Stopping Power Calculator

Taylor KO Factor and Hatcher’s RSP for 2,795 factory loads. Pick one from the database or type your own numbers.

Stopping power

ImperialMetric

Bullet mass (gr)

Velocity (fps)

Diameter (in)

Bullet type

Taylor KO Factor

—

Hatcher’s RSP

—

Band (on TKO)

—

under 10 · 10–20 · 20–50 · over 50

Muzzle energy

—ft·lbf

Stopping power indices are simplified metrics — they do not model tissue damage, bullet expansion, or shot placement. Use as a rough comparison, not a terminal performance prediction. For material penetration modeling → Calculator.

TKO = mass_gr × velocity_fps × diameter_in ÷ 7000
RSP = energy_ft·lbf × area_in² × form factor
form factors are Hatcher’s own, 0.90 pointed to 1.25 wadcutter

Ranking — top 50 by Taylor KO

Out of 2,795 loads. Click a row to load it above.

#▲	Ammo▲	Caliber▲	Type▲	Mass (gr)▲	Velocity (fps)▲	Diameter (in)▲	TKO▲	Hatcher RSP▲
1	Hornady50 BMG 750 gr A-Tip® Match™	.50 BMG	BTHP	750	2,815	0.510	153.8	2,426.9
2	Kynoch.577 Tyrannosaur 750gr Woodleigh FMJ Solid	.577 Tyrannosaur	FMJ	750	2,460	0.577	152.1	2,635.9
3	Kynoch.577 Tyrannosaur 750gr Woodleigh SP	.577 Tyrannosaur	SP	750	2,460	0.577	152.1	2,767.7
4	Kynoch.600 Nitro Express 900gr Woodleigh FMJ Solid	.600 Nitro Express	FMJ	900	1,950	0.600	150.4	2,149.1
5	Kynoch.600 Nitro Express 900gr Woodleigh SP	.600 Nitro Express	SP	900	1,950	0.600	150.4	2,256.6
6	PMP.50 BMG 660gr FMJ	.50 BMG	FMJ	660	2,910	0.510	139.9	2,535.8
7	PMP.50 BMG 647gr AP Incendiary	.50 BMG	AP	647	2,910	0.510	137.2	2,237.3
8	Kynoch.577 Nitro Express 750gr Woodleigh FMJ Solid	.577 Nitro Express	FMJ	750	2,050	0.577	126.7	1,830.5
9	Kynoch.577 Nitro Express 750gr Woodleigh SP	.577 Nitro Express	SP	750	2,050	0.577	126.7	1,922.0
10	Aguila12 Gauge 875gr Minishell Slug	12 Gauge	SLUG	875	1,200	0.728	109.2	1,456.1
11	FederalPower-Shok Rifled Slug, 10 Gauge, 766 Grain, 3-1/2 in, 1280 fps	10 Gauge	SLUG	766	1,280	0.775	108.6	1,643.6
12	Kynoch.500 Jeffery 535gr Woodleigh FMJ Solid	.500 Jeffery	FMJ	535	2,400	0.500	91.7	1,343.9
13	Kynoch.500 Jeffery 535gr Woodleigh SP	.500 Jeffery	SP	535	2,400	0.500	91.7	1,411.1
14	FederalPower-Shok Rifled Slug, 12 Gauge, 547 Grain, 3 in, 1600 fps	12 Gauge	SLUG	547	1,600	0.728	91.0	1,618.3
15	Hornady500 Nitro Express 3" 570 gr DGS®	.500 Nitro Express	FMJ	570	2,150	0.500	87.5	1,149.0
16	Hornady500 Nitro Express 570 gr DGX® Bonded	.500 Nitro Express	SP	570	2,150	0.500	87.5	1,206.5
17	Kynoch.500 Nitro Express 570gr Woodleigh FMJ Solid	.500 Nitro Express	FMJ	570	2,150	0.500	87.5	1,149.0
18	Kynoch.500 Nitro Express 570gr Woodleigh SP	.500 Nitro Express	SP	570	2,150	0.500	87.5	1,206.5
19	PMP.500 Nitro Express 570gr ProAmm SP	.500 Nitro Express	SP	570	2,150	0.500	87.5	1,206.5
20	Weatherby.460 Weatherby Magnum 500gr FMJ Solid	.460 Weatherby Magnum	FMJ	500	2,600	0.470	87.3	1,302.4
21	Weatherby.460 Weatherby Magnum 500gr SP	.460 Weatherby Magnum	SP	500	2,600	0.470	87.3	1,367.6
22	Kynoch.505 Gibbs 525gr Woodleigh FMJ Solid	.505 Gibbs	FMJ	525	2,300	0.505	87.1	1,235.5
23	Kynoch.505 Gibbs 525gr Woodleigh SP	.505 Gibbs	SP	525	2,300	0.505	87.1	1,297.3
24	PMP.505 Gibbs 525gr ProAmm FMJ Solid	.505 Gibbs	FMJ	525	2,300	0.505	87.1	1,235.5
25	FederalPower-Shok Rifled Slug, 12 Gauge, 547 Grain, 2-3/4 in, 1520 fps	12 Gauge	SLUG	547	1,520	0.728	86.5	1,460.5
26	FederalSafari Swift A-Frame, 500 Nitro Express, 570 Grain, Swift A-Frame, 2100 fps	.500 Nitro Express	SP	570	2,100	0.500	85.5	1,151.0
27	FederalSafari Woodleigh Hydro Solid, 500 Nitro Express, 570 Grain, Woodleigh Hydro Solid, 2100 fps	.500 Nitro Express	FMJ	570	2,100	0.500	85.5	1,096.2
28	Winchester1 1/8gr Rifled Slug Deer Season	12 Gauge	HP	492	1,600	0.728	81.9	1,280.9
29	Weatherby.460 Weatherby Magnum 450gr Barnes TSX	.460 Weatherby Magnum	SP	450	2,700	0.470	81.6	1,327.3
30	Winchester1gr Rifled Slug Super X	12 Gauge	SP	437	1,760	0.728	80.0	1,314.0
31	FederalTruBall Rifled Slug, 12 Gauge, 438 Grain, 3 in, 1700 fps	12 Gauge	SLUG	438	1,700	0.728	77.4	1,462.8
32	FederalSafari Trophy Bonded Bear Claw, 458 Lott, 500 Grain, Trophy Bonded Bear Claw, 2300 fps	.458 Lott	SP	500	2,300	0.458	75.2	1,016.2
33	FederalSafari Trophy Bonded Sledgehammer Solid, 458 Lott, 500 Grain, Trophy Bonded Sledgehammer Solid, 2300 fps	.458 Lott	SP	500	2,300	0.458	75.2	1,016.2
34	Hornady458 Lott 500 gr DGS®	.458 Lott	FMJ	500	2,300	0.458	75.2	967.8
35	Hornady458 Lott 500 gr DGX® Bonded	.458 Lott	SP	500	2,300	0.458	75.2	1,016.2
36	PMP.458 Lott 500gr ProAmm FMJ Solid	.458 Lott	FMJ	500	2,300	0.458	75.2	967.8
37	PMP.458 Lott 500gr ProAmm SP	.458 Lott	SP	500	2,300	0.458	75.2	1,016.2
38	Kynoch.450 Rigby 480gr Woodleigh FMJ Solid	.450 Rigby	FMJ	480	2,375	0.458	74.6	990.7
39	Kynoch.450 Rigby 480gr Woodleigh SP	.450 Rigby	SP	480	2,375	0.458	74.6	1,040.2
40	FederalSafari Woodleigh Hydro Solid, 458 Lott, 500 Grain, Woodleigh Hydro Solid, 2250 fps	.458 Lott	FMJ	500	2,250	0.458	73.6	926.2
41	FederalPower-Shok Rifled Slug, 12 Gauge, 438 Grain, 2-3/4 in, 1610 fps	12 Gauge	SLUG	438	1,610	0.728	73.3	1,312.0
42	FederalTruBall Rifled Slug, 12 Gauge, 438 Grain, 2-3/4 in, 1600 fps	12 Gauge	SLUG	438	1,600	0.728	72.9	1,295.8
43	Hornady12 GA American Whitetail® 1 Ounce Rifled Slug	12 Gauge	SLUG	438	1,600	0.728	72.9	1,295.8
44	Winchester1gr Rifled Slug Rifled Slug	12 Gauge	SLUG	437	1,600	0.728	72.7	1,292.8
45	Winchester1gr Solid Expansion Sabot Slug BXS Shotshell Deer	12 Gauge	HP	437	1,600	0.728	72.7	1,137.7
46	FederalSafari Trophy Bonded Bear Claw, 470 Nitro Express, 500 Grain, Trophy Bonded Bear Claw, 2150 fps	.470 Nitro Express	SP	500	2,150	0.470	72.2	935.1
47	FederalSafari Trophy Bonded Sledgehammer Solid, 470 Nitro Express, 500 Grain, Trophy Bonded Sledgehammer Solid, 2150 fps	.470 Nitro Express	SP	500	2,150	0.470	72.2	935.1
48	Hornady470 Nitro Express 500 gr DGS®	.470 Nitro Express	FMJ	500	2,150	0.470	72.2	890.6
49	Hornady470 Nitro Express 500 gr DGX® Bonded	.470 Nitro Express	SP	500	2,150	0.470	72.2	935.1
50	Kynoch.470 Nitro Express 500gr Woodleigh FMJ Solid	.470 Nitro Express	FMJ	500	2,150	0.470	72.2	890.6

50 of 2,795 loads

Shot loads are not in this ranking. 537 of them carry the whole payload as one mass and the bore as their only diameter, so both formulas score nine pellets as a single 0.73-inch projectile. Left in, 39 of the top 50 were buckshot and the table stopped being about projectiles. Slugs, which really are one projectile, are included.

Is 9mm enough? These indices answer a narrower question than the one people ask them: how much momentum or energy a bullet carries into a target of a given frontal area. What it does once it arrives — through a windscreen, a car door, a wall — is the penetration calculator, and the recoil calculator is what it costs you to send it.