June 20th, 2018

Chrono Comparison Test: LabRadar, Magnetospeed, & Oehler 35P

labradar chronograph test magnetospeed V3 oehler 35P 6mmBR Ackley BRA

We see comparison tests of cars, cameras, and other hardware. But how about chronographs? What could we learn by setting up three different chronographs, and running a 20-shot string over all three at the same time. One of our Forum members, Randy S. (aka AAA) did that very test with three of the best chronographs you can buy: LabRadar, MagnetoSpeed, and an Oehler model 35P. The MagnetoSpeed was attached to the barrel of an F-Class rig, with the LabRadar placed on the left side of the shooting bench. The Oehler 35P was positioned about 23 feet downrange. The photo above shows the set-up. A 20-shot string was recorded with the results in a spreadsheet.

AAA talks about this interesting experiment in a Shooters’ Forum Thread. Here is his report:

Comparison Testing Three Chronographs

We all have our favorite chronograph. Each gives a number, but how would that number compare to the same round fired with another chronograph? I wanted to know so a friend and I set up the following test with three chronographs: LabRadar, MagnetoSpeed V3, and Oehler Model 35P.

For the test we fired Berger 105gr VLDs over the three chronographs simultaneously. The test rifle was my 6mm BR Ackley (BRA) F-class rig with fire-formed brass and 200 rounds on the new barrel.

Chronogaphs Tested
LabRadar
MagnetoSpeed V3
Oehler Model 35P
Temperature: 86 deg. F
Elevation: 854 feet
Cartridge: 6mm BRA (105gr Berger VLD)
Time between shots: 45 seconds

To start off, five rounds were fired to make sure all systems were recording and to warm the barrel. Then the test was 20 shots fired across all three instruments with 45 seconds between shots. The Oehler was set 7.5 yards from the muzzle so 12 FPS was added to the recorded value.

We were using the internal trigger on the LabRadar. The manual says the Vo indicated is the actual muzzle velocity when using the internal trigger, but not if using the Doppler. The 12 FPS Oehler adjustment (back to MV) was based on the Berger Ballistics Calculator.

Results of the Triple Chronograph Shoot-Out:

labradar chronograph test magnetospeed V3 oehler 35P 6mmBR Ackley BRA

LR-M is FPS variance between LabRadar and MagnetoSpeed V3. LR-O is FPS variance between LabRadar and distance-adjusted Oehler 35P. You can see all three chronos were very consistent. SD was identical with the LabRadar and MagnetoSpeed. CLICK HERE for spreadsheet.

The tester, Randy S. (aka AAA) says: “Judge for yourself, but I was impressed by all.”

Comments by Forum Members
Our Forum members expressed interest in this Triple Chronograph test. Some confirmed that the LabRadar and Magnetospeed give very similar FPS numbers, based on their own tests:

“Great test and thanks for sharing. I’ve tested my MagnetoSpeed and LabRadar together and results are always within 2-4 FPS of one another.” — Big D

“Very happy to see your numbers support my decision to buy a MagnetoSpeed. Had read reports comparing it to the Oehler and the numbers I get seem to be supported by my long range shooting results. Many thanks for taking the time and effort [to perform] this comparative test. Always good to get actual test results.” — Texas10

“I did a 4-shot test with my MagnetoSpeed and another shooter’s LabRadar a couple of days ago. The results were within 4 fps with the LabRadar being optimistic.” — Pat Miles

Forum Member Powderbreak studied AAA’s original spreadsheet from the chronograph trio test, then figured out the shot-by-shot FPS variance between the machines. He concluded that all the machines performed very well. Powderbreak posted:

Analyzing the Triple Chronograph Test — What Can We Conclude?

AAA did a great job of comparing the 3 chronos. What conclusions can be drawn?

1) I have not checked the manufacturer’s claims of accuracy, but the three chronos are very close to one another. There is no way for us to determine the actual true velocities, but we do not need to do so. Any of the chronos would be more than adequate for an accurate shooter.

2) The resolution of the three chronographs is actually pretty astounding. One foot per second (FPS) is a resolution of 0.033%.

3) AAA did a great job of reloading a very consistent round. With an extreme spread of 33 fps out of 3014 for 20 rounds, that is only 1.09% total spread of velocities.

4) There is a closer velocity match between the MagnetoSpeed and the LabRadar, but that does not mean the Oehler is less accurate. There is simply an offset between the Oehler and the other two. This could be due to the greater distance, the location, or the internal working of the Oehler.

5) Believe your chronograph, it is probably the most accurate reloading tool that you own.

Brian Litz of Applied Ballistics carefully explained the operation, set-up, accuracy and comparison of AB’s chronographs in his books. [Those books] are well worth the money, and give great insight into the workings of chronographs.” — Powderbreak

Permalink Bullets, Brass, Ammo, Gear Review, Tech Tip 6 Comments »
February 15th, 2018

Quarter-MOA, Half-MOA? How Much Precision Is Really Enough?

Jim See Elite Accuracy
This impressive 15-round group was shot by Jim See of Elite Accuracy.

Different shooting disciplines demand different levels of precision/accuracy. In the rapid-fire 3-Gun game, you could probably “clean” most stages with a 2-MOA rifle. By contrast, in the short-range group benchrest game, to compete with the best, you’ll need a rifle that shoots in the “ones” (i.e. 0.1-0.19 MOA) in perfect conditions. In 1000-yard F-Class competition, the top shooters want a rifle that will hold one-third-MOA of vertical at that distance.

What is your standard of accuracy? How good is “good enough”. Jim See, a skilled gunsmith and successful PRS competitor, has answered that question for his tactical discipline. For the kind of matches Jim shoots, he likes to have a rifle that will hold half-MOA for five (5) shots, 3/4-MOA for 15 shots, and 1 MOA for twenty shots. Remarkably, Jim’s rifle can do that with factory ammo. Above is an impressive 15-shot group shot with .260 Remington Federal Premium Ammo.

Jim See Elite Accuracy

“I say it all the time, my loads need to print 5 under 1/2″, 10 under 3/4″, and 20 under 1″. It’s simple, if a hot barrel will keep 20 rounds fired in succession under my standard it will be a good barrel and load for Precision Match Shooting. Federal Premium Gold Metal Match .260 with Sierra bullets made the cut for me today. 15 consecutive shots under 3/4 MOA.” –Jim See

It’s said that you “can never have too much accuracy”, but there are acceptable standards for each discipline, and they’re not the same. A 100/200 yard Benchrest shooter will be sorely disappointed with a rifle/ammo set-up that can only deliver half-MOA. On the other hand, a PRS competitor like Jim See can achieve great success with a lesser degree of precision. This means you can save time and money. You can run your barrels longer between cleanings, and you don’t have to go “full OCD” when loading your ammo. The PRS shooter does not need to weigh-sort primers, or load powder to single-kernel standards. Proof is the performance. Jim See recently took third place at the Spearpoint Shootout, and he has been a podium finisher at other events. Learn more about Jim’s gunsmithing and training operations at EliteAccuracy.com.

Download This Load Development Target

Jim’s target seemed a bit familiar. AccurateShooter.com created this Diamond and Dot Target a few years back. On each aiming point, there are high-contrast black horizontal and vertical lines for aligning your cross-hairs. The gray circle lets you see the bullet impacts above, without obliterating the red diamond, which is quite useful for precise aiming (we put fine cross-hairs on the points of the diamond). This target sheet includes data entry tables below each of the three aim points. There are many other free targets out there, but this format is very popular. We’re pleased to see Jim using it. You can download this and dozens of other FREE Targets from the AccurateShooter.com Target Page.

AccurateShooter precision load development free target

Permalink Reloading 4 Comments »
April 13th, 2015

MagnetoSpeed’s New $189.00 Sporter Chronograph

magnetospeed sporter chrono chronograph test review product speed bullet trajectory price sale
Sporter Chronograph Kit includes: Bayonet Sensor, 3.5 foot Data Cable, Remote Display (with Battery), Strap with thumb nut, Two V-block spacers, and compact storage box.

Magnetospeed has just introduced a new bayonet-style chronograph that is less than half the price of previous MagnetoSpeed models. This is big news for shooters who always wanted a MagnetoSpeed but found the $399.00 cost (for V3 model) too pricey. The new Sporter Chronograph will cost just $189.00. It offers most of the features of the more expensive models (see chart below for details) and has a updated sensor. The MagnetoSpeed Sporter chronograph kit was designed to be used on barrels from 1/2 inch up to 1 inch in diameter. In can also accommodate muzzle brakes and flash hiders up to 2.7 inches in length. MagnetoSpeed says its new Sporter is “Ideal for contoured rifle barrels (sporter barrels) and long-barreled revolvers.”

See $189.00 Sporter Chronograph Features Reviewed in Video

MagnetoSpeed Sporter features

  • Simple, one-button cycling display (shows recent shot velocity and statistics).
  • Three sensitivity settings for fine-tuning.
  • Easy access battery compartment, with 9V Battery included.
  • Integral, quick-attachment system, with metal buckle, nylon strap, screw-in tensioner, and dual V-block spacers (thick and thin).
  • Bayonet works with Muzzle Brakes and Flash-hiders up to 2.7″ long.

magnetospeed sporter chrono chronograph test review product speed bullet trajectory price sale

magnetospeed sporter chrono chronograph test review product speed bullet trajectory price sale

Q: Will the Sporter Chrono work with thicker barrel (i.e. greater than 1″ diameter)?

A: The manufacturer recommends the $399.00 V3 model for thicker barrels. But, wink-wink, if you have a 1.25″ barrel you can get this to work, based on what we’ve seen. If you need to go really fat (up to 2.0″ diameter), get the V3. Magnetospeed also says the V3 is needed for airguns, shotguns, and muzzleloaders.

Click Image for Full-Screen Photo
magnetospeed sporter chrono chronograph test review product speed bullet trajectory price sale

Permalink New Product, Reloading 8 Comments »
November 3rd, 2014

New Applied Ballistics Book Features Test Data for 400 Bullets

Applied Ballistics has just announced Ballistic Performance of Rifle Bullets. This new book is chock full of “mission critical” data on hundreds of popular projectiles. This latest reference book from Bryan Litz contains live fire test data on 400 modern rifle bullets. The data pages contained in this book are similar to the 225 bullet data pages found in Applied Ballistics for Long Range Shooting. The Ballistic Coefficient data is based on live fire testing methods which are repeatable within +/- 1%. If you’re looking for “rock-solid” info on the ballistic performance of today’s most popular rifle projectiles, this work is the definitive print resource. Scroll down to see a sample page from the new book.

Bryan Litz Bullet BookCLICK HERE to see the full list of bullets covered in this new resource book.

Visit the Applied Ballistics Online Store to pre-order your copy and save $5. Note: Pre-orders are expected to ship and arrive at USA destinations in time for Christmas. Retail price is $54.95, with a $5.00 pre-order discount.

More about the Book
“Modern rifles have reached an unprecedented level of accuracy. In many cases, the weak link in the chain of hitting targets is the trajectory modeling, which is based on bullet performance,” stated author Bryan Litz. Unfortunately, shooters can’t always rely on advertised Ballistic Coefficients (BCs) being accurate. Slight errors in BC modeling can be the cause of missing your target. Furthermore, a meaningful apples-to-apples comparison of bullet performance is not possible when the BCs are determined differently by various brands.

This book provides highly accurate ballistic performance data for 400 modern long range bullets from .224 to .408 caliber. By employing a common testing method for bullets of all brands, shooters are provided with consistent and accurate performance data which can be used to compare and select bullets, as well as to calculate accurate trajectories which put your shots on target at long range. It is claimed that the BC data is accurate (and repeatable) to +/- 1% for all bullets tested.

Detailed stability data is also included which can be used to determine suitable twist rates for bullets in various environments.

View Sample Page from Ballistic Performance of Rifle Bullets:
Bryan Litz Bullet Book Applied Ballistics BCs

NOTE: This is a reference book which contains mostly data pages. There is a single chapter in the beginning which talks about how to use the data. For a more thorough understanding of the science of external ballistics, readers are referred to: Applied Ballistics for Long Range Shooting (2d Edition).

Permalink Bullets, Brass, Ammo, New Product 11 Comments »