July 2nd, 2019

Tuner TECH — POI Shift with Barrel Tuner Position Changes

Tuner Pascal Bukys Point of Impact shift test 6 PPC benchrest

6PPC Pascal Fischbach Bukys Barrel Tuner sine waveHave a good look at the photos below — this may be one of the most noteworthy target strings we’ve ever published. What you can see is the effect of barrel tuner position on point of impact (POI). You can clearly see that the tuner position alters the up/down POI location in a predictable fashion.

This remarkable 15-shot sequence was shot by French benchrester Pascal Fischbach using his 6 PPC fitted with a CG (Carlito Gonzales) action and a Bukys barrel tuner.

Pascal reports: “After [bullet] seating and load validation, I put the Bukys tuner on, screwing it out 10 turns. According to Carlito, the CG’s super stiff action-to-barrel fit gives a faster vibration modulus that is detrimental below 10 turns [position of the tuner].” Pascal’s procedure was to screw out the tuner 1/4 turn progressively from one shot to the next. He shot one bullet at each tuner position, with a total of 15 shots.

15-Shot Sequence with Tuner Changes
6PPC Pascal Fischbach Bukys Barrel Tuner sine wave
CLICK HERE to SEE Large Version of Complete Test Strip (All 15 shots in a row).

Left Half of Target Strip (shots with 1/4 rotation change of tuner in sequence)
6PPC Pascal Fischbach Bukys Barrel Tuner sine wave

Right Half of Target Strip (shots with 1/4 rotation change of tuner in sequence)
6PPC Pascal Fischbach Bukys Barrel Tuner sine wave

Pascal observed: “Note the point of impact displacement [from shot to shot] tracks clearly along a sinusoide (sine wave curve).” This is indeed notable and significant! This shows how the tuner’s ability to change barrel harmonics can alter the position of the muzzle as each bullet exits, resulting in a higher or lower POI. Pascal sent his results to Carlito Gonzales in Argentina for analysis.

Pascal poses this question to readers: “Guess which three positions Carlito recommends to try?”

Editor’s Note: While this target sequence clearly shows how tuner position can alter bullet point of impact, this, by itself, does not tell us which tuner position(s) are best for accuracy. That will require further multi-shot group testing, involving careful experimentation with tuner position (and powder charge weights). But for those folks who doubt that a tuner can make a difference on a short, fat barrel, just take another look at the photos. The up/down changes are undeniable, and noteworthy in the wave pattern they follow.

Shooting Set-up and Test Conditions:
Pascal did this test at an outdoor range under very good conditions: “This was shot at my home range, outdoors, with four Smiley flags. The range is a narrow cut in high woods. Wind was consistent with readable flags. I started testing the tuner from 10 turns out and on to 15. I recently… found a sweet spot very close to the rearmost position of the tuner, so the rigidity provided by this super long tenon (just short of 70mm) was not a reason to overlook the recommended Bukys tuning procedure.”

6PPC Pascal Fischbach Bukys Barrel Tuner sine wave

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August 29th, 2018

Legends of Accuracy — The Secrets of the Houston Warehouse

From the late ’70s through 1983, a huge, concrete-walled warehouse in Houston was used for benchrest testing. Virgil King and Bob Fisher set up a bullet-catching backstop at the end of a 30-yard-wide, 325-yard-long fire lane that remained unobstructed even when the warehouse was in use. This allowed accuracy tests in virtually perfect “no wind” conditions. Over a six-year period, about 30 shooters were invited to test their rifles. The results were amazing, with numerous “zero groups” being shot in the facility. Many of the lessons learned in the legendary Houston Warehouse still help benchresters achieve better accuracy today.

Dave Scott wrote a superb article, the Secrets of the Houston Warehouse which appeared in a special issue of Precision Shooting Magazine. That issue has long been sold out, but, thankfully, Secrets of the Houston Warehouse is now on the web: CLICK HERE to READ Secrets of the Houston Warehouse.

Houston WarehouseDave Scott explains why the Warehouse was so unique:

“Over a period of six years, the levels of accuracy achieved in the Houston Warehouse went beyond what many precision shooters thought possible for lightweight rifles shot from sandbags and aimed shot-to-shot by human eye. For the first time, a handful of gifted, serious experimenters — armed with the very best performing rifles (with notable exceptions) — could boldly venture into the final frontiers of rifle accuracy, a journey made possible by eliminating the baffling uncertainties of conditions arising from wind and mirage. Under these steel skies, a shooter could, without question, confirm the absolute limits of accuracy of his rifle, or isolate the source of a problem. In the flawlessly stable containment of the Houston Warehouse … a very few exceptional rifles would display the real stuff, drilling repeated groups measuring well below the unbelievably tiny .100″ barrier. The bulk of rifles, however, embarrassed their owners.”

Scott’s article also reveals some interesting technical points: “One thing that IS important is that the bullet be precisely seated against the lands. T.J. Jackson reported this fact in the May 1987 issue of Precision Shooting. In a letter to the Editor, T.J. wrote, ‘…in all our testing in that Houston warehouse… and the dozens and dozens of groups that Virgil King shot in there ‘in the zeroes’… he NEVER fired a single official screamer group when he was ‘jumping’ bullets. All his best groups were always seated into the lands, or at the very least… touching the lands. Virgil said his practice was to seat the bullets so the engraving was half as long as the width of the lands. He noticed an interesting phenomenon with rifles that could really shoot: if the bullets were seated a little short and the powder charge was a bit on the light side, the groups formed vertically. As he seated the bullets farther out and increased the powder charge, the groups finally became horizontal. If he went still farther, the groups formed big globs. He said the trick is to find the midway point between vertical and horizontal. That point should be a small hole.”

You should definitely read the complete article, as it provides many more fascinating insights, including shooting technique, barrel cleaning, neck-turning, and case prep.

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October 9th, 2012

Secrets of the Houston Warehouse — Read this classic article

From the late ’70s through 1983, a huge, concrete-walled warehouse in Houston was used for benchrest testing. Virgil King and Bob Fisher set up a bullet-catching backstop at the end of a 30-yard-wide, 325-yard-long fire lane that remained unobstructed even when the warehouse was in use. This allowed accuracy tests in virtually perfect “no wind” conditions. Over a six-year period, about 30 shooters were invited to test their rifles. The results were amazing, with numerous “zero groups” being shot in the facility. Many of the lessons learned in the legendary Houston Warehouse still help benchresters achieve better accuracy today.

Dave Scott wrote a superb article, the Secrets of the Houston Warehouse which appeared in a special issue of Precision Shooting Magazine. That issue has long been sold out, but, thankfully, Secrets of the Houston Warehouse is now on the web: CLICK HERE to READ Secrets of the Houston Warehouse.

Houston WarehouseDave Scott explains why the Warehouse was so unique:

“Over a period of six years, the levels of accuracy achieved in the Houston Warehouse went beyond what many precision shooters thought possible for lightweight rifles shot from sandbags and aimed shot-to-shot by human eye. For the first time, a handful of gifted, serious experimenters — armed with the very best performing rifles (with notable exceptions) — could boldly venture into the final frontiers of rifle accuracy, a journey made possible by eliminating the baffling uncertainties of conditions arising from wind and mirage. Under these steel skies, a shooter could, without question, confirm the absolute limits of accuracy of his rifle, or isolate the source of a problem. In the flawlessly stable containment of the Houston Warehouse … a very few exceptional rifles would display the real stuff, drilling repeated groups measuring well below the unbelievably tiny .100″ barrier. The bulk of rifles, however, embarrassed their owners.”

Scott’s article also reveals some interesting technical points: “One thing that IS important is that the bullet be precisely seated against the lands. T.J. Jackson reported this fact in the May 1987 issue of Precision Shooting. In a letter to the Editor, T.J. wrote, ‘…in all our testing in that Houston warehouse… and the dozens and dozens of groups that Virgil King shot in there ‘in the zeroes’… he NEVER fired a single official screamer group when he was ‘jumping’ bullets. All his best groups were always seated into the lands, or at the very least… touching the lands. Virgil said his practice was to seat the bullets so the engraving was half as long as the width of the lands. He noticed an interesting phenomenon with rifles that could really shoot: if the bullets were seated a little short and the powder charge was a bit on the light side, the groups formed vertically. As he seated the bullets farther out and increased the powder charge, the groups finally became horizontal. If he went still farther, the groups formed big globs. He said the trick is to find the midway point between vertical and horizontal. That point should be a small hole.”

You should definitely read the complete article, as it provides many more fascinating insights, including shooting technique, barrel cleaning, neck-turning, and case prep.

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September 16th, 2012

Great Deals on the Best Gun Books — Picked by Our Editors

AccurateShooter Amazon.comBelieve it or not, 90% of non-academic printed books are sold in the last quarter of the year. If you are considering purchasing books for your own gun library or as gifts for family members or friends, we’ve just made your life easier. Over the past few years, we’ve compiled a list of the best-written and most informative books for rifle shooters and precision hand-loaders.

CLICK HERE to visit our Shooters’ Bookstore.

You could spend days compiling your own list and then tracking down all these different titles. Or, with one click, you can find it all in one place in our new AccurateShooter virtual bookstore. We’ve teamed up with Amazon.com to provide the top titles at very competitive prices. All order-taking, payment processing, and shipping is handled by Amazon. We’ve just saved you the effort of finding the best titles.

Shown below are some of the most popular titles we carry. Use the arrows (lower right) to shuffle books from back to front. Click on a book jacket to get more info or start shopping. You’ll find dozens more quality gun-related titles in our Shooters’ Bookstore.

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January 20th, 2010

SHOT Show Report: Murdica Tests New Norma 6PPC Brass

Lou MurdicaAt the request of AccurateShooter.com, respected Benchrest ace Lou Murdica tested the brand new, early production Norma 6PPC brass. Lou shot 30 cases (both turned and unturned) over the past few days, and he endorses the Norma brass without hesitation. Lou says “the Norma PPC brass is great brass. Without a doubt this will be highly competitive brass in the short-range benchrest group”. Lou did observe that the necks on the Norma brass were slightly thinner than on Lapua 220 Russian brass, but that really doesn’t matter. With a slight neck turn, Lou declares, “the Norma PPC brass is as good as any out there.”

Lou said, based on his testing, the Norma brass holds pressure well, and the accuracy is outstanding. Lou shot five 5-round groups, as in a match course of fire, and his largest group was “around 0.148″ at 100 yards.

If you’re a short-range benchrester, definitely watch this video and listen to Lou. He thinks this new Norma brass will “change the game”. Note — Lou said most PPC shooters can shoot the Norma cases with no change in their powder recipes. So you won’t lose any velocity using Norma’s new brass. Lou was very impressed with Norma’s new offering, enough so that he declared: “I would go right for the Norma right now if I could put a bunch in my hand.”

YouTube Preview Image
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July 22nd, 2008

Bob Bock Sets New F-Class Record: 449-32X

Bob Boch, current captain of the U.S. F-Class Open Rifle Team, has posted a new multi-distance F-Class record, a fantastic 449-32x. The new record was shot at the Forbes Rifle & Pistol Club in New York state. This was the “long-range” Palma-style match with targets at 800, 900, and 1000 yards. The Palma course of fire is 15 shots at 800 yards, 15 shots at 900 yards, and 15 shots at 1000 yards. Unlimited sighters precede the 800-yard stage, there are two sighters for 900, and two sighters for 1000.

F-Class Open Rifle Bock

Bob was shooting a 6.5-284 with a 30″ Bartlein barrel, 5R rifling, 1:8.5″ twist, 1.250″ straight contour. Barrel fitting and metal work was done by Warner Tool Co. in Keene, NH. Bob says: “My 6.5-284 load consist of the best bullet ever made, the 140 grain Berger VLD, behind 48.4 to 49.0 grains of H4350, depending on the particular barrel I am shooting. I have been shooting Norma brass in the past six months.

Setting the Record — Just one “9”, On the Very Last Shot
Bob reports: “The conditions were good in my opinion, but conditions are like beauty, it is in the eye of the beholder. It was hot and humid, over 90 degrees by the time we got to the 1000 yard, with probably 90% humidity. Lots of grumbling on the line. The wind was light, but the flags are in the trees on the Forbes range. Very little if any use. It was overcast at 800, sun breaking in/out at 900 and very sunny by the 1000. Mirage varied between boiling, running and disappearing. The 9 was my 45th shot. The rifle/ammo performed superbly, the 9 was operator error for sure. Last-shot-itis or missing the change, you take your pick.”

Congratulations to Bob for setting an impressive new mark for the F-Class open division. A retired mechanical engineer, Bob was born in Hungary and moved to the United States in 1964. He has been involved in all kinds of shooting including pistol silhouettes, IPSIC and combat sniper rifle in various parts of the country. He has been shooting F-Class since 2001. Bob won the 2007 U.S. F-Class Open National Championship in Raton. He was a member of the 2005 U.S. F-Class Team and placed 7th in the individual World Championship, plus was a member of the 4-man team that won the Rutland Cup at the World Championship in South Africa. Bob also won the McDonald Stewart Grand Aggregate in the F-Class final of the 2007 Canadian Fullbore Championship.

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