Buckshot vs birdshot comes down to pellet size, because both are loads of round pellets in a shotshell. Birdshot pellets are small. Buckshot pellets are large. By Federal Premium’s size chart, the biggest birdshot pellet (size T) is .20 inch across, and the smallest standard buckshot pellet (No. 4 buck) is .24 inch across. Everything below that line is birdshot, and everything at or above it is buckshot.
This post walks through the size numbers, how choke affects a shot pattern, the other kind of shotshell load called a slug, and what to check before you buy. It is general information about how ammunition is made and sold.
Buckshot vs Birdshot: The Size Chart
Federal publishes a chart of shot sizes. The numbers run backwards from what you might expect. A bigger number means a smaller pellet, just like shotgun gauge.
Birdshot sizes (pellet diameter, inches), from Federal’s chart:
| Size | Diameter |
|---|---|
| T | .20 |
| BBB | .19 |
| BB | .18 |
| 1 | .16 |
| 2 | .15 |
| 3 | .14 |
| 4 | .13 |
| 5 | .12 |
| 6 | .11 |
| 7 | .10 |
| 7 1/2 | .095 |
| 8 | .09 |
| 8 1/2 | .085 |
| 9 | .08 |
| 10 | .07 |
Buckshot sizes (pellet diameter, inches), from Federal’s chart:
| Size | Diameter |
|---|---|
| No. 4 | .24 |
| No. 3 | .25 |
| No. 2 | .27 |
| No. 1 | .30 |
| No. 00 (double ought) | .33 |
| No. 000 (triple ought) | .36 |
Source: Federal Premium, Shotshell Ammunition Basics.
Notice the two scales are split. Birdshot is numbered with plain numbers, with a few letters at the large end. Buckshot is numbered the opposite way, so No. 000 is bigger than No. 00, which is bigger than No. 1. If you mix up the two scales you can misread a box. When in doubt, read the whole label, which also says the gauge, shell length and pellet type.
What the Numbers Tell You
Pellet size is the first thing the label tells you, but it is not the only thing. Three details matter before you buy:
- Gauge. The shell has to match the gun. Our post on 12 gauge vs 20 gauge covers what the number means and why mixing gauges is dangerous.
- Shell length. Shells come in lengths from 1 3/4 to 3 1/2 inches, according to Federal. The chamber length of your gun decides which ones are safe to fire.
- Shot material. Federal lists shot made of lead, steel, bismuth and tungsten alloy. Material changes how pellets pattern, so read the label and the owner’s manual for your gun.
A buckshot shell holds a small number of large pellets. A birdshot shell holds a much larger number of small ones, because small pellets take up less room.
A box tells you more than most people notice. Take it one line at a time. First find the gauge, such as 12 or 20. Then find the shell length, written in inches. Then find the shot size, which will be a number for birdshot or a “buck” size for buckshot. Last, find the shot material, if it is listed. Put those four facts next to your gun’s barrel marking and its manual. If every line matches, you have the right shell for the gun. If one line is missing or unclear, set the box aside and ask before you load it.
Where Choke Comes In
Choke is the narrowing at the end of a shotgun barrel. Federal describes the three common ones as full, modified and improved cylinder. Its guide gives these general working ranges for how the shot pattern looks at distance:
| Choke | Federal’s description |
|---|---|
| Improved cylinder | Excellent for short range, up to 30 to 35 yards |
| Modified | Medium range, 25 to 40 yards |
| Full | Effective at long range, up to 50 to 55 yards |
Federal’s advice is to try different loads at different distances, because lead, steel, bismuth and tungsten all pattern differently in each choke. Patterning means shooting the shotgun at a sheet of paper to see where the pellets land.
Federal’s patterning steps are worth knowing even if you never do it yourself. Pick an area with a safe backdrop. Wear shooting glasses and hearing protection. Set up patterning paper at least 40 inches square and mark an aiming point near the center. Shoot at least five test patterns, each on a separate sheet. Then outline a 30 inch circle around the densest part of the pattern and check it for even spread.
Whether a choke is safe for a given load is a question for the gun’s owner’s manual and the shell’s label. Do not guess. If you are not sure what choke your gun has, or whether it can be changed, bring it in and ask. For what our gunsmithing covers, see our gunsmithing page.
Buckshot vs Birdshot vs Slugs
A third kind of shotshell load is the slug. A slug is one solid projectile instead of many pellets. Federal describes two main kinds:
- Rifled or “Foster” slugs have ribbing on the outside to help the slug stay stable in the bore. Federal says the rifled slug is recommended for smoothbore barrels.
- Sabot slugs have a lead or copper bullet inside a plastic sleeve that grips the rifling to give it spin. Federal says sabot slugs should only be used in rifled barrels.
The takeaway is that a slug, buckshot and birdshot are three different tools. The barrel type, whether smoothbore or rifled, changes which slug is right for your gun. Always check the barrel and the manual before you load a slug.
Safety Rules That Apply to All Shotshells
The Sporting Arms and Ammunition Manufacturers’ Institute (SAAMI) is the group that writes ammunition standards. Its handling guidelines say to use ammunition only as intended, in a firearm in good working order that is designed for it, and to make sure the designation on the ammunition matches the designation marked on the firearm’s barrel. Its example is a 12 gauge shotshell used in a shotgun marked 12 gauge. Read the full pamphlet here: SAAMI Recommendations for Safe Ammunition Storage and Handling.
The National Shooting Sports Foundation (NSSF) adds two rules in 10 Rules of Safe Gun Handling. Rule 5 says never use damaged or substandard ammunition. Rule 7 says all shooters should wear protective shooting glasses and some form of hearing protection while shooting.
A short checklist you can use every time:
- Check the gauge on the barrel and the box.
- Check the shell length against the chamber.
- Read the pellet type and size on the label.
- Look over each shell for dents, corrosion or damage before it goes in the gun.
- Wear eye and ear protection.
Next Step at Lakeside
Not sure which shotshell goes with your gun? Bring the gun in or tell us the make and model, and we will read the barrel markings with you and show you what is on the shelf. You can also send us a message before you visit. For more about the store, see our home page.
