June 3rd, 2020

0.8 MOA for 500 Shots at 300 Meters — Sierra Test Tunnel Result

Sierra Bullets 500 round tunnel test

For load development, some guys shoot 3-shot groups. Other guys shoot 5-shot groups, or even 10-shot strings. But for testing its projectiles, Sierra Bullets takes it to another level entirely. A while back Sierra was testing its .30-Caliber 175gr HPBT MatchKing in the Sierra underground tunnel. The results appear above — a FIVE HUNDRED Round group!

500 Shots Form 0.82 MOA Group at 300m (328 yards)
The photo above shows the result of 500 shots taken in a 300 meter test tunnel. Sierra’s trigger-pullers sent five full boxes of bullets down-range at a single target. The raw group size, edge to edge of the farthest shots, is about 3.13 inches, as shown on the calipers’ metal linear scale. Subtract a .308″ nominal bullet diameter* to get the 2.823″ on the digital readout. So you’re seeing a 2.823″ group at 300 meters (328 yards). One MOA at this distance is 3.435″ so this 500-round group is 2.823 divided by 3.435 or 0.82 MOA (0.8218 MOA to be precise).

This 500-round group was shoot as part of a pressure/velocity test for a commercial customer. The cartridge was .308 Winchester, loaded at 2.800″. The powder was Reloder 15. A 26″ barrel was shot from a return to battery rest. The gun was cleaned every 125 rounds and two foulers shot.

What do you think — could you beat this group from a bench for 500 rounds?

One Facebook poster joked: “500-round group? Everyone knows anything less than 1000-round groups are a waste of time and statistically irrelevant.”

Test Tunnel Sierra

Sierra Bullets Test Tunnel Barrels

Sierra’s 300 Meter Testing Tunnel
Ever wonder how (and where) Sierra tests its bullets? The answer is underground, in a 300-meter test tunnel located under Sierra’s factory in Sedalia, Missouri. The photo above shows the construction of the tunnel back in May, 1990. Like most bullet manufacturers, Sierra does live-fire bullet testing of its projectiles. Sierra’s 300-meter test range is the longest, manufacturer-owned underground bullet test facility in the world. Sierra offers free tours of the test tunnel as part of Sierra’s Factory Tour Program.

* Normally, to get an exact group size, you should subtract the TRUE bullet hole size, which is usually smaller than the nominal bullet diameter. E.g. a .308 bullet hole may show on paper as .298 or so. But here, for simplicity, we are subtracting .308″ because we do not have the original target to measure.

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June 3rd, 2020

Shooting Skills — Canting Left or Right Alters Point of Impact

rifle level canting shooting rifle Ryan Cleckner

In a helpful NSSF video, Ryan Cleckner explains why you normally should avoid canting your rifle — rotating it clockwise or counter-clockwise. Cleckner explains that canting the rifle in one direction or another will change the point of impact: “When you rotate the rifle, not only does the [POI move] in the direction that you’re rotated, [but] it also loses some of its elevation as it rolls down.” This, Cleckner explains, can make you miss on one side or the other:

Cant to the Left — You’re going to miss low and left.
Cant to the Right — You’re going to miss low and right.

rifle level canting shooting rifle Ryan Cleckner

In this video, starting at the one-minute mark, Cleckner shows the effect of rifle canting when engaging a 600-yard target. A few degrees of cant (either to the left or to the right), moves the shot POI completely off the steel silhouette target. The POI change occurs mainly because you are lowering (and laterally shifting) the scope sight-line relative to the bore axis, effectively changing your zero.

David Tubb has explained: “Every 1 degree you are off on a cant, is about six inches of difference laterally at 1000 yards”.

Position Shooting with Sling — Rifle Cant Considerations
Cleckner’s discussion assumes that the scope or sights are set to hit center with the rifle level and plumb. That works for most situations when shooting prone off bipod, front mechanical rest, or front sandbag. However, many sling shooters, including David Tubb and John Whidden, do tilt or cant their rifles slightly inward because this allows a more comfortable hold with sling, or allows better eye-to-sight alignment. Holding the rifle at an angle can work — but the angle of cant must be consistent for every shot. Canting the rifle is not a sin by itself. However, after you confirm your zero on your target, the degree of cant must be the same for EVERY shot. You must maintain that exact same degree of rotation on each shot or you will experience the shot POI movement Cleckner illustrates. Consistency is the key.

John Whidden
John Whidden, 5-time Nat’l Long Range Champion, holds a Palma rifle. John now shoots a match rifle with an Anschutz stock which he holds more upright, but still with some counter-clockwise cant. John also installed his iron sights at an angle so that the adjustments are correct (and plumb) even with his canted hold: “While it may not be obvious in the picture, the sights on my rifle are set up so that they’re straight vertical and horizontal while I hold the rifle canted. Making sure your adjustments (scope or sights) are vertical and horizontal is a critical piece of the pie.”

Inexpensive Dual-Diameter Scope-Mounted Bubble Level
The best way to avoid inconsistent rifle canting is to use a bubble level fitted to rail or scope. One very affordable and versatile product is the Jialitte Scope Bubble Level. This features a 30mm milled inside diameter, plus an inner insert ring so it will also fit 1″-diameter main tubes. The Jiaalitte unit is nicely radiused, and has a low profile in the middle. User reviews have been very positive. You could easily pay $35.00 or more for a 30mm scope level. This costs just $10.99.

Scope Optic bubble level 30mm 1

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June 3rd, 2020

Millions of New Gun Owners in America

NSSF Survey new gun owners covid-19 pandemic riots

C0VID-19 lock-downs and now riots and looting in America have caused Americans to be very concerned with the safety of their families and security of their property. Not surprisingly, gun sales have skyrocketed in 2020 compared to the year before. Notably, a significant percentage — 40.2% — of the firearms purchasers are FIRST-TIME gun buyers. And retail dealers say about 40% of those first-time buyers are females, a historically high number. Overall it is estimated that 2.5 MILLION Americans joined the ranks of gun owners during the first four months of 2020.

NSSF-adjusted NICS figures showing year-over-year increases of 80 percent in March and 69 percent in April 2020. These strong increases led to more than 6.5 million NSSF-adjusted background checks in the first four months of 2020, up 48% from 4.4 million during the same period in 2019.

NSSF May 2020 Survey of Firearm Retailers
In May 2020, NSSF surveyed firearm retailers to learn more about gun sales during the first four months of 2020. Retailers reported an increased number of first-time gun buyers, estimating that 40.2% of their sales were to this group. This is a huge increase — nearly double — over the 24% annual average of first-time gun buyers that retailers have reported in the past. Semiautomatic handguns were the primary firearm being purchased by first-time buyers, outpacing the second-most purchased firearm, shotguns, by a 2-to-1 margin. Modern sporting rifles, revolvers and traditional rifles rounded out the top five types of firearms purchased by first-time gun buyers.

All this equates to more than 2.5 million new gun owners in 4 months of 2020.

Retailers noted that these new customers were spending $595 on an average sale and that 40.1% of first-time gun buyers in the first four months of 2020 were female. The main purchase driver among the group was personal protection, followed by target shooting and hunting. Also of note was that 25% of first-time buyers had already taken some form of firearms safety course.

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