In order to shoot accurately, the shooter, the gun, and the ammunition all need to do their job! Recently, while at Gordy Gritters’ Precision Rifle Building class, I sat down and talked with Gordy in-depth about factors that contribute towards a rifle’s accuracy. A great discussion, and I hope you learn a lot from it!
Rifle Accuracy Factors: Gordy’s Short-List
With so many possible avenues to explore for increased accuracy, it’s helpful to start with the most important factors. Here’s Gordy’s list (not necessarily in order).
A good trigger is paramount for accurate shooting. Unless your rifle is bolted down, it will move somewhat as the trigger is pulled. A skilled marksman and the right equipment can make a big difference here, but the trigger will make a big impact on group sizes, and on your confidence level depending on what kind of shooting you’ll be doing.
A couple simple things to think about here are:
- Using a quality trigger that works well
- Adjusting the trigger for the type of shooting you’ll be doing
As Gordy mentioned in the video, you don’t want a 1lb trigger pull when shooting in the cold with bulky gloves, and you don’t want a 3lb trigger when competing in a Benchrest match. A good question to ask is: Are you controlling the gun, or is the gun controlling you?
Below is a TriggerScan graph that shows how a trigger behaves when set to different pull weights (see full story HERE):
The quality and specifications of a rifle’s barrel will have a direct effect on the precision you get out of that rifle. Match grade barrels use top-grade steel, precise manufacturing methods, special processes (like cryogenic treatment), and final checks like air gauging and/or hand-lapping. You can check the consistency of your barrel’s bore by “slugging” it and feeling for tight/loose spots. With this method you can easily detect changes in bore dimensions of 0.0001″ or even less! The gunsmith can also affect the performance of a barrel during machining. How internal stresses in the barrel steel are dealt with can have a big affect on accuracy.
3: Muzzle Crown
The crown on your barrel’s muzzle is the “final guiding surface” for the bullet before it begins its flight path. If your crown is not perfect, your accuracy can degrade, so it is worth checking and addressing!
4: Bedding (Barreled Action to Stock)
The interface between your rifle’s action/barrel and the stock is super-important for accuracy. Any stresses in the action can cause barrel vibrations, and the bedding is one of the common culprits for this important factor. A glass bedding or epoxy bedding job can really help prevent these types of issues from robbing precious accuracy. Bedding creates a stress-free and solid interface between the barreled action and the stock, and that is what you want!
5: Bolt Lug Contact
With chamber pressures of 50,000 – 60,000 PSI inside the chamber, the forces at play when firing a rifle are staggering. In order to prevent unwanted barrel vibration/movement while the rifle is fired, the bolt lugs must have good solid contact with the lug seats when the rifle is cocked and ready to fire (with everything in place). The bolt lugs WILL touch the seats when the rifle is fired. And that’s why uneven contact or gaps between the bolt lugs and seats will induce vibration and barrel movement. Since the barrel is hanging off the action, any off-axis forces will cause barrel whip, and that opens up your groups for sure!
Gordy “leaves no stone un-turned” when working on a rifle. When you’re helping to set world records, you can’t overlook any factor large or small. Here are some of the “secondary factors” that Gordy considers with regard to rifle accuracy:
- Firing pin protrusion and primer impact energy/consistency
- Scope mounting, lapping, bedding
And there are many more for sure! Whole books (many) have been filled discussing all of the possible factors, issues, and resolutions related to rifle accuracy. And that’s why it’s such a satisfying moment when everything comes together at the range or in the field. The quest for accuracy will propel people to great lengths to achieve their goals.
Here’s a link to some resources from the Extreme Accuracy Institute that will be super-helpful for those that want to learn more about rifle accuracy:
Extreme Accuracy Institute Classes, One-On-One Instruction
Gordy’s Gunsmithing DVDs and Books
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4 thoughts on “Rifle Accuracy Factors: A Discussion with Gordy Gritters”
Do you perhaps have a video on how to set a Dillon 750 XL machine showing how to adjust the primer
First, I hope you and your family had a great Christmas. It is fun to watch from afar the journey you are on. You and your videos/writing have contributed much to my learning about and understanding of accuracy, parts selection, build considerations and techniques, not to mention the intricacies of reloading.
As an aside, I am worried that you are going to leave me behind as you are going places with the channel that many of us can’t follow like fitting, threading and chambering barrel blanks and other work requiring large and sophisticated equipment and precision measuring tools.
That is not to say that I don’t find it extremely interesting as well as educational. I like to know and to be able to speak knowledgeably with the guys building rifles especially if one is for me!
I have watched Gordy’s video on chambering and look forward to future videos you publish based on the course you just attended. I am especially looking forward to learning about slugging the barrel for the purpose of getting an idea of its accuracy potential.
Please keep up the great work. Your videos are very enjoyable and contain a lot of usable information from some amazing industry experts. You are building a great legacy that will be enjoyed and appreciated for decades to come.
Thank you again.
Mentioned several times without explanation…. What is “slugging”?
You cast a slug in the bore, and push it through with a rod to “feel” tight and loose spots!