Bullet drop compensation scopes (a.k.a. BDC reticles) became more popular recently.
Most people either love or hate it because it’s meant for use at a specific distance and in certain situations.
Others also believe other scope types are superior.
However, BDCs are an excellent option for people with specific needs on their weapons when it comes to range and accuracy requirements.
Here’s a complete guide about BDC reticles so that you can decide if you should get one and how to use it once you have it.
Contents
What is a BDC Reticle?
A bullet drop compensating reticle (BDC reticle) is a reticle pattern with a series of reference points along the vertical axis related to a bullet’s flight path.
Bullet drop depends on many factors like bullet weight, bullet type, caliber, and the gun’s velocity.
The objective of bullet drop compensation reticles is to keep the bullet’s impact on the target EVEN at greater distances.
Most BDC scopes shooters use guns with extended-range capabilities, like rifles. The farther the target, the more wind speed and bullet drop affect the shot.
Additionally, other factors like bullet weight, depending on the caliber used, can affect the trajectory too.
We’ll discuss compensating and adjusting for these things using a BDC rifle scope.
How to Use BDC Reticles
BDC scopes work through practice, steady aiming, and a bit of math involved in the process. Using the proper gun is important, too.
Muzzle velocity on a rifle is good enough for shooting at the ranges you should use the BDC reticle.
Tools You Need
Before using the scope, you need to prepare a few tools. You will need:
- The scope’s subtension sheet
- A ballistic calculator
The subtension sheet provides information about what the lines on the BDC reticle mean. Different manufacturers have varying dot reticle designs.
A BDC reticle is a series of vertical lines or “hash marks” methodically spaced apart. We’ll explain how these lines work together later.
Meanwhile, a ballistic calculator is used to calculate wind speed and other environmental factors.
These calculations are then used to help you adjust your positioning to make accurate shots.
Most BDCs don’t need a ballistic calculator, but it can help you get an idea of how to compensate for environmental factors.
Mapping the Reticle
Before tweaking anything else, you first need to ZERO the scope to the manufacturer’s recommended distance.
If you’re using similar ammunition to what the manufacturer used in the manual, move on to the next step.
However, if you want to use different ammo, check the manufacturer’s website for any charts or generators if you’re using a different ammunition type.
These will tell you how to adjust your scope.
However, this still isn’t ideal because each BDC reticle scope is sighted in for a specific caliber or bullet type.
REMEMBER: If you already know which caliber and ammo type you use, check the information on the BDC reticle before buying. There may be one natively sighted to that bullet.
Pressure, Humidity, Temperature, and Altitude
Long-range shooting doesn’t just involve bullet drop compensation; environmental factors affect how a bullet travels through the air.
For example, the air density might change even if you’re shooting in the same place throughout the year.
This can make your bullets slow down and drop more, affecting accuracy.
How would you adjust for these factors at once?
Manually doing the work would probably change the conditions before you can even shoot! This is where the ballistic calculator comes in handy!
Using density altitude in your ballistic calculator is the most convenient way to combine all environmental factors into one value.
The calculator then gives you suggestions on changing your positioning, which hash marks to use on the reticle, and how to angle your shot.
If you run the density altitude for a specific ammunition type, you will never be more than 1 MOA off your target, even at 600 yards.
Wind Speed
What about the obvious environmental factor?
Wind can be one of the most annoying things a shooter has to face when shooting at longer distances.
Unfortunately, the BDC reticle doesn’t have precise hash marks to compensate for wind. Even with this disadvantage, you can still try to be precise.
The best thing to do here is trial and error.
The wind will affect the bullet more with distance. The farther the target, the more you must aim toward where the wind comes from.
Here are some excellent examples to help illustrate this.
- Say you’re trying to hit a target out at 200 yards with a wind coming from the right. For this shot, you can try to move your aiming point slightly to the right of the reticle’s center.
- If you aim at a target out to 300 yards, you will have to move your point of aim more to the right and a bit higher than the center to still hit the target.
This is because the bullet drops, and the wind affects it more at extended ranges.
Logging Results and Trying Again
Don’t forget to log your results after each shot, even if you miss them!
This helps you gauge how your gun and caliber-specific bullet type perform at various ranges.
Moreover, recording HOW you aimed at a target and WHERE the impact points were will help you be more consistent in hitting shots at pre-determined distances.
Adjusting aiming points based on the point of impact is how you will learn to shoot accurately using a BDC reticle on your rifle.
The best way to record this is using a DOPE (Data On Previous Engagements) sheet. Keeping this with you every time you shoot is essential.
This consistency is what most shooters aim for, which comes with practice. Therefore, you need to keep trying again and again.
What Is a BDC Scope?
One of the popular choices for rifle scopes is the BDC scope. This can house a scope that contains a BDC reticle, which we discussed earlier.
However, some Bullet Drop Compensation scopes use