July 28th, 2020

How Muzzle Velocity Changes with Different Barrel Twist Rates

applied Ballistics Barrel Twist rate velocity testing test bryan Litz
Many barrel-makers mark the twist rate and bore dimensions on their barrel blanks.

Does muzzle velocity change with faster or slower barrel twist rates? Absolutely, but much less than you might think. Faster twist rates do slow down bullets somewhat, but the speed loss is NOT that significant. With Bartlein .308 Win barrels of identical length and contour, a 1:12″-twist barrel was only 8 fps faster than a 1:8″-twist barrel. That was the result of testing by Applied Ballistics.

The Applied Ballistics team tested six (6) same-length/same-contour Bartlein barrels to observe how twist rate might affect muzzle velocity. This unique, multi-barrel test is featured in the book Modern Advancements in Long Range Shooting, Vol. 1. That book includes other fascinating field tests, including a comprehensive chronograph comparison.

applied Ballistics Barrel Twist rate velocity testing test bryan Litz

applied Ballistics Barrel Twist rate velocity testing test bryan Litz
Barrel Twist Rate vs. Velocity — What Tests Reveal
by Bryan Litz
When considering barrel twist rates, it’s a common belief that faster twist rates will reduce muzzle velocity. The thinking is that the faster twist rate will resist forward motion of the bullet and slow it down. There are anecdotal accounts of this, such as when someone replaces a barrel of one brand/twist with a different brand and twist and observes a different muzzle velocity. But how do you know the twist rate is what affected muzzle velocity and not the barrel finish, or bore/groove dimensions? Did you use the same chronograph to measure velocity from both barrels? Do you really trust your chronograph?

Summary of Test Results
After all the smoke cleared, we found that muzzle velocity correlates to twist rate at the average rate of approximately 1.33 FPS per inch of twist. In other words, your velocity is reduced by about 5 FPS if you go from a 1:12″ twist to a 1:8″ twist. — Bryan Litz

Savage Test Rifle with Six Bartlein Barrels
Barrel Twist Rate Velocity Modern Advancements Book Bryan Litz Applied Ballistics

Most shooters don’t have access to the equipment required to fully explore questions like this. These are exactly the kinds of things we examine in the book Modern Advancements in Long Range Shooting, Vol. 1. In that book, we present experiments conducted in the Applied Ballistics lab. Some of those experiments took on a “Myth Buster” tone as we sought to confirm (or deny) popular pre-conceptions. For example, here’s how we approached the question of barrel twist and muzzle velocity.

Six .308 Win Barrels from Bartlein — All Shot from the Same Rifle
We acquired six (6) barrels from the same manufacturer (Bartlein), all the same length and contour, and all chambered with the same reamer (SAAMI spec .308 Winchester). All these barrels were fitted to the same Savage Precision Target action, and fired from the same stock, and bench set-up. Common ammo was fired from all six barrels having different twist rates and rifling configurations. In this way, we’re truly able to compare what effect the actual twist rate has on muzzle velocity with a reasonable degree of confidence.

Prior to live fire testing, we explored the theoretical basis of the project, doing the physics. In this case, an energy balance is presented which predicts how much velocity you should expect to lose for a bullet that’s got a little more rotational energy from the faster twist. In the case of the .30 caliber 175 grain bullets, the math predicts a loss of 1.25 fps per inch-unit of barrel twist (e.g. a 1:8″ twist is predicted to be 1.25 fps slower than a 1:9″ twist).

Barrel Twist Rate Velocity Modern Advancements Book Bryan Litz Applied Ballistics

Above, data shows relationship between Twist Rate and Muzzle Velocity (MV) for various barrel twist rates and rifling types. From fast to slow, the three 1:10″ twist barrels are: 5R (canted land), 5 Groove, 5 Groove left-hand twist.

We proceeded with testing all 6 barrels, with twist rates from 1:8″ to 1:12″. After all the smoke cleared, we found that muzzle velocity correlates to twist rate at the average rate of approximately 1.33 fps per inch of twist. In other words, your velocity is reduced by about 5 fps if you go from a 1:12″ twist to a 1:8″ twist. [Editor: That’s an average for all the lengths tested. The actual variance between 1:12″ and 1:8″ here was 8 FPS.] In this case the math prediction was pretty close, and we have to remember that there’s always uncertainty in the live fire results. Uncertainty is always considered in terms of what conclusions the results can actually support with confidence.

Barrel Twist Rate Velocity Modern Advancements Book Bryan Litz Applied BallisticsThis is just a brief synopsis of a single test case. The coverage of twist rates in Modern Advancements in Long-Range Shooting Vol. 1 is more detailed, with multiple live fire tests. Results are extrapolated for other calibers and bullet weights. Needless to say, the question of “how twist rate affects muzzle velocity” is fully answered.

Other chapters in the book’s twist rate section include:
· Stability and Drag — Supersonic
· Stability and Drag — Transonic
· Spin Rate Decay
· Effect of Twist rate on Precision

Other sections of the book include: Modern Rifles, Scopes, and Bullets as well as Advancements in Predictive Modeling. This book is sold through the Applied Ballistics online store. Modern Advancements in Long Range Shooting is also available as an eBook in Amazon Kindle format.

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July 28th, 2020

Remington Arms Company Files for Bankruptcy (Again)

Remington Factory Bankruptcy chapter 11

Even with surging firearms sales in 2020, Remington Arms Company (Remington) found itself in financial trouble — with overwhelming obligations to creditors and investors. Accordingly, on July 27, 2020, Remington filed for Chapter 11 Bankruptcy — the second time in recent years.

Remington Factory Bankruptcy chapter 11

Remington, based in Madison, North Carolina, filed for Chapter 11 in March 2018. With major loan reorganizations, Remington “emerged nearly two months later, having converted more than $775 million in debt into equity for its lenders.” (Source: Syracuse.com.) However, despite this debt-restructuring, the company has struggled with high interest costs and litigation related to the 2012 Sandy Hook Elementary School shooting. The perpetrator had a Bushmaster XM15-E2S rifle sold by Remington.

This time, there are more challenges — and it’s unclear how the company’s operations will fare in the months and years ahead. According to the Wall Street Journal, the debt-burdened firearms maker will seek buyers for its assets:

Remington Arms Declares Bankruptcy Despite Surging Gun Demand
Firearms maker Remington Arms Co. filed for bankruptcy protection for the second time since 2018, weighed down by more debt than it can repay even as fearful Americans buy more guns than ever.

Remington … sought chapter 11 protection and will try to sell its business at a time when civil unrest and worries about personal safety have driven firearm sales to record highs.

The chapter 11 petition in the U.S. Bankruptcy Court in Decatur, Alabama, marks Remington’s second restructuring since 2018, when it filed for chapter 11 and transferred ownership to investors including Franklin Resources Inc. and JPMorgan Chase & Co.

Remington has been searching for potential buyers and was in talks to sell itself out of bankruptcy to the Navajo Nation before negotiations collapsed in recent weeks, leaving the company without a lead bidder, or stalking horse, in place.

The manufacturer’s firearms and ammunition businesses could be sold off separately, according to a person familiar with the matter.

Source: Wall Street Journal, Emphasis Added

Remington Factory Bankruptcy chapter 11

Remington Has a Storied History
Founded in 1816 by Eliphalet Remington in New York, Remington is the oldest continuously-operating gun manufacturer in the United States. Even with its present difficulties, Remington still sells more sporting rifles and shotguns than any other American company. Remington has developed more cartridges than any other U.S. company. And it is the only American company that sells firearms AND ammunition under its own name.

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July 28th, 2020

Rossi RS22 on Sale $109.99 — Surprisingly Good Budget Rifle

Rossi rs22 RS 22 .22 LR training rifle Mossberg

Looking for a very affordable first rifle for a young family member? Here’s one of the best low-cost options you can find among .22 LR rimfire rigs. The Rossi RS22 is a reliable, semi-auto rifle that comes equipped with barrel-mounted iron/fiber optic sights. There are also dovetails on the receiver for mounting scope rings. The RS22 also takes most Mossberg 702 magazines.

The Rossi RS22 features an 18″ free-floating barrel, adjustable fiber optic sights and a synthetic Monte Carlo stock. For added accuracy, 3/8″ dovetail mounts allow the mounting of a scope or other optic.

Rossi RS22 Specifications:

Model: RS22 Semi-Auto, .22 LR
Barrel: 18″ Free-floating
Stock: Black Monte Carlo Synthetic Stock
Overall Length: 36.25″
Weight: 4.1 lbs.
Scope Mount: 3/8″ Dovetail
Sights: Fiber Optic Front & Rear
Safety: Manual Cross-Bolt Safety
Magazine: 10-rd Detachable Box Mag


NOTE: The Rossi RS22 on sale has a matte black stock.

Rossi rs22 RS 22 .22 LR training rifle MossbergTwo Video Reviews of Rossi RS22
The above video review of the Rossi RS22 confirms its reliability and build quality. The reviewer praised the fiber-optic iron sights and liked the magazines. After fitting a scope to the rifle’s built-in dove-tail, the tester got excellent accuracy with CCI ammo at 25 yards. Ten shots basically formed one half-inch hole. (See video 8:24 – 8:50 and target at right.) That’s good enough for an NRL22 match. Pretty impressive for a $110 rifle!

Gunblast.com also tested the Rossi RS22. This “dandy little rifle” performed great, with flawless semi-auto feeding and cycling for hundreds of rounds. Accuracy was quite good. The tester praised the fit and feel of the stock and noted it has sling swivel studs and well-protected sights. The RS22 can also use 25-round Mossberg magazines.

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