July 6th, 2018

2018 King of 2 Miles (KO2M) Highlights Report

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The 2018 King of 2 Miles (KO2M) event took place July 2-4 in Raton, New Mexico. Conditions were very challenging this year, yet three shooters managed to hit the most distant 3,525-yard plate at least once in five shots, a remarkable accomplishment. At that range the bullet was in flight about six seconds.

Robert Brantley of Team Manners Composite Stocks is the new King of 2 Miles. Congrats to Robert and his team-mates. Robert amassed 85178 points, finishing over 20,000 points ahead of runner-up John Buhay. Paul Phillips of Team Applied Ballistics finished third. FULL K02M 2018 RESULTS HERE.

King 2 miles 2018 raton new mexico

King 2 miles 2018 raton new mexico
Here’s Robert Brantley after his superb qualifying performance, which set a new 2018 King of 2 Miles qualifying round record. Going perfect on targets 1, 2, and 3, Robert missed just one shot on Target 4 of the qualifying phase, amassing 51355 points, a new K02M record.

King 2 miles 2018 raton new mexico

CLICK HERE for a very complete and thorough KO2M report created by The Precision Rifle Blog (PRB). This excellent PRB Report contains complete load and rig specifications for the top five shooters. In addition, the PRB Report includes a full run-down on this year’s event.

K02m 2018 Raton New mexico Cheytac barrett
Though the trigger pullers get the glory, this is really a three-man game. One guy shoots, a second team member spots for hits and calls corrections, and a third watches mirage and makes wind calls.

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Multi-Day, Multi-Distance Competition with Farthest Target at 3525 Yards
The K02M Competition runs in stages, with the distances getting farther with each round. After five shots on target 1 at 1547 yards, there are then three shots per target for the remaining three parts of the Qualifying round. Then, in the three-target Finals phase, there are with five shots per target. You get more points for earlier hits in each string, and there are no sighters during the match. The event started with a tough Cold Bore Challenge — a single-shot at 1689 yards, just shy of one mile. Only three out of 62 competitors made that cold-bore mile shot on a 16″ plate, about 1 MOA at that distance. After that there are two rounds with the targets arrayed as follows.

KO2M Qualification Round
1,547 yards: 5 shots, 24” x 37” rectangle
1,719 yards: 3 shots, 24” x 37” rectangle
1,890 yards: 3 shots, 30” x 37” rectangle
2,095 yards: 3 shots, 30” x 37” rectangle
KO2M Finals Round — July 4
2,727 yards: 5 shots, 33” x 41” rectangle
3,166 yards: 5 shots, 42” x 54” rectangle
3,525 yards: 5 shots, 48” x 60” rectangle

Big Bore Rifles with High-BC Bullets
This year saw the continued evolution of equipment. Top shooter Brantley shot a .416 Barrett with 500gr Cutting Edge bullets. Robert’s massive 44-lb rifle featured a 39″ K&P barrel, McMillan action, and a Manners LRT (Long Range Tactical) stock designed expressly for this KO2M competition.

Second Place John Buhay shot an improved version of the .375 CheyTac, with 353gr Lehigh Defense Match Solid bullets. Buhay’s 37.6-lb rig bosted a BAT action and 36″ Krieger barrel along with a fairly conventional McMillan MBR 1K benchrest stock. Mark King built the rifle.

Third Place Paul Phillips campaigned a .416 Barrett with 550gr Cutting Edge Lazer bullets. Paul’s 42-lb rig featured a BAT action and McMillan Beast 1 stock. Shown below is the latest rifle of 2017 K02M champ Derek Rodgers, a .416 Barrett also in a McMillan Beast. Derek spotted for Phillips in the match.

derek rodgers ko2m beast

Optics Options
There was quite a variety of scopes used by Top K02M competitors, evidence that a number of manufacturers now offer optics with abundant elevation and the ability to stand up to heavy recoil. Here are the optics choices for the Top Five Shooters:

1. Bushnell XRS II 4.5-30x50mm with G3 reticle in Badger UniMount
2. Nightforce ATACR 5-25x56mm with MOAR reticle, with ERA-TAC Inclined Mount
3. Nightforce ATACR 5-25×56mm, with Charlie TARAC external Prism System for Elevation
4. Leupold Mark 5HD 5-25×56mm, in Spuhr mount with Charlie TARAC
5. Burris XTR II 5-25x50mm in Barrett rings

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Notably, two of the top five used the Charlie TARAC prism system. This provides a ton of extra elevation by essentially shifting the view seen through the scope. The unit fits to the scope’s front objective.

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July 6th, 2018

TECH Tip: Safe Loading Practices for Different Bullet Shapes

USAMU Reloading Bullet Safety

This article, from the USAMU Facebook Page, concerns reloading safety. In the relentless quest for more speed and flatter ballistics, some hand-loaders load way too hot, running charges that exceed safe pressure levels. Hint: If you need a mallet to open your bolt, chances are your load is too hot. Stay within safe margins — your equipment will last longer, and you won’t risk an injury caused by over-pressure. In this article, the USAMU explains that you need to account for bullet shape, diameter, and bearing surface when working up a load. Don’t assume that a load which is safe for one bullet will be safe for another even if both bullets are exactly the same weight.

USAMU Reloading tips Army Marksmanship

Today, we continue our handloading safety theme, focusing on not inadvertently exceeding the boundaries of known, safe data.

Bullet manufacturers’ loading manuals often display three, four, or more similar-weight bullets grouped together with one set of load recipes. The manufacturer has tested these bullets and developed safe data for that group. However, seeing data in this format can tempt loaders — especially new ones — to think that ALL bullets of a given weight and caliber can interchangeably use the same load data. Actually, not so much.

The researchers ensure their data is safe with the bullet yielding the highest pressure. Thus, all others in that group should produce equal or less pressure, and they are safe using this data.

However, bullet designs include many variables such as different bearing surface lengths, hardness, and even slight variations in diameter. In fact, diameters can occasionally range up to 0.001″ by design. Thus, choosing untested bullets of the same weight and caliber, and using them with data not developed for them can yield excess pressures.

This is only one of the countless reasons not to begin at or very near the highest pressure loads during load development. Always begin at the starting load and look for pressure signs as one increases powder charges.

Bullet Bearing Surface and Pressure
Bullet bearing surface length (BSL) is often overlooked when considering maximum safe powder charges and pressures. In Photo 1, note the differences in the bullets’ appearance. All three are 7 mm, and their maximum weight difference is just five grains. Yet, the traditional round nose, flat base design on the left appears to have much more BSL than the sleeker match bullets. All things being equal, based on appearance, the RN/FB bullet seems likely to reach maximum pressure with significantly less powder than the other two designs.

Photo 1: Three Near-Equal-Weight 7mm Bullets with Different Shapes
USAMU Bullet Ogive Comparison Safety Reloading

Due to time constraints, the writer used an approximate, direct measurement approach to assess the bullets’ different BSLs. While fairly repeatable, the results were far from ballistics engineer-grade. Still, they are adequate for this example.

Bullet 1 (L-R), the RN/FB, has a very slight taper and only reaches its full diameter (0.284 inch) very near the cannelure. This taper is often seen on similar bullets; it helps reduce pressures with good accuracy. The calculated BSL of Bullet 1 was ~0.324″. The BSL of Bullet 2, in the center, was ~0.430″, and Bullet 3’s was ~ 0.463″. Obviously, bullets can be visually deceiving as to BSL!

Some might be tempted to use a bullet ogive comparator (or two) to measure bullets’ true BSL for comparison’s sake. Unfortunately, comparators don’t typically measure maximum bullet diameter and this approach can be deluding.

Photo 2: The Perils of Measuring Bearing Surface Length with Comparators
USAMU Bullet Ogive Comparision Safety Reloading

In Photo 2, two 7mm comparators have been installed on a dial caliper in an attempt to measure BSL. Using this approach, the BSLs differed sharply from the original [measurements]. The comparator-measured Bullet 1 BSL was 0.694” vs. 0.324” (original), Bullet 2 was 0.601” (comparator) vs. 0.430” (original), and Bullet 3 (shown in Photo 2) was 0.602” (comparator) vs. 0.463” (original). [Editor’s comment — Note the very large difference for Bullet 1, masking the fact that the true full diameter on this bullet starts very far back. You can use comparators on calipers, but be aware that this method may give you deceptive reading — we’ve seen variances just by reversing the comparators on the calipers, because the comparators, typically, are not perfectly round, nor are they machined to precision tolerances.]

Thanks to the U.S. Army Marksmanship Unit for allowing the reprint of this article.

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