2489 fps 14 in: 2808 fps 16.5 in: 2968 fps 20 in: 3071 fps	26 to 16.5 in: 22.5 (tester’s stated avg) 16.5 to 14 in: 64.0 (calculated from cited points) 14 to 6 in: 106 (tester’s stated avg)	24 in	AR-15 rifles, carbines and short-barreled builds
.224 Valkyrie	16.5 to 28 in	Federal Fusion MSR 90 gr SP	16.5 in: 2561 fps 18 in: 2616 fps 20 in: 2621 fps 24 in: 2719 fps	28 to 16.5 in: 20.5 (tester’s stated avg)	24 in	AR-15 long-range and varmint rifles
7.62x39	16.5 to 24 in	Brown Bear 123 gr HP	16.5 in: 2301 fps 18 in: 2308 fps 20 in: 2361 fps 24 in: 2398 fps	24 to 16.5 in: 12.9 (tester’s stated avg)	20 in	AK-pattern rifles, SKS and bolt-action carbines
.300 Blackout	7.5 to 16.5 in	Winchester 200 gr Open Tip	7.5 in: 989 fps 10.5 in: 1048 fps 16.5 in: 1082 fps	16.5 to 10.5 in: 5.7 (calculated from cited points) 10.5 to 7.5 in: 19.7 (calculated from cited points)	16 in	Short AR-15 builds and suppressed rifles
.308 Win / 7.62 NATO	16.5 to 28 in	Winchester 147 gr FMJ	16.5 in: 2682 fps 18 in: 2739 fps 20 in: 2804 fps 22 in: 2837 fps 24 in: 2909 fps	28 to 16.5 in: 24.6 (tester’s stated avg)	24 in	Hunting, match and general-purpose rifles
6.5 Creedmoor	17 to 26 in	Hornady 147 gr ELD Match	18 in: 2502 fps 20 in: 2577 fps 22 in: 2638 fps 24 in: 2677 fps 26 in: 2728 fps	26 to 17 in: 26 (tester’s stated avg)	24 in	Long-range, match and hunting rifles
.243 Winchester	16 to 24 in	Remington 80 gr Core-Lokt PSP	16 in: 2806 fps 18 in: 2899 fps 20 in: 2965 fps 22 in: 3054 fps 24 in: 3123 fps	24 to 16 in: 39.6 (tester’s stated avg)	24 in	Deer and varmint hunting rifles
7mm Remington Magnum	20 to 28 in	Federal 150 gr Sierra GameKing BTSP	20 in: 2719 fps 22 in: 2766 fps 24 in: 2881 fps 26 in: 2939 fps 28 in: 2974 fps	28 to 20 in: 31.9 (calculated from cited points) 28 to 24 in: 23.2 (calculated from cited points) 24 to 20 in: 40.5 (calculated from cited points)	24 in	Long-range hunting rifles
.300 Winchester Magnum	16.25 to 24.25 in	Federal Gold Medal 190 gr SMK	16.25 in: 2575 fps 20.25 in: 2752 fps 24.25 in: 2892 fps	24.25 to 16.25 in: 39.6 (tester’s stated avg)	24 in	Long-range hunting and match rifles

All 21 caliber pages

Federal minimum barrel lengths

Federal law sets a floor. In 27 CFR 478.11, “Short-barreled rifle. A rifle having one or more barrels less than 16 inches in length…” A short-barreled shotgun is one with barrels “less than 18 inches in length.” The NFA definition of “firearm” in 27 CFR 479.11 uses the same lines: a shotgun barrel under 18 in and a rifle barrel under 16 in. The statute is 26 U.S.C. 5845. Read the rule itself at eCFR 27 CFR 478.11. For what changed in 2026, see our SBR rules for 2026 (state pages: Texas, Florida, California) and the state NFA checker. This is not legal advice.

Box velocity vs your gun: why barrel length changes velocity

Box velocities usually come from a standard test barrel, not a gun like yours. The SAAMI standards set those test barrel lengths. Z299.4 (centerfire rifle) says “All standard test barrels shall be 24 inches long” for exterior ballistics, with exceptions that include .300 AAC Blackout at 16 inches and 7.62x39 at 20 inches. Barrel length is measured muzzle to breech face. Z299.3 (centerfire pistol and revolver) sets velocity test barrels of 4.000 in for 9mm Luger, .40 S&W and .357 SIG; 5.000 in for 10mm Auto and .45 Auto; 3.750 in for .380 Auto; and solid or vented barrels for the revolver rounds: 10.000 in or 4.000 in for .357 Magnum, 7.710 in or 4.000 in for .38 Special, 8.275 in or 4.000 in for .44 Remington Magnum, and 7.260 in or 4.000 in for .45 Colt, with velocity measured at 15 ft. Z299.1 (rimfire) says “All standard rimfire rifle test barrels shall be 24 inches long.” That covers .22 LR and .22 WMR. SAAMI notes that your gun will not exactly duplicate test-barrel velocities. The full list is on the SAAMI standards page.

Measured examples: Hornady lists 2695 fps for its 6.5 Creedmoor 147 gr ELD Match from a 24 in test barrel, and rifleshooter.com measured 2677 fps at 24 in. Federal lists 2650 fps for its Gold Medal 168 gr SMK, and rifleshooter.com measured 2635 fps at 24 in. Hornady lists 2375 fps for its 110 gr V-MAX BLACK load from a 16 in test barrel, and Lucky Gunner measured 2376 fps from a 16.5 in barrel.

Barrel length vs velocity: “fps per inch” rules of thumb

You will see rules like “25 fps per inch.” Those are not measurements. The measured figures swing a lot. rifleshooter.com stated an average of 25.7 fps per inch for Federal M193 from 26 in to 16.5 in, but 104.6 fps per inch from 14 in to 6 in. For .308 Winchester it stated 20.9 to 24.6 fps per inch from 28 in to 16.5 in across its four loads. Our calculated pistol figures for Federal 115 gr JHP are 16.8 fps per inch from 16 in to 4 in and 73.0 from 4 in to 2 in. Use the table on each caliber page, not a rule.

For context only: Hornady’s ammunition FAQ says that on average, velocity gains or losses are approximately 25 to 35 feet per second per inch of barrel difference, and that this does not hold true for every load or every gun. That is a manufacturer’s general rule, not a measured chart, so it does not replace the tester data above. SAAMI is the standards body behind the test barrel lengths in the section above.

Calibers we did not chart, and why

12 gauge and other shotguns: Small Arms Review published a 2008 shotgun barrel cut-down test, but its inch-by-inch chart is no longer retrievable online and the article text gives only a few points, so we could not verify a full table.
.270 Winchester: we found only summary figures and forum posts, not a full published table.
.30-06 Springfield: we found no published inch-by-inch cut-down test with factory ammunition that we could verify.
.338 Lapua Magnum and 6mm Creedmoor: the rifleshooter.com cut-down tests we found used handloads; we chart factory ammunition only.
.22 ARC and .22 Creedmoor: no cut-down test with published data that we could verify. See our .22 ARC ammo guide, .22 Creedmoor ammo guide and .22 Creedmoor vs .22 ARC comparison.
Other BBTI calibers: BBTI also tested .44 Special, .41 Magnum, .327 Federal Magnum, .32 ACP, .25 ACP, .45 Super, .460 Rowland and 9mm Makarov. We have not added them yet.

Methodology and caveats

BBTI. Pistol, revolver, .22 LR and .22 WMR data come from Ballistics By The Inch. It used a Thompson/Center Encore pistol frame with custom barrels cut down 1 in at a time from 18 in to 2 in, fired three shots of each load at each length, and used two chronographs. Length is measured from muzzle to breech face. The Encore has no revolver cylinder gap, so revolvers will read lower. BBTI’s live site returned an error on Nov 4, 2026, so we link its method page and each test through the Internet Archive. BBTI is archived and has not been updated since 2020. The .380 test dates from 2010 and the .45 ACP test from 2008. The .22 WMR barrels started at 19 in.
rifleshooter.com. Rifle data come from 782 Custom Gunworks tests that cut a barrel down in steps (usually 1 in; 2 in for .243 Winchester) and measured with a MagnetoSpeed chronograph. We chart factory ammunition only, so handloads in the 7mm Rem Mag test are left out. The calibers used different rifles, so compare shapes, not single numbers across pages.
Lucky Gunner. The .300 Blackout data come from three different factory barrels (7.5 in, 10.5 in and 16.5 in), not one barrel cut down. Differences between lengths also include barrel-to-barrel variation. We show 7 of its 13 loads.
Limits. Testers used different rifles, chronographs and weather. Each number is a single test series, not a universal value. A dash means the tester did not publish that length; we never fill gaps.
Our part. We copied the published numbers exactly and calculated fps per inch only where a page labels it. The underlying measurements belong to the testers credited above; our compilation is CC BY 4.0.

Frequently asked questions

Does a longer barrel increase velocity?

Usually, up to a point. In BBTI's 9mm test, Federal 115 gr JHP measured 1094 fps at 4 in and 1295 fps at 16 in. But 24 of 49 pistol, revolver and rimfire loads were no faster at 18 in than at 16 in.

How much velocity do you lose per inch of barrel?

It changes with the load and the length, so one number does not fit. rifleshooter.com stated 25.7 fps per inch for Federal M193 from 26 in to 16.5 in and 104.6 fps per inch from 14 in to 6 in. For Federal 115 gr JHP in 9mm we calculate 16.8 fps per inch from 16 in to 4 in, from BBTI's published points.

What is the best barrel length for an AR-15?

No chart can name one. For Remington UMC 55 gr, rifleshooter.com measured 3071 fps at 20 in, 2968 fps at 16.5 in, 2808 fps at 14 in, 2489 fps at 10 in, 2135 fps at 7 in. A rifle with a barrel under 16 in is an NFA short-barreled rifle under federal law, so the shortest length you may build depends on paperwork and state law.

What is the minimum legal barrel length for a rifle?

Under federal law (27 CFR 478.11), a rifle with one or more barrels less than 16 inches long is a short-barreled rifle, and a shotgun with barrels less than 18 inches is a short-barreled shotgun. Both are NFA firearms. State law can add limits. This is not legal advice.

Why is my chronograph slower than the ammo box?

Published box velocities usually come from a test barrel, not a gun like yours. SAAMI sets 24 inches for rifle exterior ballistics (16 inches for .300 AAC Blackout, 20 inches for 7.62x39) and 4.000 in for 9mm Luger, 5.000 in for 10mm Auto and .45 Auto, 4.000 in for .40 S&W and .357 SIG, 3.750 in for .380 Auto, and, for revolver rounds, 10.000 in solid or 4.000 in vented for .357 Magnum, 7.710 in solid or 4.000 in vented for .38 Special, 8.275 in solid or 4.000 in vented for .44 Magnum, and 7.260 in solid or 4.000 in vented for .45 Colt. Your barrel, chronograph and ammo lot will differ. For example, Hornady lists 2695 fps for its 6.5 Creedmoor 147 gr ELD Match from a 24 in barrel, and rifleshooter.com measured 2677 fps at 24 in.

What is the best barrel length for a 9mm carbine or pistol?

It is a trade-off. In BBTI's test, 3 in measured 902 to 1245 fps, 4 in measured 951 to 1316 fps, 5 in measured 1007 to 1372 fps and 16 in measured 1073 to 1525 fps. A 9mm rifle with a barrel under 16 inches is an NFA short-barreled rifle.

Do shorter barrels change .300 Blackout subsonic loads?

Lucky Gunner measured subsonic loads from three different barrels. Hornady 190 gr Sub-X measured 1028 fps at 7.5 in, 1082 fps at 10.5 in, 1107 fps at 16.5 in. Lucky Gunner notes that two subsonic loads went past the speed of sound from the 16.5 in barrel.

Compare: 5.56 vs .223 · 6.5 Creedmoor vs .308 · 300 Blackout vs 5.56

Sources

Supplementary sources

News reports, advocacy groups, dealer practice and unofficial copies. They add context or report statements; the primary sources above control.

Cornell LII: 26 U.S.C. 5845, NFA definitions

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GunReleases.com (The Release Desk), “Barrel length vs velocity by caliber,” updated Nov 4, 2026. https://gunreleases.com/guides/barrel-length-velocity/

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