November 19th, 2019

The Mother of All Muzzle Brake Tests — PRB’s Epic Research

Cal Zant Precison Rifle Blog AccurateShooter Muzzle Brake Test Noise Recoil Reduction Video

Are you looking for a muzzle brake for your rifle? Then you MUST check out the epic Muzzle Brake Test performed a few seasons back by PrecisionRifleBlog.com. This massive, data-driven field test was organized by PRB head honcho Cal Zant. Over a period of months, Cal and his team tested 20+ muzzle brakes designed for 6mm, 6.5mm, and .30-caliber precision rifles. Hundreds of hours went into this research, which provided vital new insight and empirical data for several aspects of muzzle devices. Cal put a huge amount of labor/engineering into these tests and his findings deserve to be widely read.

Sound Level Test | Recoil Reduction Overview | Staying on Target | Muzzle Blast Test Results

Cal Zant Precison Rifle Blog AccurateShooter Muzzle Brake Test Noise Recoil Reduction VideoThe Muzzle Brake Overview Article covers designs, specs, and prices of 20+ brakes. Then separate, detailed PRB articles cover sound levels, recoil reduction results, ability to stay on target, muzzle blast/ground effects and more. SEE PRB Muzzle Brake Test Results SUMMARY.

GO TO PRB Muzzle Brake Test SUMMARY »

PRB muzzle brake test

Recoil Reduction
Cal created a system to directly measure the entire recoil force signature of each muzzle brake using high-speed sensors. Although the recoil cycle happens very quickly (around 1/100th of a second), his test equipment could record up to 1,000 force data points during a single recoil cycle! He fired over 1,000 rounds of match-grade ammo through four different rifles: 6XC, 6.5 Creedmoor, .308 Win, and the monster .300 Norma Magnum. He literally spent thousands of dollars on this part of the test, to ensure he got it right.

Cartridge Types Tested: 6XC, 6.5 Creedmoor, .308 Win, and .300 Norma Magnum

Cal Zant Precison Rifle Blog AccurateShooter Muzzle Brake Test Noise Recoil Reduction Video

Ability To Stay On Target
David Tubb helped Cal develop this part of the test, because David believes this is the most important aspect of a muzzle brake. Using a laser and high-speed camera, Cal was able to objectively quantify how well each design helped you stay on target.

Noise Level
Muzzle brakes are loud, but some are louder than others … three to four times as loud. Cal enlisted the help of an expert from the suppressor industry to precisely measure how much louder each muzzle brake made a rifle. Each brake was tested in accordance with MIL-STD-1474D using calibrated military-approved equipment, and the noise level was also tested at the shooter’s position.

Cal Zant Precison Rifle Blog AccurateShooter Muzzle Brake Test Noise Recoil Reduction Video

Recoil Reduction Summaries by Caliber
In the detailed summaries of recoil reduction test results, PRB provides hard data that might surprise a few people and even dispel a few myths. Particularly interesting is Zant’s comparison of recoil reduction with a suppressor compared to muzzle brakes. How do you think the suppressor performed compared to the brakes? You may be surprised.

Here are brake test findings for 6mm and 6.5mm. Click image for Test Results.

Cal Zant Precison Rifle Blog AccurateShooter Muzzle Brake Test Noise Recoil Reduction Video

Here are brake test findings for .308 Caliber. Click image for Test Results.

Cal Zant Precison Rifle Blog AccurateShooter Muzzle Brake Test Noise Recoil Reduction Video

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October 28th, 2019

Wow Factor: Muzzle Brake Blast Patterns Revealed

Precision Rifle Blog Muzzle Brake Test Blast Powder

A while back, the Precision Rifle Blog conducted a fascinating study of Muzzle Brakes. PRB figured out a way to show the actual “blast pattern” of gasses ejecting from the ports of muzzle brakes. The result was a fascinating (and eye-catching) series of images revealing the distinctive gas outflows of 20+ different types of muzzle brakes. If you are considering buying and installing a muzzle brake on your rifle, you should definitely review this important PRB Muzzle Brake Test.

GO to PRB Muzzle Brake Blast Pattern TEST PAGE »

For a prone shooter, particularly on dusty, dirty or sandy ground, muzzle blast is a major bummer. Muzzle blast can be very disturbing — not just for the trigger-puller but for persons on either side of the gun as well. Some muzzle brakes send a huge shockwave back towards the shooter, and others send blast towards the ground, kicking dirt and debris into the prone shooter’s face. If there was a way to illustrate those factors — shockwave and debris — that might help shooters select one brake design over another.

Precision Rifle Blog Muzzle Brake Test Blast Powder

Cal Zant at PrecisionRifleBlog.com applied a unique blend of creativity and resourcefulness to try to answer that question for 20+ muzzle brakes. Using high-speed photography and household products, he captured the blast pattern of 20+ different brake designs for easy side-by-side comparison. Can you figure out how Cal managed to show muzzle brake blasts so clearly? His “hi-viz” solution, revealed in the article, is very clever. See the eye-opening results for 20+ brakes, with illustrative photos, by visiting the Precision Rifle Blog Muzzle Brake Ground Signature Test Page.

Permalink - Articles, Tactical, Tech Tip 2 Comments »
July 6th, 2019

Don’t Roast Your Ammo — Watch Temps in Hot Summer Months

Heat Map USA color chart

Well folks, it’s July 6th already — the means we’re moving into “peak heat” summer conditions. It’s vitally important to keep your ammo at “normal” temps during the hot summer months. Even if you use “temp-insensitive” powders, studies suggest that pressures can still rise dramatically when the entire cartridge gets hot, possibly because of primer heating. It’s smart to keep your loaded ammo in an insulated storage unit, possibly with a Blue Ice Cool Pak if you expect it to get quite hot. Don’t leave your ammo in the car or truck — temps can exceed 140° in a vehicle parked in the sun.

Ammo cool storage

Bosch Insulated tool caseTo learn more about how ambient temperature (and primer choice) affect pressures (and hence velocities) you should read the article Pressure Factors: How Temperature, Powder, and Primer Affect Pressure by Denton Bramwell. In that article, the author uses a pressure trace instrument to analyze how temperature affects ammo performance. Bramwell’s tests yielded some fascinating results.

For example, barrel temperature was a key factor: “Both barrel temperature and powder temperature are important variables, and they are not the same variable. If you fail to take barrel temperature into account while doing pressure testing, your test results will be very significantly affected. The effect of barrel temperature is around 204 PSI per F° for the Varget load. If you’re not controlling barrel temperature, you about as well might not bother controlling powder temperature, either. In the cases investigated, barrel temperature is a much stronger variable than powder temperature.”

Powder Heat Sensitivity Comparison Test

Our friend Cal Zant of the Precision Rifle Blog recently published a fascinating comparison test of four powders: Hodgdon H4350, Hodgdon Varget, IMR 4451, and IMR 4166. The first two are Hodgdon Extreme powders, while the latter two are part of IMR’s Enduron line of propellants.

CLICK HERE to VIEW FULL TEST RESULTS

The testers measured the velocity of the powders over a wide temperature range, from 25° F to 140° F. Hodgdon H4350 proved to be the most temp stable of the four powders tested.

Precision Rifle Blog Temperature Stability test hodgdon varget H4350 Enduron IMR 4451

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February 23rd, 2019

PRS Gear Focus — Survey of Stocks and Chassis Systems

MPA Chassis PRS NRL modular BA aluminum

The MasterPiece Arms BA Chassis is a leading product choice according to a recent Precision Rifle Blog (PRB) survey of Precision Rifle Series (PRS) and National Rifle League (NRL) competitors. Second were Manners Stocks, and third were Foundation-brand systems. PRB Editor Cal Zant surveyed 150 PRS and NRL precision rifle shooters to determine what gear they run in long range rifle competitions. The MPA BA Competition Chassis ranked #1 with 27% of the PRS and NRL shooters surveyed running this particular modular chassis system. READ Full PRB Stocks and Chassis Survey.

MPA Chassis PRS NRL modular BA aluminum
Image courtesy of Precision Rifle Blog.

Here Are Links to Other PRB Equipment Surveys:

Barrels — What the Pros Use
Custom Actions — What The Pros Use
LR Scopes — What the Pros Use
Bipods & Tripods — What the Pros Use
Brakes & Suppressors — What the Pros Use
Custom Triggers — What the Pros Use

MPA BA Competition Chassis
MPA has several configurations of its highly successful BA Chassis System, with the MPA BA Competition Chassis named the Official Chassis of the 2019 PRS. This competition version includes all the standard features of the original, but includes special enhancements for long range tactical rifle competitions, such as the PRS and related events. There are additional hole locations on the fore-end for locating the rotating barricade stop, which locks the rifle in place when shooting on a variety of barricade designed stages. The spigot mount attaches to the front of the fore-end, giving the shooter additional space to mount their bipod. A bag rider attachment provides better rear bag recoil management (an Enhanced Bag Rider is available for an additional fee).

Masterpiece arms chassis systems PRS tactical

MPA president Phil Cashin is an active PRS shooter who finished in the top 100 in 2017 and qualified for the finale last year. Cashin, shown in the video below, regularly tests out new ideas and upgrades in actual competition and seeks out feedback from top tactical competitors. “It’s a great honor [for MPA] to be named the most popular brand of chassis/stock systems amongst the top PRS and NRL competitors[.] We look forward to developing even more products with the long-range precision shooter in mind,” said Cashin.

MPA masterpiece arms side folder

MPA Production Class Rifle
MPA also offers a PRS Production Class Rifle (PCR) using the MPA Chassis system mated to a Savage Model 12 action. Production Class rifles may cost no more than $2000.00 before optics. Designed specifically for the new PRS Production Class, MPA’s PCR Competition Rifle offers many premium features yet stays under the $2,000 Class limit. The Savage action is upgraded with a Rifle Basix 2-lb trigger, and the adjustable, modular chassis offers a bag rider, barricade stop, and built-in bubble level.

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July 12th, 2018

Muzzle Brake Noise Levels — What PRB Tests Reveal

PrecisionRifleBlog.com Cal Zant Muzzle Brake Test Noise Level Decibels Suppressor

A while back, Cal Zant at PrecisionRifleBlog.com did a big muzzle brake comparison test. Along with measuring recoil reduction, Cal’s team recorded sound levels in PRB’s exhaustive muzzle brake field test. In the PRB archives you’ll find comprehensive muzzle brake sound test results, with hard data on 20 different muzzle brakes.

Sound can be a tricky subject, but Cal Zant, the editor of PrecisionRifleBlog.com, presents everything an informed shooter should know about muzzle brake noise in a straightforward and practical way. Most sound tests are measured from the side of the muzzle, in accordance with mil-spec standards, and Cal did that. But he also measured the sound level of each brake from behind the rifle, closer to the shooter’s position. This provides a more accurate indicator of the actual sound levels firearms operators will encounter while shooting.

Muzzle brakes ARE really loud — that’s something most active shooters have observed. But this study finally gives us some hard data and makes objective comparisons. The difference between brakes was quite significant. Some brakes were ear-splitting — more than twice as loud as other brakes tested.

As a bonus, Cal also provides data on how the new Ultra series suppressors from Thunder Beast Arms Corp (TBAC) compare in terms of sound level behind the rifle.

Check out the Test Results: http://precisionrifleblog.com/2015/08/07/muzzle-brakes-sound-test.

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May 17th, 2018

Powder Temp Stability — IMR Enduron vs. H4350 and Varget

powder gunpowder temperature sensivity temp stability Hodgdon Extreme Varget H4350 IMR Enduron 4451 4166

A couple seasons back, PrecisionRifleBlog.com (PRB) published a significant field test of powder temperature stability. The test was designed to quantify the temperature stability of Hodgdon H4350 and Varget powders compared to IMR’s Enduron line of powders, specifically IMR 4166 and 4451. The results were very interesting, to say the least…

Hodgdon Extreme Series powders have attracted quite a fan base, with over 90% of the top shooters in the Precision Rifle Series choosing to run one of those powders. IMR offers a modern line of powders “with Enduron Technology” — which is also marketed to have “extreme temperature stability”. Sounds familiar! These new powders should compete directly with the Hodgdon Extreme Series, which gives shooters more temp-stable powder options to consider.

CLICK HERE to Read Full Powder Temperature Stability Test on Precision RifleBlog.com.

The top shooters in the PRS and veteran long-range shooters in other disciplines have learned to value a temperature-stable powder. That’s because a change in temperature can affect the trajectory or “flight path” of the bullet in two well-known ways:

1. Assuming all other environmental conditions remain the same, an increase in air temperature will cause a flatter trajectory due to a lower air density (easier for the bullet to cut through the air).

2. The same increase in temperature also causes the nitrocellulose-based powder inside the cartridge to burn at a higher rate, producing approximately four times the Point of Impact (POI) shift than just air temperature alone. (SEE: Temperature Effects On Zero on KestrelMeters.com.)

“The initial heat condition of your powder will affect the burn rate,” Bryan Litz explained at a recent Applied Ballistics Seminar. That means swings in ambient outside temperature can affect your internal ballistics, which will directly affect your muzzle velocity, which will change your bullet’s trajectory. Some powders are more affected by changes in temperature than others. So if your goal is first-shot hits and you may shoot in a variety of conditions — you should care about temperature stable powders.

The folks at PrecisionRifleBlog.com meticulously loaded 6.5×47 Lapua ammo with each powder using some of the best equipment available. This included the top-of-the-line Prometheus Gen II Powder Scale, which is capable of loading to the nearest kernel of powder. This ensured the powder charges were identical for each round of ammo. PRB’s testers explain the full set of equipment and steps in their loading process in the Full Test Report.

Magnetospeeed LabRadar chronograph chrono powder gunpowder temperature sensivity temp stability Hodgdon Extreme Varget H4350 IMR Enduron 4451 4166

Once they had a couple dozen rounds loaded with each powder, they went and shot them with each powder at 25° F, 65° F, and 140° F. The muzzle velocity of each shot was recorded using BOTH a LabRadar Doppler Radar and a MagnetoSpeed Chronograph. That provided two sets of velocity numbers. When placed and configured optimally, the LabRadar can measure muzzle velocity with +/- 0.1% accuracy, according to the manufacturer.

Here are the results from the PRB Powder Temp Stability Tests:

Magnetospeeed LabRadar chronograph chrono powder gunpowder temperature sensivity temp stability Hodgdon Extreme Varget H4350 IMR Enduron 4451 4166

You can see Hodgdon H4350 had the least variance in muzzle velocity, with just 25 fps over the 115° swing in temperature! That is very, very low. Hodgdon Varget was the second least temperature sensitive powder in this test, with 46 fps of variance in muzzle velocity between temperatures of 25° F and 140° F. IMR 4166 performed very similar to Varget, and proved to be fairly insensitive to large swings in temperature. IMR 4451 had the largest swing in muzzle velocity of the powders tested, but keep in mind just 68 fps over 115° F swing is still a good performance.

Most powders aren’t specially formulated to be temperature stable. So they would likely show much larger swings than what these four top-performing powders showed. However, Alliant’s relatively new Reloder 16 is an extremely temp-stable powder, with a burn rate that is a close match to H4350. Many F-Open competitors are now using Reloder 16 with considerable success.

PRB’s test team also noticed other interesting trends in the data. For example, variation in velocity does NOT appear to be linear across the full range of temperatures. By that, they mean the change per degree from 20° to 65° might be smaller or larger than the change per degree from 65° to 140°.

PRB’s testers talk about those things, provide a few other insightful views of the data, and discuss tools that can help you manage temp/muzzle velocity in the field in their full post. You can find that here: http://precisionrifleblog.com/2016/06/19/powder-temp-stability-hodgdon-extreme-vs-imr-enduron/

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July 1st, 2017

Smarter Shooter: Keep Your Ammo Cool on Hot Summer Days

Heat Map USA color chart

Well folks, it’s July 1st already — the means we’re moving into “peak heat” summer conditions. It’s vitally important to keep your ammo at “normal” temps during the hot summer months. Even if you use “temp-insensitive” powders, studies suggest that pressures can still rise dramatically when the entire cartridge gets hot, possibly because of primer heating. It’s smart to keep your loaded ammo in an insulated storage unit, possibly with a Blue Ice Cool Pak if you expect it to get quite hot. Don’t leave your ammo in the car or truck — temps can exceed 140° in a vehicle parked in the sun.

Ammo cool storage

Bosch Insulated tool caseTo learn more about how ambient temperature (and primer choice) affect pressures (and hence velocities) you should read the article Pressure Factors: How Temperature, Powder, and Primer Affect Pressure by Denton Bramwell. In that article, the author uses a pressure trace instrument to analyze how temperature affects ammo performance. Bramwell’s tests yielded some fascinating results.

For example, barrel temperature was a key factor: “Both barrel temperature and powder temperature are important variables, and they are not the same variable. If you fail to take barrel temperature into account while doing pressure testing, your test results will be very significantly affected. The effect of barrel temperature is around 204 PSI per F° for the Varget load. If you’re not controlling barrel temperature, you about as well might not bother controlling powder temperature, either. In the cases investigated, barrel temperature is a much stronger variable than powder temperature.”

Powder Heat Sensitivity Comparison Test

Cal Zant of the Precision Rifle Blog has published a fascinating temp-stability comparison test of four powders: Hodgdon H4350, Hodgdon Varget, IMR 4451, and IMR 4166. The first two are Hodgdon Extreme powders, while the latter two are part of IMR’s new Enduron line of propellants.

CLICK HERE to VIEW FULL TEST RESULTS

The testers measured the velocity of the powders over a wide temperature range, from 25° F to 140° F. Hodgdon H4350 proved to be the most temp stable of the four powders tested.

Precision Rifle Blog Temperature Stability test hodgdon varget H4350 Enduron IMR 4451

Permalink Bullets, Brass, Ammo, Reloading, Tech Tip 1 Comment »
October 14th, 2016

Rifle Training DVDs Reviewed by Precision Rifle Blog

Cal Zant Precision Rifle Blog PRB Training DVD Bryan Litz Tod Hardnett

PrecisionRifleBlog.com recently reviewed several video-based rifle training DVD sets. While instructional DVDs will never replace live “hands-on” training, they can be cost-effective ways to sharpen your skills. Watched periodically, these training DVDs can help reinforce the fundamentals.

PRB’s Editor Cal Zant has purchased several rifle training DVDs over the years. His recent Precision Rifle Blog DVD review looks at four different options:

Long Range Made Easy, Two-Volume Set, from Accuracy 1st
The Art Of The Precision Rifle, with Todd Hodnett (Magpul Dynamics)
Putting Rounds On Target, with Bryan Litz (Applied Ballistics)
Rifles Only — Precision Rifle Instructional DVDs, with Jacob Bynum

Cal reports that each of these four titles offers a slightly different approach, with each instructor displaying his own focus, based on his background and expertise.

Accuracy 1st’s Long Range Made Easy Two-Volume Set seemed to win PRB’s Editor’s Choice Award. The tagline on the DVD is: “Go from basic to advanced with the guy that has trained our best military snipers for the past 10 years.” That’s a pretty good description. Todd Hodnett is the primary instructor, and Bryan Litz joins him in several segments.

It’s the best of both worlds. Todd Hodnett’s pragmatic “the-bullet-cannot-lie” approach (field-proven by hundreds of the world’s best snipers), is combined with Bryan Litz’s engineering approach and vast knowledge of external ballistics verified with carefully recorded live-fire experiments. The two styles complement each other well, and provide an extremely well-rounded and comprehensive overview.

The DVD set is split into two volumes, each of which includes two discs. All together there are almost four hours of instruction from the most respected guys in the industry. And they cover a lot of ground — you’d never be able to cover this much in a one- or two-day live class. Plus with the DVD you can easily repeat an important point, and watch the whole program more than once.

Cal Zant Precision Rifle Blog PRB Training DVD Bryan Litz Tod Hardnett

Cal paid $76.95 out-of-pocket for the Long Range Made Easy, Vol. 1 & 2 Bundle, so his review wasn’t a paid advertisement. He thought this set provides a ton of value, and could help a lot of shooters. Here are key topics covered in Long Range Made Easy:

■ Advice for Gear Purchases
■ Optimal Gun Setup
■ Technique for Position
■ Simple & Quick Wind Formula

■ Using the Applied Ballistics Kestrel
■ Truing Ballistic Algorithms, Drag Scale Factoring, and Custom Drag Models
■ WEZ Analysis
■ Wind Course

If you’re new to the long range game, or you’ve been doing it for a few years and want to learn directly from some of the most sought-after instructors in the world, then check out Cal’s write-up over at PrecisionRifleBlog.com. CLICK HERE for PRB Review of Training DVDs.

Permalink - Videos, Shooting Skills, Tactical 2 Comments »
October 6th, 2016

Precision Rifle Blog Reveals Muzzle Brake Blast Patterns

Precision Rifle Blog Muzzle Brake Test Blast Powder

For a prone shooter, particularly on dusty, dirty or sandy ground, muzzle blast is a major bummer. Muzzle blast can be very disturbing — not just for the trigger-puller but for persons on either side of the gun as well. Some muzzle brakes send a huge shockwave back towards the shooter, and others send blast towards the ground, kicking dirt and debris into the prone shooter’s face. If there was a way to illustrate those factors — shockwave and debris — that might help shooters select one brake design over another.

GO to PRB Muzzle Brake Blast Pattern TEST PAGE

Precision Rifle Blog Muzzle Brake Test Blast Powder

Cal Zant at PrecisionRifleBlog.com applied a unique blend of creativity and resourcefulness to try to answer that question for 20+ muzzle brakes. Using high-speed photography and household products, he captured the blast pattern of 20+ different brake designs for easy side-by-side comparison. Can you figure out how Cal managed to show muzzle brake blasts so clearly? His “hi-viz” solution, revealed in the article, is very clever. See the eye-opening results for 20+ brakes, with illustrative photos, by visiting the Precision Rifle Blog Muzzle Brake Ground Signature Test Page.

Permalink - Articles, Tactical No Comments »
July 19th, 2016

Powder Temp Stability: IMR Enduron vs. Hodgdon Extreme

powder gunpowder temperature sensivity temp stability Hodgdon Extreme Varget H4350 IMR Enduron 4451 4166

PrecisionRifleBlog.com (PRB) recently published results from a field test PRB conducted to quantify the temperature stability of the popular Hodgdon H4350 and Varget powders and compare those to IMR’s new Enduron line of powders, specifically IMR 4166 and 4451.

Hodgdon Extreme Series powders have attracted quite a fan base, with over 90% of the top shooters in the Precision Rifle Series choosing to run one of those powders. IMR recently released a new line of powders “with Enduron Technology” — which is also marketed to have “extreme temperature stability”. Sounds familiar! These new powders should compete directly with the Hodgdon Extreme Series, which gives shooters more temp-stable powder options to consider.

CLICK HERE to Read Full Powder Temperature Stability Test on Precision RifleBlog.com.

The top shooters in the PRS and veteran long-range shooters in other disciplines have learned to value a temperature-stable powder. That’s because a change in temperature can affect the trajectory or “flight path” of the bullet in two well-known ways:

1. Assuming all other environmental conditions remain the same, an increase in air temperature will cause a flatter trajectory due to a lower air density (easier for the bullet to cut through the air).

2. The same increase in temperature also causes the nitrocellulose-based powder inside the cartridge to burn at a higher rate, producing approximately four times the Point of Impact (POI) shift than just air temperature alone. (SEE: Temperature Effects On Zero on KestrelMeters.com.)

“The initial heat condition of your powder will affect the burn rate,” Bryan Litz explained at a recent Applied Ballistics Seminar. That means swings in ambient outside temperature can affect your internal ballistics, which will directly affect your muzzle velocity, which will change your bullet’s trajectory. Some powders are more affected by changes in temperature than others. So if your goal is first-shot hits and you may shoot in a variety of conditions — you should care about temperature stable powders.

Magnetospeeed LabRadar chronograph chrono powder gunpowder temperature sensivity temp stability Hodgdon Extreme Varget H4350 IMR Enduron 4451 4166

The folks at PrecisionRifleBlog.com meticulously loaded 6.5×47 Lapua ammo with each powder using some of the best equipment available. This included the top-of-the-line Prometheus Gen II Powder Scale, which is capable of loading to the nearest kernel of powder. This ensured the powder charges were identical for each round of ammo. PRB’s testers explain the full set of equipment and steps in their loading process in the Full Test Report.

Once they had a couple dozen rounds loaded with each powder, they went and shot them with each powder at 25° F, 65° F, and 140° F. The muzzle velocity of each shot was recorded using both a LabRadar Doppler Radar and a MagnetoSpeed Chronograph. The LabRadar is a new type of device that allows you to measure muzzle velocity within at least +/- 0.1% of the reading.

Magnetospeeed LabRadar chronograph chrono powder gunpowder temperature sensivity temp stability Hodgdon Extreme Varget H4350 IMR Enduron 4451 4166

Here are the results from the PRB Powder Temp Stability Tests:

Magnetospeeed LabRadar chronograph chrono powder gunpowder temperature sensivity temp stability Hodgdon Extreme Varget H4350 IMR Enduron 4451 4166

You can see Hodgdon H4350 had the least variance in muzzle velocity, with just 25 fps over the 115° swing in temperature! That is very, very low. Hodgdon Varget was the second least temperature sensitive powder in this test, with 46 fps of variance in muzzle velocity between temperatures of 25° F and 140° F. IMR 4166 performed very similar to Varget, and proved to be fairly insensitive to large swings in temperature. IMR 4451 had the largest swing in muzzle velocity of the powders tested, but keep in mind just 68 fps over 115° F swing is still a good performance.

Most powders aren’t specially formulated to be temperature stable. So they would likely show much larger swings than what these four top-performing powders showed.

PRB’s test team also noticed other interesting trends in the data. For example, variation in velocity does NOT appear to be linear across the full range of temperatures. By that, they mean the change per degree from 20° to 65° might be smaller or larger than the change per degree from 65° to 140°.

PRB’s testers talk about those things, provide a few other insightful views of the data, and discuss tools that can help you manage temp/muzzle velocity in the field in their full post. You can find that here: http://precisionrifleblog.com/2016/06/19/powder-temp-stability-hodgdon-extreme-vs-imr-enduron/

Permalink - Articles, Gear Review, Reloading 7 Comments »
July 13th, 2015

Muzzle Brake Comparison Test by Precision Rifle Blog

Cal Zant Precison Rifle Blog AccurateShooter Muzzle Brake Test Noise Recoil Reduction Video

Another massive, data-driven field test has been completed by our friend, Cal Zant, over at PrecisionRifleBlog.com. The past few months, Cal has tested 20+ muzzle brakes designed for 6mm, 6.5mm, and .30-caliber precision rifles. Hundreds of hours have gone into this research, and it provides a lot of new insight and empirical data for several aspects of muzzle devices. Cal put a huge amount of labor/engineering into these tests and his findings deserve to be widely read.

CLICK HERE for PRB Muzzle Brake Test Overview | CLICK HERE for 6mm + 6.5mm Brake Test Results

PRB Muzzle Brake Test Methodology

Recoil Reduction
Cal created a system to directly measure the entire recoil force signature of each muzzle brake using high-speed sensors. Although the recoil cycle happens very quickly (around 1/100th of a second), his test equipment could record up to 1,000 force data points during a single recoil cycle! He fired over 1,000 rounds of match-grade ammo through four different rifles: 6XC, 6.5 Creedmoor, .308 Win, and the monster .300 Norma Magnum. He literally spent thousands of dollars on this part of the test, to ensure he got it right.

Cartridge Types Tested: 6XC, 6.5 Creedmoor, .308 Win, and .300 Norma Magnum

Cal Zant Precison Rifle Blog AccurateShooter Muzzle Brake Test Noise Recoil Reduction Video

Ability To Stay On Target
David Tubb helped Cal develop this part of the test, because David believes this is the most important aspect of a muzzle brake. Using a laser and high-speed camera, Cal was able to objectively quantify how well each design helped you stay on target.

Noise Level
Muzzle brakes are loud, but some are louder than others … three to four times as loud. Cal enlisted the help of an expert from the suppressor industry to precisely measure how much louder each muzzle brake made a rifle. Each brake was tested in accordance with MIL-STD-1474D using calibrated military-approved equipment, and the noise level was also tested at the shooter’s position. This produced some interesting results.

Cal Zant Precison Rifle Blog AccurateShooter Muzzle Brake Test Noise Recoil Reduction Video

Zant also includes high-res photos of each brake, and plans to publish other info about each model (including price, whether it requires gunsmithing, what calibers it is available in, etc.) to make it easy to compare them side-by-side.

Cal recently started publishing the results of these tests, and there is already a lot of interesting info. The data might surprise a few people and even dispel a few myths. Particularly interesting is Zant’s comparison of recoil reduction with a suppressor compared to muzzle brakes. How do you think the suppressor performed compared to the brakes? You may be surprised.

Here are brake test findings for 6mm and 6.5mm. Click image for Test Results.

Cal Zant Precison Rifle Blog AccurateShooter Muzzle Brake Test Noise Recoil Reduction Video

Here are brake test findings for .308 Caliber. Click image for Test Results.

Cal Zant Precison Rifle Blog AccurateShooter Muzzle Brake Test Noise Recoil Reduction Video

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