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.”
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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The folks at Sierra Bullets asked a few staff bulletsmiths a classic question about guns: “If you could own only one firearm which one would you choose?” There were many interesting answers including a “cheater” response — the drilling — which is really two guns in one. The most-often mentioned chambering was the venerable .30-06. Respondents cited its versatility, hunting prowess, and ready availability of ammo. The popular .308 Winchester, as expected, got mentions as did its cousins the .243 Win and 7mm-08. There were quite a few votes for classic lever guns, as well as 12-gauge shotguns. Two bulletsmiths cited the .22 LR, and we can certainly see the logic in that answer. The little rimfire cartridge is versatile, quiet, and inexpensive.
We ask our readers the same question — if you could only have one long gun, what type of firearm would it be? List the gun type and chambering in the comments section.
If You Could Have Just One Long-Gun — ANSWERS:
Media Relations Manager Carroll Pilant answered: “I would NEVER own only one gun. If I HAD to pick one, it would be a drilling in 12 gauge over .30-06.”
Ballistic Technician Rich Machholz answered: “The early tang safety Ruger M77s pretty much have all you could want in a bolt gun, but I do like the Winchester lever guns and the combination guns, particularly the drillings. Since I have the first two, I’m going for a Doug Turnbull 1886 or a side by side 20 gauge over .223 drilling.”
Ballistic Technician Philip Mahin answered: “More than likely it would have to be a bolt action .30-06. The reliability is legendary on a wide range of game animals and factory ammunition has still been available at my local stores even in these tough times.”
Ballistic Technician Duane Siercks answered: “If I had to boil it all down to one gun, it would probably be a .30-06. I have a Remington 700C (custom shop gun) that has worked very well for anything and everything I have ever wanted to do with it.”
Ballistic Technician Paul Box answered: “A .22 Rimfire.”
Chief Ballistician Tommy Todd answered: “Remington 700 in .308 Winchester.”
VP – Sales & Marketing Matt Reams answered: “A light weight Kimber in 25-06.”
Production Toolsetter Brad Vansell answered: “Savage weather warrior 7mm-08 is my rifle of choice.”
Production Toolsetter Dan Mahnken answered: “The .308 Winchester rifle — [based on the] wide range of bullets made and the wide range of things that one can hunt with it.”
Process Engineer David Palm answered: “Savage action 243 Winchester.”
Ballistic Technician Gary Prisendorf answered: “Probably a .22 LR. It may not be the best choice, but you could use it for about anything if you really had to.”
Production Manager Chris Hatfield answered: “Beretta A300 Outlander 12 gauge.”
As folks are stuck at home with the Pandemic lock-downs, many guys are thinking about projects involving their AR-15s sitting in their safes. We’ve seen some threads in our Forum asking about the .224 Valkyrie, an AR-centric cartridge that offers significantly better long-range performance than the .223 Remington (5.56×45). If you own a .224 Valkyrie, or are thinking about adding a .224 Valkyrie upper to your MSR (Modern Sporting Rifle) arsensal, here is load information from industry leaders Hodgdon and Sierra.
With the 90gr SMK (or similar High-BC projectiles), the .224 Valkyrie offers ballistics similar to the 6.5 Creedmoor but with significantly less felt recoil.
Hodgdon has reloading data for the .224 Valkyrie, a popular new cartridge optimized for the AR15 platform. “At Hodgdon, we’ve been researching this cartridge since before its introduction and are excited to release load data for the Valkyrie featuring powders like Hodgdon CFE 223, IMR 8208 XBR, and Hodgdon Varget” reports Ron Reiber, Hodgdon product manager/ballistician. Access the .224 Valkyrie Data via Hodgdon’s Reloading Data Center.
While new load data will continue to be updated, there is currently data for 80 different loads with bullet weights ranging from 50 to 90 grains. NOTE: The load data covers Hodgdon, IMR, and Winchester brand powders only. See Sierra Data for other powder brands. Bullet brands included are: Federal, Hornady, Nosler, Sierra and Swift.
About the .224 Valkyrie Cartridge
Basically a 6.8 SPC necked down to .22, the Valkyrie has a shorter case than the .223 Remington (and 5.56×45 NATO). This allows you to load the longest, heaviest .224-caliber bullets and still feed reliably from an AR15-type magazine. Designed to rival the .22 Nosler while still running well in ARs, the .224 Valkyrie offers excellent long-range performance when loaded with modern, high-BC bullets. We expect some bolt-action PRS shooters might adopt the .224 Valkyrie. Why? Reduced recoil. With the 90gr SMK, the .224 Valkyrie offers ballistics similar to the 6.5 Creedmoor but with significantly less felt recoil.
The new .224 Valkyrie has already developed a loyal following: “Shooting heavier bullets in an AR-platform rifle that maintain supersonic speeds beyond 1,300 yards has captured the interest of shooters and handloaders everywhere” — Hodgdon Powders
Our friend Gavin Gear of Ultimate Reloader.com found a superbly accurate load with Berger 80.5gr bullets.
IMPORTANT: Check Out Sierra’s .224 Valkyrie DATA
Sierra Bullets has also published extensive load data for the .224 Valkyrie. This covers over a dozen powder types — many more than the Hodgdon database. Sierra’s .224 Valkyrie load data covers projectiles from 50 grain all the way up to 95 grains. With the 90 to 95 grain bullets, the little Valkyrie can give 6mm match cartridges a real run for their money — offering similar ballistics with less recoil. When selecting a barrel for the long .224-cal bullets, specify a fast enough twist rate: “Sierra recommends a 1:6.5″-twist barrel for the #9290 22 cal 90 gr HPBT bullet. However, for cartridges like the Valkyrie, that can push them over 2650 fps muzzle velocity, a 1:7″-twist barrel will stabilize the bullet correctly.”
There are tens of thousands of products on display at SHOT Show, the world’s largest firearms industry trade show. On Day Two of the event, we visited many manufacturers to see their featured items, and new products for 2020. The vendors included McMillan Fiberglass Stocks, Forster Products, ELEY, G.A. Precision, Tikka/Sako, Gunwerks, Sierra Bullets, and more. Here are some interesting products as well as some eye-catching product displays.
Ballistic-X App Guru at SHOT Show
At the McMillan Fiberglass Stocks booth we met Jonathan Roberts, the talented computer wiz who created Ballistic-X software. This iOS/Android smartphone App quickly and easily calculates group sizes. Take a photo of your target, set some values (such as bullet diameter and distance to target), then use the touchscreen to place circles around each hole. The App will calculate group size (in MOA or Mils), distance to point of aim, and provide all the info in an overlay. Then click “save” to record your group for posterity!
Bright Red Record-Setting Rimfire Rifle
At the ELEY booth, we saw a stunning red rimfire rifle that belonged to our friend Dan Killough of Killough Shooting Sports. Dan used this rimfire benchrest rifle to win many matches and set a range record or two over the years. That is Dan in the upper left in the photo below.
David Tubb’s 33XC and 37XC — Big Cartridges for Big Guns
David Tubb, 11-time NRA Nat’l High Power Champion and 6-time NRA Nat’l Long Range Champion, had his ELR rifle on display. Using this rifle, David won the 2019 NRA ELR Heavy Gun Championship. David was at SHOT promoting some long-range cartridges — the 33XC and 37XC. In the video below, David Tubb, shooting his 33XC Tubb rifle, makes three consecutive hits at 2200 yards on a 36″x36″ steel plate at Valdina Ranch on 12/2/2018. In March 2019, the Fifty Caliber Shooters Association (FCSA) recognized this as an ELR (Extreme Long Range) World Record.
.22 LR Ammo for Extreme Long Range (ELR)
ELR Rimfire? That may seem like an oxymoron, but actually there are guys now shooting the little .22 LR cartridge at 300 yards and well beyond. You have to cope with some serious drop and drift at that distance, which makes this a good challenge, and great training for centerfire shooting at true Extreme Long Range. Cutting Edge Bullets will be producing .22 LR ammo with higher-BC projectiles optimized for the .22 LR rimfire long-range shooting disciplines.
Very Versatile Tikka T3x UPR
At the Beretta/Sako/Tikka booth, we liked the Tikka T3x UPR Stainless in 6.5 Creedmoor ($1500 MSRP). We liked the stock very much, and thought this was a very versatile gun that could be used for target shooting off bipod, hunting, even PRS, given its detachable magazine. The stock is very ergonomic and feels good. Tikka states the UPR’s stock “features an extra layer of carbon fiber mixed with fiberglass for increased rigidity and accuracy. The stock is coated with a rough surface for the best grip in any condition… choose between single stage or set trigger.”
Stunning Engraved Pistols from Baron Engraving
We stopped in our tracks at the Baron Engraving booth. There, in a glass showcase we saw an amazing selection of engraved pistols — 1911s and Browning High Powers. It’s great to see that the Art of Engraving is still alive and well. Baron engraving also does great work on revolvers and long guns.
Day Two Parting SHOT Photo
TV and film legends Chuck Norris and Lou (“The Incredible Hulk”) Ferrigno teamed up at SHOT Show. Norris drew a huge crowd of fans at the Glock booth.
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Sierra Bullets has released very complete load data for the popular 6.5 Creedmoor cartridge. This medium-sized cartridge has become one of the most popular chamberings for tactical and PRS shooters. The 6.5 Creedmoor combines excellent accuracy, good mag-feeding, good barrel life, moderate recoil, and reasonable component cost. That’s why this cartridge has caught on quickly.
Developed in 2007 by Dennis DeMille and Dave Emary, the 6.5 Creedmoor is a shortened and improved 30 TC cartridge case that was inspired by the .308 Winchester design. This short action design was created to maximize case capacity and a wide range of loading lengths, while still fitting in standard short action magazines. With the correct twist barrel, the versatile 6.5 Creedmoor can take advantage of the wide range of bullet weights available in 6.5 mm (i.e. .264 caliber). Reloaders should keep in mind that the 6.5 Creedmoor works best with medium to medium-slow powders such as H4350, Varget, Win 760, and RE-17. The light recoil and adaptability of the efficient 6.5 Creedmoor cartridge has already proven itself in high power, precision rifle series and benchrest competitions. Couple that with respectable barrel life and its intrinsic accuracy potential and you have a recipe for success which should insure its legacy for decades to come.
Here are three tables from the Sierra Bullets Reloading Manual (5th Edition). IMPORTANT — This is just a sample!! Sierra has load data for many other 6.5mm bullet types, including FB, Spitzer, SBT, HPBT, and Tipped MK from 85 grains to 142 grains. To view ALL 6.5 Creedmoor DATA, CLICK HERE.
INDICATES MAXIMUM LOAD – USE CAUTION
LOADS LESS THAN MINIMUM CHARGES SHOWN ARE NOT RECOMMENDED.
INDICATES MAXIMUM LOAD – USE CAUTION
LOADS LESS THAN MINIMUM CHARGES SHOWN ARE NOT RECOMMENDED.
INDICATES MAXIMUM LOAD – USE CAUTION
LOADS LESS THAN MINIMUM CHARGES SHOWN ARE NOT RECOMMENDED.
Two More Great 6.5 Creedmoor Reloading Resouces
Want More 6.5 Creedmoor Load Info? View Starline’s 6.5 Creedmoor Guide by Gavin Gear:
PRB 6mm Creedmoor and 6.5 Creedmoor Load Survey
The Precision Rifle Blog compiled Load Data from PRS Competitors, for both 6mm Creedmoor and 6.5 Creedmoor. This is a good place to start. PRB surveyed the match loads for “173 of the top-ranked precision rifle shooters in the country”. CLICK HERE.
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Based on the questions we get on a daily basis on our 800 (Customer Support) line, twist is one of the most misunderstood subjects in the gun field. So let’s look deeper into this mystery and get a better understanding of what twist really means.
When you see the term 1:14″ (1-14) or 1:9″ twist, just exactly what does this mean? A rifle having a 1:14″ twist means the bullet will rotate one complete revolution every fourteen inches of the barrel. Naturally a 1:9″ turns one time every nine inches that it travels down the barrel. Now, here’s something that some people have trouble with. I’ve had calls from shooters thinking that a 1:14″ twist was faster than a 1:9″ because the number was higher with the 1:14″. The easiest way to remember this is the higher the number, the slower the twist rate is.
Now, the biggest misconception is that if a shooter has a .223 with a 1:8″ twist, his rifle won’t stabilize a 55gr bullet or anything lighter. So let’s look at what is required. The longer a bullet is for its diameter, the faster the twist has to be to stabilize it. In the case of the .223 with a 1:8″ twist, this was designed to stabilize 80gr bullets in this diameter. In truth the opposite is true. A 1:8″ will spin a 55gr faster than what is required in order to stabilize that length of bullet. If you have a bullet with good concentricity in its jacket, over-spinning it will not [normally] hurt its accuracy potential. [Editor’s Note: In addition, the faster twist rate will not, normally, decrease velocity significantly. That’s been confirmed by testing done by Bryan Litz’s Applied Ballistics Labs. There may be some minor speed loss.]
Many barrel-makers mark the twist rate and bore dimensions on their barrel blanks.
Think of it like tires on your truck. If you have a new set of tires put on your truck, and they balance them proper at the tire shop, you can drive down a street in town at 35 MPH and they spin perfect. You can get out on the highway and drive 65 MPH and they still spin perfect. A bullet acts the same way.
Once I loaded some 35gr HP bullets in a 22-250 Ackley with a 1:8″ twist. After putting three shots down range, the average velocity was 4584 FPS with an RPM level of 412,560. The group measured .750″ at 100 yards. This is a clear example that it is hard to over-stabilize a good bullet.
Twist-rate illustration by Erik Dahlberg courtesy FireArmsID.com. Krieger barrel photo courtesy GS Arizona.
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Ever wondered what caused a particular bulge or marking on a case? And more importantly, does the issue make the case unsafe for further use? Sierra Bullets Ballistic Technician Duane Siercks offers some insight into various issues and their causes in two Case Diagnostic articles from the Sierra Blog.
Incipient Case-Head Separation
This is a Winchester .308 Win case that has a real issue. This case has a very obvious incipient case head separation in the process of becoming a complete failure.
This is most commonly caused by over-sizing the case causing there to be excess headspace on the case. After a few firings and subsequent re-sizing, this case is just about ready to come completely apart. Proper die adjustment is certainly a requirement here. Of course this case is not safe to reuse.
Excessive Pressure (Load Too Hot)
If you will notice in the picture of the case rim, there are two pressure signs to notice. First, look at the primer. It is basically flattened to about the max of what could be considered safe. If this was the only pressure sign noted, I would probably be fine with this load, but would constantly keep an eye on it especially if I was going to use this load in warmer temperatures. This load could easily cross into the “excess pressure” realm very quickly.
There is another sign of pressure that we cannot ignore. If you’ll notice, there is an ejector mark apparent that is located over the “R” of the R-P headstamp. This absolutely tells us that this load would not have been in the safe pressure range. If there were any of these rounds loaded, they should not be fired and should be dis-assembled. This case should not be reloaded.
Split Case-Neck
Here we have an R-P .22-250 case that has died the death. Everything looks fine with this case except the neck is split. This case must be tossed.
A split neck is a normal occurrence that you must watch for. It is caused by work-hardening of the brass. Brass cases get harder with age and use. Brand new cases that are stored for a period of time can become hard enough that they will split like this case within one to two firings. I have had new factory loads do the same thing. Then as we resize and fire these cases repeatedly, they tend to get harder and harder. Eventually they will split. The life of the case can be extended by careful annealing practices. This is an issue that would need to be addressed in an article by itself. Of course this case is no longer usable.
In the classes that I teach, I try to use examples like this to let the students see what they should be looking for. As always, if we can assist you, whether you are new to reloading or very experienced, contact us here at Sierra Bullets by phone at 1-800-223-8799 or by email at sierra@sierrabullets.com.
Dented Case Body
Here we have a Lake City 7.62×51 (.308 Win.) case with two heavy marks/dents in the case body.
This one may be a bit of a mystery. It appears as if this case may have been caught in the action of a semi-auto rifle when the firearm jammed or the case failed to clear during the cycling process. I probably would not reload this case just to prevent any feeding problems. This also appeared to be a factory loaded round and I don’t really see any pressure issues or damage to the case.
Multiple Problems — Lake City 5.56×45 unknown year.
This case has suffered multiple failures and cannot be re-used. First its has have a very rounded shoulder that is split. Upon first look it was obvious that this round had been a victim of excess pressure. The firearm (perhaps an AR?) was apparently not in full battery, or there was possibly a headspace issue also. While taking a closer look, the primer was very flat and the outside radius of the primer cup had been lost. High pressure! Then I also noticed that there was an ejector mark on the case rim. This is most certainly an incident of excessive pressure. This case is ruined and should be discarded.
It is very important to observe and inspect your cases before each reloading. After awhile it becomes second nature to notice the little things. Never get complacent as you become more familiar with the reloading process. If ever in doubt, call Sierra’s Techs at 1-800-223-8799.
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Sierra Bullets has recently released load data for the 6mm Creedmoor cartridge, a necked-down version of the 6.5 Creedmoor, a popular PRS, tactical, and hunting cartridge. Sierra has released very comprehensive 6mm Creedmoor load data, covering fifteen (15) different bullets from 55 to 110 grains. NOTE: Hornady-brand brass was used for Sierra’s 6mm Creedmoor load tests, not the newer, stronger Lapua 6.5 CM brass with small primer pockets. Hand-loaders using Lapua 6.5 Creedmoor brass necked to 6mm may have to adjust their loads.
Sierra writes: “As soon as the 6.5 Creedmoor was released in 2007, a 6mm version was being envisioned. After the 6mm Creedmoor demonstrated its worth at 1000 yards it began to catch the attention of Precision Rifle Series (PRS) competitors. The 6mm/6.5 Creedmoor is a great fit for those looking for an AR platform-friendly cartridge. It delivers velocities very similar to the .243 Win and yet fits the AR10 magazine length[.] The 30-degree shoulder makes this a very efficient case and helps prolong case life as well. The 6mm/6.5 Creedmoor works well with powders such as H4350, RE-17, and Ramshot Hunter for heavier long-range bullet weights. Slightly faster powders such as RE-15, Win 760, and Vihtavuori N540 work well with lighter weight bullets.”
Sierra Bullets Tested for 6mm Creedmoor Load Data
55gr BlitzKing (#1502)
60gr HP (#1500)
70gr HPBT (#1505)
70gr BlitzKing (#1507)
75gr HP (#1510)
In developing its 6mm Creedmoor load data, Sierra tested a very wide selection of propellants, two dozen overall. For the smaller bullets, fast-burning powders such as Benchmark, H4895, and CFE223 were tested. For the heavier 100+ grain bullets, Sierra tested a selection of medium-burn-rate powders including H4350, Reloder 16, Reloder 17, Varget, and Superformance. Sierra did a very thorough job. We know this information will be welcomed by 6mm Creedmoor shooters.
Don’t know what powder to try first? For the 107-110 grain bullets, if you want best accuracy and low ES/SD, our Forum members recommend Alliant Reloder 16 and Hodgdon H4350. If you are seeking max velocity with the 110-grainer, look at Hodgdon Superformance and Reloder 19.
Here are Sierra’s 6mm Creedmoor Load Data Charts for the 107gr MK and 110gr MK. There are a half-dozen other tables for lighter-weight bullets.
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by Sierra Bullets Ballistic Technician Paul Box
One thing that plays a major role in building an accuracy load is neck tension. I think a lot of reloaders pretty much take this for granted and don’t give that enough thought.
So, how much neck tension is enough?
Thru the years and shooting both a wide variety of calibers and burn rates of powder, I’ve had the best accuracy overall with .002″ of neck tension. Naturally you will run into a rifle now and then that will do its best with something different like .001″ or even .003″, but .002″ has worked very well for me. So how do we control the neck tension? Let’s take a look at that.
First of all, if you’re running a standard sizing die with an expander ball, just pull your decapping rod assembly out of your die and measure the expander ball. What I prefer is to have an expander ball that [can give] you .002″ in neck tension [meaning the inside neck diameter is about .002″ smaller than the bullet diameter after passing the expander through]. If you want to take the expander ball down in diameter, just chuck up your decapping rod assembly in a drill and turn it down with some emery cloth. When you have the diameter you need, polish it with three ought or four ought steel wool. This will give it a mirror finish and less drag coming through your case neck after sizing.
Tips for Dies With Interchangeable Neck Bushings
If you’re using a bushing die, I measure across the neck of eight or ten loaded rounds, then take an average on these and go .003″ under that measurement. There are other methods to determine bushing size, but this system has worked well for me.
Proper Annealing Can Deliver More Uniform Neck Tension
Another thing I want to mention is annealing. When brass is the correct softness, it will take a “set” coming out of the sizing die far better than brass that has become to hard. When brass has been work hardened to a point, it will be more springy when it comes out of a sizing die and neck tension will vary. Have you ever noticed how some bullets seated harder than others? That is why.
Paying closer attention to neck tension will give you both better accuracy and more consistent groups.
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by Tommy Todd, Sierra Bullets Chief Ballistician for Sierra Bullets Blog
I have shot several disciplines of shooting competitions over the years and have learned a few things regarding ammunition and bullet function during this time. Frequently the matches I shoot require 40 to 100 shots before a person gets a chance to clean his rifle. Just as frequently, a good shooting match rifle will still shoot very good scores and groups with that many rounds fired through them. However, those guns do not deliver the same accuracy as when they were clean, but the drop-off in accuracy is not a huge change unless a set of accumulative issues arise.
In one situation, very dirty powder created more serious problems…
Pressure Issues — Extraction Problems Caused by Bad Fouling
Problem: Pressures Increased as Powder Fouled Barrel and Carbon Ring Formed
Solution: Clean Barrel Every Ten Rounds.
I witnessed a set of problems that occurred with a fellow competitor’s rifle at a recent F-Class match. He was using a large case capacity cartridge for the bore diameter and he was shooting a powder that was burning extremely dirty. As the match progressed, the carbon buildup caused most likely a carbon ring in the throat of the rifle and pressures kept increasing to the point that the cases were hard to extract, bolt lift was excessive, and eventually he quit shooting the rifle due to these issues. Accuracy also suffered as could be evidenced by the gun’s performance on target. This load looked fine when he was developing it, none of the excessive pressure signs appeared when he worked the load up, but he was cleaning the gun every ten shots.
When he was shooting multiple, 20-shot strings during the match is when the issues appeared. He was able to give the gun a thorough cleaning and the issues went away, for several rounds and then the pressures started appearing again. These pressure signs were not due to ambient temperatures as it was a cool spring morning and the temperature was in the low 40° range.
Accuracy Issues — Tune Lost with Higher Ambient Temps
Problem: Accuracy Lost When Outside Temp Much Hotter than When Load Developed
Solution: Pull Bullets, Reload Ammo with Lighter Charge
A couple of years ago, I attended a match early in the shooting season and it was unusually hot for that time period. I heard a competitor worrying before the match about his gun “blowing up”. At first I was concerned, but after thinking about what he had said I realized that he meant his “accuracy” blowing up, meaning he knowingly had loaded his ammunition at the top end of an accuracy tune that he established via a ladder test. The next day I asked him how his scores were and he said the gun was not shooting very well initially, but he had found enough equipment from friends that were at the match and had pulled the bullets, reduced the powder charge by a few tenths of a grain and re-seated the bullets and his gun was now shooting normally. The temperature difference between his home range the weekend before when he established his load and the match conditions was about 30 degrees and that was enough to cause an accuracy change at 1000 yards.
To learn more about how ambient temperature (and primer choice) affect pressures (and hence velocities) you should read the article Pressure Factors: How Temperature, Powder, and Primer Affect Pressure by Denton Bramwell. In that article, the author uses a pressure trace instrument to analyze how temperature affects ammo performance. Bramwell’s tests yielded some fascinating results.
For example, barrel temperature was a key factor: “Both barrel temperature and powder temperature are important variables, and they are not the same variable. If you fail to take barrel temperature into account while doing pressure testing, your test results will be very significantly affected. The effect of barrel temperature is around 204 PSI per F° for the Varget load. If you’re not controlling barrel temperature, you about as well might not bother controlling powder temperature, either. In the cases investigated, barrel temperature is a much stronger variable than powder temperature.”
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The 6.5 Creedmoor cartridge is now one of the most popular cartridges for new factory rifles. Ruger, Savage, Howa and other gun-makers all offer 6.5 Creeemoor rifles. The 6.5 CM has been a leading cartridge for tactical/practical gun games (although many shooters have moved to a 6mm Creedmoor or even a 6mm Dasher). It offers excellent ballistics, moderate recoil, and good accuracy with a variety of powder and bullet combos. Along with the 6.5×47 Lapua, the 6.5 Creedmoor has demonstrated that a .264-Caliber mid-sized caliber is truly a jack of all trades — it can be accurate on paper, win PRS matches, and also harvest game during hunting season. If you own a 6.5 Creedmoor (or plan to get one) and hand-load your ammo, this post should provide a good start. Sierra Bullets now offers 6.5 Creedmoor Load Data for bullets from 120 to 142 grains — the most popular weight range for this chambering.
Sierra Bullets has released very complete load data for the popular 6.5 Creedmoor cartridge. This medium-sized cartridge has become one of the most popular chamberings for tactical and PRS shooters. The 6.5 Creedmoor combines excellent accuracy, good mag-feeding, good barrel life, moderate recoil, and reasonable component cost. That’s why this cartridge has caught on quickly.
The Springfield M1A is now available in 6.5 Creedmoor. For Gas Guns like this, be sure to full-length-size your brass after every firing, with adequate shoulder bump.
Developed in 2007 by Dennis DeMille and Dave Emary, the 6.5 Creedmoor is a shortened and improved 30 TC cartridge case that was inspired by the .308 Winchester design. This short action design was created to maximize case capacity and a wide range of loading lengths, while still fitting in standard short action magazines. With the correct twist barrel, the versatile 6.5 Creedmoor can take advantage of the wide range of bullet weights available in 6.5 mm (i.e. .264 caliber).
Reloaders should keep in mind that the 6.5 Creedmoor works best with medium to medium-slow powders such as H4350, Reloder 16, Varget, and IMR 4451. The light recoil and adaptability of the efficient 6.5 Creedmoor cartridge has already proven itself in high power and PRS matches, and in the hunting fields. Couple that with respectable barrel life and its intrinsic accuracy potential and you have a recipe for success.
Here are three tables from the Sierra Bullets Reloading Manual (5th Edition). IMPORTANT — This is just a sample!! Sierra has load data for many other 6.5mm bullet types, including FB, Spitzer, SBT, HPBT, and Tipped MK from 85 grains to 142 grains. To view ALL 6.5 Creedmoor DATA, CLICK HERE.
INDICATES MAXIMUM LOAD – USE CAUTION
LOADS LESS THAN MINIMUM CHARGES SHOWN ARE NOT RECOMMENDED.
INDICATES MAXIMUM LOAD – USE CAUTION
LOADS LESS THAN MINIMUM CHARGES SHOWN ARE NOT RECOMMENDED.
INDICATES MAXIMUM LOAD – USE CAUTION
LOADS LESS THAN MINIMUM CHARGES SHOWN ARE NOT RECOMMENDED.
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At the request of our readers, we provide select “Deals of the Week”. Every Monday morning we offer our Best Bargain selections. Here are some of the best deals on firearms, hardware, reloading components, optics, and shooting accessories. Be aware that sale prices are subject to change, and once clearance inventory is sold, it’s gone for good. You snooze you lose.
1. Midsouth — Frankford Arsenal Rotary Tumbler LITE, $99.99
Wet-tumbling with stainless media gets large quantities of cartridge brass clean inside and out. If you’ve wanted to try wet-tumbling, here’s your chance. Midsouth has the Frankford Arsenal Platinum LITE Tumbler on sale for just $99.99 — a total steal. If you run large quantities of brass, you can get the larger-capacity Frankford Arsenal Platinum Tumbler for $179.99. Either one of these is a reliable, durable (and watertight) machine that should provide years of worry-free tumbling.
2. Grizzly Bald Eagle — Great Range Bag and Rifle Case Sale
Grab one of these Bald Eagle rifle cases or range bags at up to 50% off. These are way better than typical too-skinny rifle cases or flimsy fabric bags. The rifle cases have plenty of storage for your match needs and the padding is very good. The box-style range bags have thick closed-cell foam panels in the base, top, and sides. That gives these bags good “wall strength”, so they don’t collapse like typical range bags. These are more like a quality camera-case.
AccurateShooter.com Editor’s Bald Eagle 20″ Range Bag with Spotting Scope:
As you can see, the Bald Eagle 20″ range bag is quite big inside with lots of padding. We use this bag to carry our spotting scope and a small tripod, plus lots of other gear in the pockets. The near-full-width front pocket is very handy. We really like this 20″ range bag, which is a total steal at just $15.97. In fact the Editor likes his 20″ Bald Eagle bag so much he just ordered a second, along with two 15″ bags.
3. Graf’s — Frankford Arsenal M-Press + Extras, $249.99
Frankford Arsenal has been getting a lot of press since SHOT Show with a bounty of new products. Topping the list of must-have items is the M-Press. This press takes all the proven concepts of a Co-Axial press and improves on them. It has reversible cam-over bars plus an LED light, quick-adjusting shell-holders, and many other notable features. Right now Grafs.com is offering the new Frankford M-Press for $249.99. If you need any more incentive, Graf’s is offering a FREE set of three (3) additional die blocks, plus a handy kinetic bullet puller. Nobody else is offering anything like this especially since the M-Press is so new. [Editor: Watch for our M-Press review later this month.]
4. Midsouth — Sierra Loaded Ammunition Sale
Sierra is renowned for making quality bullets but did you know Sierra also produces great loaded ammo for hunters? Available in many of the most popular calibers and featuring GameKing bullets, Sierra’s GameChanger Ammunition could just be the edge you’re looking for on your next hunt. Midsouth has GameChanger ammo on sale right now. Stock up before hunting season arrives and prices go up.
5. Bruno Shooters Supply — Nightforce NXS 5.5-22 Scope, $1699
Nightforce NXS scopes are some of the best optics in their price range. Given their popularity, it’s rare to find NXS models on sale. Right now Bruno’s is discounting these fine scopes, so this is a great buying opportunity. Grab either the Nightforce NXS 5.5-22x50mm or the Nightforce NXS 5.5-22x56mm at a blow out price of $1699. This power range is one of the most popular out there so to buy one of these for over $300 off is a deal you can’t pass up.
6. Bullet Central — Bix’N Andy Trigger with Free Cleaning Kit
Bix’N Andy makes some of the very best trigger systems on the planet. It’s rare that you ever see them associated with any kind of promotion. If you’ve been waiting for a good reason to get a Bix’N Andy trigger, here is your chance. Bullet Central is now offering a free 8 oz. ThorroClean kit with every Bix’N Andy purchase. ThorroClean by Iosso works is a two-part bore flush/bore cleaning package that removes fouling with minimal dwell time. Trust us, you won’t be disappointed with a Bix’N Andy trigger, and the deal provides a little extra incentive.
7. Amazon — 60 Jourdak Quality Earplugs for $12.95
Ever arrived at the range and realized you left your earmuffs at home? It’s happened to us all. That’s why you should keep some extra ear-plugs in your rifle cases and range bags. Right now you can buy a 60-count bottle of Jourdak soft earplugs for $12.95. Buyers say these SNR 35 dB plugs, which “heat-mold” to your ear canal, are very comfortable and effective. Plus there is a 10% Off instant coupon for the Jourdaks. We also recommend the Howard Leight Max-1 ear-plugs. These NRR 33 plugs are comfortable and easy to insert. You can get 20 pairs of Max-1s for just $4.95. Either option comes with free shipping. Remember, always wear effective hearing protection while at the range.
TECH NOTE Concerning NRR (Noise Reduction Rating) and SNR (Single Number Rating)
The highest NRR rating for earplugs is 33, and the highest available NRR rating for earmuffs is 31. These values reflect the level of noise protection available for each device when worn alone. Combining earplugs with earmuffs can offer a NRR protection level of 36. The SNR (single number rating) is a rating system used in the European Union to indicate the amount of protection offered by correctly-fitted hearing protection devices. Source: Protectear.com
8. Palmetto State Armory — S&W M&P 15-22, $299.99
In our view, every gun guy (and gun gal) should own a nice self-loading .22 LR rimfire rifle. And if you own an AR, it makes sense to have a rimfire rig with the same balance and ergonomics. That’s what the M&P 15-22 is all about — AR ergos with rimfire economy. With bulk .22 LR ammo, your cost-per-shot is under nine cents per round! Right now at Palmetto State Armory, the popular Smith & Wesson M&P 15-22 Sport is just $299.99 on sale. That’s not much more than a basic Ruger 10/22 and we like this S&W 15-22 much better — it’s great for plinking and rimfire action disciplines. This rifle can use most AR15-family accessories, and it comes with Magpul MBUS sights, and M-Lok rails.
9. Amazon — TACVASEN Long Sleeve Tactical Shirt, $29.99
Let’s face it, looking good at a match can be almost as important as feeling good. Now you can do both with lightweight TACVASEN Long Sleeve Shirts. The TACVASEN Men’s Slim Fit Long Sleeve Combat Shirt is available in nine different colors, including four with camo sleeves. PRS guys would like these shirts. They fit right so you can run stages without snagging range carts or barriers. These zip-collar shirts feature 65% polyester, 35% cotton fabric for breathability and quick drying. These shirts have earned a 4-star rating with 163 buyer reviews.
Are you considering the Frankford Arsenal tumbler featured above? It’s a great machine. But you’ll also need stainless media for it. Here’s your solution. Amazon sells 2.5 lbs of stainless tumbling media for a mere $19.50. Amazon also offers even larger quantities of stainless steel tumbling pins if you need more than a couple pounds for those really big jobs.
Weekly Deals sourced by F-Class John.
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Developed in 2007 by Dennis DeMille and Dave Emary, the 6.5 Creedmoor is a shortened and improved 30 TC cartridge case that was inspired by the .308 Winchester design. This short action design was created to maximize case capacity and a wide range of loading lengths, while still fitting in standard short action magazines. With the correct twist barrel, the versatile 6.5 Creedmoor can take advantage of the wide range of bullet weights available in 6.5 mm (i.e. .264 caliber). Reloaders should keep in mind that the 6.5 Creedmoor works best with medium to medium-slow powders such as H4350, Varget, Win 760, and RE-17. The light recoil and adaptability of the efficient 6.5 Creedmoor cartridge has already proven itself in high power, precision rifle series and benchrest competitions. Couple that with respectable barrel life and its intrinsic accuracy potential and you have a recipe for success which should insure its legacy for decades to come.
To learn more about how ambient temperature (and primer choice) affect pressures (and hence velocities) you should read the article 
