What Does Grain Mean in Ammunition?

The priority of beginner shooters is to learn the basics; gun safety, proper holds, gun parts, bullet parts, and how to operate a firearm. But as your experience grows and you go further into the world of shooters, you’ll inevitably come across some weird terms; powder weight, bullet weight, velocity, and more, and the interesting part is that most of those weird terms will be brought on to you in terms of grains. So today, we’ll discuss everything we can about grains, its use among the shooting community, and how it relates to your ammunition. By the time you’re finished with this article, you’ll understand what experienced shooters are saying and you’ll be speaking like one too. 

A Grain is essentially an obsolete unit of measuring mass. It was based on a single wheat grain or barley grain, and from that, it’s also used to measure other grains and seeds all over Europe. One grain is equivalent to 0.065 grams, 0.00014 pounds, or 0.0022 ounces. Or if you put it the other way, one ounce is equivalent to 437.5 grains, one gram is equal to 15.4 grains, and one pound is equal to 7000 grains.

It’s one of the earliest units used to measure mass, and do you know that grain helped to define the medieval English Inch? Yes, it’s weird that a unit of mass helped to define a unit of length, but it is true. 

As we move forward from the medieval period, grain has less and less use. Not only is it a very small unit of measurement, but it’s also somewhat inconsistent, and it’s only been properly defined in July 1959. Today, grains are only used in dentistry, archery, and of course, ammunition. 

What does grain mean in ammunition?

In firearms, grain is only used to describe ammunition parts. Now, once you talk or even watch an experienced shooter, you’ll hear them say something like “I’m shooting a 200-grain .45ACP round” or “I’ve got a 185-grain load.” Don’t get that wrong since that will most certainly mean that they are describing the bullet weight. It’s a bit confusing and dangerous as a beginner since you might think that they are describing their cartridge’s powder weight. Don’t get it wrong, shooters rarely talk about powder weight since that is a tricky topic to discuss, 5 grains of a certain powder brand might be extremely powerful or weak for another powder brand. So, if you’re considering going into reloading your own ammunition, that’s where you’ll encounter talking about powder weight, and remember to specify brand if you do. 

Another thing that grain applies to is if you’re shooting with a muzzleloader, you’ll use grain to measure both your black powder charge or bullet.

Why should you be concerned about bullet grain?

If you’re a beginner shooter, you don’t have to worry about grain, all you have to worry about is building your muscle memory. Now if you’re like me in the beginning, we’ll always choose the cheapest ammunition that’ll work like a charm, and the thing is, that’s perfectly fine. But did you ever notice that your accuracy might get poor if you change your ammo? The most probable culprit is that the bullet weight is different. That is only one of a couple of things that bullet weight affects. Here is everything that bullet weight affects:

Accuracy – A lot will change with your accuracy if you use a lighter or heavier bullet. The first thing that might change is how fast your bullet drops. If your target is far, we know that you have to slightly compensate by elevating your aim. Well, the general rule is that the heavier the bullet, the faster it drops its trajectory. But if you go the other way, light bullets also drop trajectory quickly. If your bullets are too heavy, it’s gravity that’ll pull them down. And if your bullet is too light, it’s their speed that’ll pull them down. Sure, lighter bullets generally have a faster speed at the muzzle allowing for a straighter trajectory, but a lighter object also has less inertia so wind and other forces will affect the lighter bullet faster. 

Light bullets also require less twist rate from the barrel while heavier bullets require more. Anything less than what a bullet needs will cause the bullet to destabilize and flip mid-air and will most likely result in keyholing (which is when a bullet hits a target on its side creating a keyhole-shaped hole). It’s important to note that most guides online say that heavy bullets destabilize more frequently, and while that’s true it’s also important to know that too light of a bullet will also be a problem. I said that here since I didn’t hear that when I was learning to shoot.

Velocity and power – These two things work together with your bullet weight. Lighter bullets will travel faster and penetrate better, but it’ll have lesser of a punch. On the other hand, heavier bullets will travel slower and be worse at penetrating but it’ll have more punch, and if it does penetrate, it’ll have a nastier entry and exit holes. 

Recoil – This is one of the most debated info I’ve seen in the shooting community. Which bullet produces more recoil, heavier or lighter? The general rule is that if gasses are released slower from the barrel, the less recoil you’ll have. And the heavier the bullet, the slower the speed it leaves from the barrel. So, do heavier bullets produce more recoil? Experienced shooters will beg to differ. 

To my knowledge, bullet weight does not play a part in recoil. It’s the amount of powder that a cartridge has. Heavier bullets will need less powder producing less recoil, while lighter bullets need more powder producing more recoil. So, if you want your recoil tweaked, it’s a complicated analysis between bullet weight and powder weight. As I said, powder weight is tough to compare between different brands. So, my general rule is Lighter bullets, more recoil.

How to choose what bullet grain to use

Choosing a bullet weight is not a straightforward answer since there is no one size fits all solution. It’s all about your preference. Go on buy a bunch of ammo and train yourself in a gun range, then once you shot a couple of magazines. Look for what you want to improve. And tweak as you go. 

Here are the things you can improve with changing your bullet weight and how to get your ideal bullet grain:

Accuracy – If you’re getting keyholes on your paper targets, you must get a bullet weight that will work within your barrel’s spin rate. Remember, heavier bullets require more spin rate to stabilize. While if you go too light, the bullet will be destabilized by air.

Velocity and Power – If you’re hunting and your bullet won’t make a clean wound, use a lighter bullet. If it doesn’t penetrate all the way, use a heavier one. 

Recoil – Improving recoil by using different cartridges is a tad complicated. Just remember, the less powder weight your cartridge has, the less recoil you’ll have. Because even though some people will say that changing bullet weight will affect your recoil, in the end, it will not. 

There you have it. While this guide and article are based on facts and experience, do take it with a grain of salt. Because in the end of the day, none of this will make sense to you unless you try different bullets yourself. Get the one that’ll work with your gun, and your situation and preference. Keep safe and have a good one! [sc name=”faq2questions” q1=”What does grain mean in ammunition?” a1=” Now, once you talk or even watch an experienced shooter, you’ll hear them say something like “I’m …” q2=”Why should you be concerned about bullet grain?” a2=”The most probable culprit is that the bullet weight is different. That is only one of a couple of things that bullet…” ][/sc]