April 3rd, 2018

Don’t Kill the Chrono! Setting up Chronos to Avoid Stray Shots

chronograph placement, shooting chrony, chrono, advisory, tech tip

There is nothing more frustrating (or embarassing) than sending a live round into your expensive new chronograph. As the photo below demonstrates, with most types of chronographs (other than the barrel-hung Magnetospeed), you can fatally injure your expensive chrono if it is not positioned precisely.

When setting up a chrono, we always unload the rifle, remove the bolt and bore-sight to ensure that the path of the bullet is not too low. When bore-sighting visually, set up the rifle securely on the sandbags and look through the bore, breech to muzzle, lining up the barrel with your aim point on the target. Then (during an appropriate cease-fire), walk behind the chronograph. Looking straight back through the “V” formed by the sky-screens, you should be able to see light at the end of the barrel if the gun is positioned correctly. You can also use an in-chamber, laser bore-sighter to confirm the visual boresighting (see photo).

Laser boresighter chronograph

Adjust the height, angle and horizontal position of the chronograph so the bullet will pass through the middle of the “V” below the plastic diffusers, no less than 5″ above the light sensors. We put tape on the front sky-screen supports to make it easier to determine the right height over the light sensors.

Use a Test Backer to Confirm Your Bullet Trajectory
You can put tape on the support rods about 6″ up from the unit. This helps you judge the correct vertical height when setting up your rifle on the bags. Another trick is to hang a sheet of paper from the rear skyscreen and then use a laser boresighter to shine a dot on the paper (with the gun planted steady front and rear). This should give you a good idea (within an inch or so) of the bullet’s actual flight path through the “V” over the light sensors. Of course, when using a laser, never look directly at the laser! Instead shine the laser away from you and see where it appears on the paper.

chronograph set-up

Alignment of Chronograph Housing
Make sure the chrono housing is parallel to the path of the bullet. Don’t worry if the unit is not parallel to the ground surface. What you want is the bullet to pass over both front and rear sensors at the same height. Don’t try to set the chrono height in reference to the lens of your scope–as it sits 1″ to 2″ above your bore axis. To avoid muzzle blast interference, set your chronograph at least 10 feet from the end of the muzzle (or the distance recommended by the manufacturer).

chronograph laser sky screens

Rifles with Elevated Iron Sights
All too often rookie AR15 shooters forget that AR sights are positioned roughly 2.4″ above the bore axis (at the top of the front sight blade). If you set your bullet pass-through point using your AR’s front sight, the bullet will actually be traveling 2.4″ lower as it goes through the chrono. That’s why we recommend bore-sighting and setting the bullet travel point about 5-8″ above the base of the sky-screen support shafts. (Or the vertical distance the chronograph maker otherwise recommends). NOTE: You can make the same mistake on a scoped rifle if the scope is set on very tall rings, so the center of the cross-hairs is much higher than the bore axis line.

Laser boresighter chronograph

TARGET AIM POINT: When doing chrono work, we suggest you shoot at a single aiming point no more than 2″ in diameter (on your target paper). Use that aiming point when aligning your chrono with your rifle’s bore. If you use a 2″ bright orange dot, you should be able to see that through the bore at 100 yards. Using a single 2″ target reduces the chance of a screen hit as you shift points of aim. If you shoot at multiple target dots, place them in a vertical line, and bore sight on the lowest dot. Always set your chron height to set safe clearance for the LOWEST target dot, and then work upwards only.

Other Chronograph Tips from Forum Members:

When using a chronograph, I put a strip of masking tape across the far end of the skyscreens about two-thirds of the way up. This gives me a good aiming or bore-sighting reference that’s well away from the pricey bits. I learned that one the hard way. — GS Arizona

A very easy and simple tool to help you set up the chronograph is a simple piece of string! Set your gun (unloaded of course) on the rest and sight your target. Tie one end of the string to the rear scope ring or mount, then pull the string along the barrel to simulate the bullet path. With the string showing the bullet’s path, you can then easily set the chronograph’s placement left/right, and up/down. This will also let you set the chrono’s tilt angle and orientation so the sensors are correctly aligned with the bullet path. — Wayne Shaw

If shooting over a chrono from the prone position off a bipod or similar, beware of the muzzle sinking as recoil causes the front of the rifle to drop. I “killed” my first chronograph shooting off a gravel covered firing point where I’d not given enough clearance to start with and an inch or two drop in the muzzle caused a bullet to clip the housing. — Laurie Holland

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April 3rd, 2018

M14 and M1A — Battle Rifle and Civilian Version Reviewed

M14 rifle Springfield M1A camp perry Shooting Sports USA

“Descended from the M1 Garand, the M14 utilized multiple improvements that made it a far superior firearm for combat and a much better rifle for competition.” — Dick Jones, Shooting Sports USA.

In the April 2018 issue of Shooting Sports USA, you’ll find a good article on the civilian version of the M14, now sold commercially as the Springfield M1A. An evolution of the battle-proven M1 Garand, the M14 was designed to shoot the 7.62×51 (.308 Win) round instead of the larger .30-06 Springfield cartridge used in WWI, WWII and Korea. While the vast majority of today’s M1As are chambered for .308 Win/7.62×51, Springfield Armory also produces a 6.5 Creedmoor version.

Dick Jones reports that accurized M14/M1As could post remarkable scores: “The accuracy potential of the M14/M1A is unquestionable. During their reign as service rifles, they produced multiple perfect 200 scores at 600 and 1000 yards in the hands of top shooters. This is a difficult feat with a modern, scoped, magnum-caliber rifle and remarkable with an iron-sighted battle rifle. Good competition rifles can group 10 shots under one MOA, and the meticulously-massaged rifles used by the top shooters during my career would consistently put up 10 shots under an inch at 200 yards off a test cradle.”

M14 rifle Springfield M1A camp perry Shooting Sports USA


CLICK HERE to REGISTER for 2018 Springfield M1A Match »

For many years, the semi-auto version of the M14 was “top dog” in iron sights Service Rifle competition. Now that discipline is dominated by .223 Rem (5.56×45) AR-type rifles, but the bigger .308-caliber rifle, now sold as the M1A, remains popular. The CMP hosts a major M1A Match every year at Camp Perry, sponsored by Springfield Armory. Significant prizes are awarded. M1A Match competitors took home over $25,000 worth of cash and merchandise in 2016.

M14 rifle Springfield M1A camp perry Shooting Sports USA
Photo courtesy Civilian Marksmanship Program.

In this video, YouTube Reviewer Hickok 45 compares the M1 Garand and the M14/M1A:

See how the modern M1A is built in this Springfield Armory Video:

As racing improves automobiles, competition improves firearms, and the current crop of Springfield M1As, from the Basic to the top-of-the-line Super Match and Loaded models, reflects the years of development. The M14 and its variants are still in service today and it’s still considered by many to be the best battle rifle in the history of the U.S. Military. — Dick Jones, Shooting Sports USA

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April 3rd, 2018

Doom to Small Varmints — 2000 Rounds of 17 HMR for $339.00

Bulk 17 HMR ammo deal

For blastin’ small varmints (such as ground squirrels) out to 200 yards or so, it is hard to beat the little 17 HMR rimfire cartridge. Yes there are much more powerful centerfire varmint rounds, and the newer 17 WSM rimfire offers more velocity, but the 17 HMR offers a winning combination of accuracy and affordability, plus there are many excellent 17 HMR factory rifles with a variety of stock options. We like the Savage A17 with thumbhole stock. Volquartsen also makes fine 17 HMR rigs, including this rifle belonging to Top Shot Champion Dustin Ellermann. Dustin says this rig has shot half-MOA groups at 100 yards with CCI A17 ammunition.

Dustin Ellermann 17 HMR varmint Rifle

For Those Serious Varmint Safaris — 2000 Rounds of 17 HMR
Fans of the 17 HMR who shoot a lot of rounds during varmint season should rejoice at this latest offer from Midsouth Shooters Supply — 2000 rounds of Hornady 17 HMR V-Max for $339.00. That’s a very good deal that works out to $8.47 per 50-round box. This Hornady ammo typically sells for about $11-$12 per box ($11.69 at MidwayUSA), so you can see this is a very attractive offer. 2000 rounds may seem like a lot, but we’ve shot up to 400 rounds in a single afternoon on a West Coast Squirrel Safari.

Bulk 17 HMR ammo deal

Permalink Bullets, Brass, Ammo, Hunting/Varminting 1 Comment »