The 10mm Auto is really two cartridges sold under one name. Some boxes are loaded mild, close to a hot 40 S&W. Others are loaded hot, with energy that rivals some magnum revolver loads. That spread is why 10mm ballistic gel results vary so much from one video to the next. This guide explains how to read 10mm ballistic gel tests, how load power changes what you see, and how the 10mm loads we carry compare on bullet design and listed speed.
We haven’t run our own gel tests. Every velocity and energy figure below comes from the linked product page.
A Short History That Explains the Spread
The 10mm Auto came out in the early 1980s. The FBI adopted it later that decade after a search for a stronger duty round. Agents found the full-power load hard to control, so the Bureau moved to a reduced-power version. That softer load led straight to the 40 S&W, which fires the same width bullet from a shorter case.
Today, ammo makers still split the 10mm in two. Mild factory loads sit at one end. Full-power loads from smaller boutique makers sit at the other.
Mild vs Full Power: Two Very Different Gel Tests
Compare two 180 grain FMJ loads. Federal American Eagle 180 grain lists 1,030 fps and 424 ft-lbs. Underwood 180 grain FMJ lists 1,300 fps and 676 ft-lbs. Same bullet weight, very different push.
In gel, more speed means a hollow point opens faster and wider. It can also mean the bullet breaks apart if it isn’t built for that speed. A mild load may act like a 40 S&W. A full-power load may act more like a magnum. Before you compare two 10mm ballistic gel tests, check what power level each load is.
Reading the Results
The FBI window
The FBI test standard looks for at least 12 inches of penetration and treats 18 inches as the upper end of the ideal range. Defense loads aim for that window. Many 10mm woods and hunting loads go well past 18 inches on purpose.
Expansion and retained weight
Fast hollow points open wide, but they need tough construction to stay in one piece. Bonded, solid copper and controlled-expansion bullets like the XTP are built for this. Check the recovered bullet. Did the jacket stay on? How much weight is left?
Test conditions
- Gel. Calibrated 10% ordnance gel is the reference. Clear synthetic blocks can differ.
- Clothing. Heavy fabric can plug a hollow point and make it act like a solid.
- Barrel. A long-slide 10mm and a compact can give quite different speeds.
- Shots. Look for five or more shots, not one perfect mushroom.
10mm Defense Loads Compared
These are the 10mm hollow point and defense loads in our range with listed speed and energy.
| Load | Bullet | Grain | Muzzle velocity (fps) | Muzzle energy (ft-lbs) | Pack |
|---|---|---|---|---|---|
| Federal HST 10mm 200 Grain JHP | Federal HST jacketed hollow point | 200 | 1,130 | 567 | 20-round box |
| Federal Punch 10mm 200 Grain JHP | Jacketed Hollow Point | 200 | 1,100 | 537 | 20-round box |
| Federal Power-Shok 10mm 200 Grain JHP | Jacketed Hollow Point | 200 | 1,110 | 547 | 20-round box |
| Sig V Crown 10mm 180 Grain JHP | Sig V-Crown jacketed hollow point | 180 | 1,250 | 624 | 20-round box |
| Sellier and Bellot 10mm JHP 180 Grain | Jacketed Hollow Point | 180 | 1,165 | 544 | 50-round box |
| Buffalo Bore Low Recoil 10mm 180 Grain JHP | Jacketed Hollow Point | 180 | 1,200 | 575 | 20-round box |
| Buffalo Bore 10mm 180 Grain JHP | Jacketed Hollow Point | 180 | 1,350 | 728 | 20-round box |
| Underwood 10mm 180 XTP Jacketed Hollow Point | Hornady XTP jacketed hollow point | 180 | 1,300 | 676 | 20-round box |
| Hornady 10mm 200 gr XTP JHP by Underwood | Hornady XTP jacketed hollow point | 200 | 1,250 | 694 | 20-round box |
| Underwood 155 Grain 10mm Hornady XTP JHP | Hornady XTP jacketed hollow point | 155 | 1,500 | 774 | 20-round box |
| Buffalo Bore 10mm 155 Grain TAC-XP Lead Free | Barnes TAC-XP solid copper hollow point | 155 | 1,350 | 627 | 20-round box |
| Underwood 10mm TAC-XP 155 Grain Lead Free | Barnes TAC-XP solid copper hollow point | 155 | 1,400 | 675 | 20-round box |
| Sellier and Bellot XRG 10mm 130 Grain Lead Free | Solid hollow point (lead-free) | 130 | 1,362 | 535 | 25-round box |
| Underwood Platinum Edition Xtreme Defender 10mm 115 Grain | Lehigh Xtreme Defense fluted solid copper | 115 | 1,700 | 738 | 20-round box |
Factory-power defense
Federal HST 200 grain lists 1,130 fps and 567 ft-lbs. Sig Sauer V-Crown 180 grain lists 1,250 fps and 624 ft-lbs. These sit in the middle of the 10mm range, with more push than 40 S&W but less blast than full-power loads.
Full-power hollow points
Underwood 180 grain XTP lists 1,300 fps and 676 ft-lbs, and Buffalo Bore 180 grain JHP lists 1,350 fps and 728 ft-lbs. The XTP is designed for controlled expansion at higher speed.
Lower recoil options
Buffalo Bore’s Tactical Low Recoil line tones things down. The Tactical Low Recoil 180 grain JHP lists 1,200 fps and 575 ft-lbs.
Solid copper and fluted
Buffalo Bore 155 grain Barnes TAC-XP uses a solid copper hollow point that can’t shed a jacket. Underwood Xtreme Defender 115 grain is a fluted, non-expanding design at 1,700 fps and 738 ft-lbs. Judge fluted bullets by depth and track width, not by expanded size.
Woods and Bear Loads
Gel is a weak model for bear defense. Bone and thick hide aren’t part of the test. For that job, look for heavy, hard cast or solid flat nose bullets that hold together and drive straight. Buffalo Bore Outdoorsman 220 grain lists 1,200 fps and 703 ft-lbs. Underwood 220 grain hard cast lists 1,200 fps and 704 ft-lbs. Buffalo Bore Dangerous Game 190 grain uses a solid wide flat nose. Hunting and carry rules vary, so check your state’s regulations first.
For more brand detail, see our Underwood 10mm ammo guide and Buffalo Bore 10mm ammo guide.
Practice Ammo
Full-power 10mm gets expensive and tiring fast. Many shooters practice with milder factory FMJ like Federal Champion 180 grain at 1,060 fps and 449 ft-lbs or Sellier & Bellot 180 grain FMJ at 1,164 fps and 543 ft-lbs. Then they finish each session with a few magazines of their carry load. Make sure your carry load runs well in your pistol.
Carry laws and hollow point rules vary. Check your state and local rules before you buy or carry defense ammo.
Shop 10mm Ammo
Browse our 10mm ammo for mild range FMJ, factory defense loads and full-power woods loads. Read each 10mm ballistic gel test with the power level in mind, and confirm your choice in your own gun.
Frequently Asked Questions
Is 10mm bigger than 45?
No. The 10mm fires a bullet about .40 inch wide, while the 45 ACP fires one about .45 inch wide. But 10mm usually runs much faster. Full-power 10mm loads list more energy than standard 45 ACP loads, with a flatter path and more recoil.
How big is 10mm?
The 10mm bullet is about .40 inch (10mm) wide. That is the same width as a 40 S&W bullet. The 10mm case is longer than the 40 S&W, so it holds more powder and can drive the bullet faster.
What Glock is 10mm?
Glock chambers 10mm Auto in the full-size Glock 20, the subcompact Glock 29, and the long-slide Glock 40. Check the slide marking on any used pistol to confirm the caliber before you buy ammo for it.
Is 10mm good for bear defense?
Many hikers carry 10mm in bear country because it offers more power than 9mm in a semi-auto pistol. For bears, pick a heavy hard cast or solid flat nose load built for depth, not a defense hollow point. Check local rules, and practice under stress.
Why do 10mm gel results vary so much?
10mm ammo comes in a wide range of power levels. A mild factory load and a full-power boutique load with the same bullet can show very different depth and expansion in gel. Barrel length and gel type also change results.
