January 11th, 2018

Heavy Metal — New Cast-Iron Presses from Lyman for 2018

Lyman Cast Iron 0-Ring Victory Press single-stage All-American Turret 8-stage

Lyman is introducing three new Brass Smith series reloading presses for 2018. Here we focus on the two full-size Brass Smith presses, the O-Frame Victory Single Stage and the new 8-Station All-American Turret Press. Both these sturdy presses feature an innovative “straight line” priming system with shielded primer tube.

New Cast-Iron Victory O-Frame Single-Stage Press

Lyman’s new Victory™ Press is built on a heavy duty cast iron “O” frame with 1-inch diameter ram and compound linkage. It looks strong and Lyman claims the “Victory Press is one of the most rugged and rigid available on the market.” The Victory Press features a simple, reliable straight-line primer feed. It’s easy to prime a case — simply push the priming arm forward to position a primer beneath the shell holder. As an added safety feature, the primer feed comes with a heavy steel shield surrounding the primer tube. The large 5-inch frame opening can take long magnum cases. MSRP is $199.45. We expect initial “street price” to be around $160.00, less expensive than an RCBS RockChucker, but more pricey than a Lee Classic Cast Press.

Lyman Cast Iron 0-Ring Victory Press single-stage All-American Turret 8-stage

“It has been a while since Lyman Products introduced new presses, for the very simple reason that our presses are built to be so durable that they actually end up being handed down in families”, explained Trevor Mullen, Lyman’s VP of Marketing and Business Development. “But for 2018, we decided we needed to add certain features that make these new presses even better than their former models.”

New Cast-Iron 8-Station All-American Turret Press

Along with its new Victory Single-Stage Press, Lyman is releasing a beefy All-American Turret Press with eight (8) stations. That’s one more than the Redding T-7 Turret Press, and two more stations than the six-station RCBS Turret Press. With the Lyman’s EIGHT stations you can hold sizing AND seating dies for four different rifle cartridges. Or, if you seat bullets with an arbor press, you could have sizers for six cartridges, plus a dedicated decapping die and a factory crimp die. With eight stations available — there are countless options.

Lyman Cast Iron 0-Ring Victory Press single-stage All-American Turret 8-stage

Rigidity is very important with a turret press — if you have too much “give” of flex with the turret head you may get inconsistent results when bumping shoulders using full-length dies. With a heavy cast-iron frame and turret head, Lyman says its new Turret Press is “the most rugged” on the market. We like the front-mount priming system which can easily be operated with your free hand, whether you mount the press arm on the left or the right. MSRP is $249.95. We expect “street price” to be around $220.00, quite a bit less than the six-station RCBS Turret Press.

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January 11th, 2018

Why Does Load Data Vary Between Reloading Manuals?

load manual sierra reloading hornady data

Written by Sierra Bullets Ballistic Technician Duane Siercks
One of the first things new reloaders notice is that load data varies between reloading manuals. The Sierra Bullets Technicians frequently get inquiries asking us to explain why the load data appears to be inconsistent. This article explains five key factors that can influence published load data.

Example of load data variances for two 168 grain bullets:

Sierra Reloading Manual Hornady Load Reloading

Here are five reasons why the load data varies:

The Bullet
Basically, the similarities in the .30 caliber 168 grain Match bullets (for example) end with weight and diameter. The bullets likely have dimensional differences such as bearing surface length. Bearing surface has a large effect on pressure and velocity. There are also differences in boat tail, flat base, ogive and over-all lengths, which each help determine the cartridge over-all-length (COAL). With different COAL’s, we can expect changes in pressure and velocity also. In some calibers there are differences in bullet diameter with different bullet manufacturers.

It is also worth noting that bullet manufacturers do not all use the same copper alloy for their jackets. This produces more or less friction that results in load pressures and velocities. The solid copper bullets also vary quite a bit in comparison to a lead core and copper jacketed bullet.

The Gun
Each gun is unique, even if you are using the same make, model, and caliber. Special consideration should be used to consider that not all firearm chambers are the same either, creating more variables that need consideration. There can be drastic differences in the throat length. This controls the amount of “jump” that a bullet experiences when the cartridge is fired.

The Powder
Within normal manufacturing tolerances, you can see some variation in a given powders burn rate between different lots of the same powder. So naturally when two different Manuals are produced, it would be doubtful that the same lots would be tested.

The Cartridge Cases
New cases are almost always near minimum specs in dimension. A load fired in a new case would likely have slightly more pressure that when fired in a re-sized case. This would certainly be true if we were loading into fire-formed cases that have had minimal re-sizing done. Fired cases that are full length resized most of the time be slightly larger than the new unfired cases. This gives you differences in case capacity. The same powder charge placed within a new case and a full length resized case will produce different pressure levels and probably different velocities.

Conditions
Temperature can cause pressure increases or decreases. Hot temperatures tend to cause pressures to increase, while cold temperatures will usually do the opposite. Humidity and altitude can impact pressures and velocities likewise.

Conclusion
As you can see, an amazing number of variables effect any load combination. With the differences in the manuals, you’re just seeing firsthand examples of what took place when the data was collected with that particular set of components and firearm. Think of a reloading manual as a report. In essence, a reloading manual says, “We tried this particular component combination, and these are the results we obtained.”

Remember that you may or may not reach the same maximum load safely. There is no “one load fits all bullets.” The minimum load data offers a safe place to start. The maximum load data listed should always be regarded as a safety guideline and not necessarily a goal! Your gun should shoot accurately without breaching the maximum load data. The best advice is: always start low and work your load up!

If you have questions about variances in load data or other reloading questions, please call our ballistic technicians at 1-800-223-8799 or send us an email at sierra [at] sierrabullets.com.

Sierra Bullets Blog reloading information

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January 11th, 2018

Guide to Gun Metals — What You Need to Know

Sweeney Guide to Gun Metal

4140, 4150, 316, 17-4, 6061, 7075-T6 — What is the significance of these numbers? No, they’re not winning lottery numbers. These are all designations for metals commonly used in firearm and barrel construction. 4140 and 4150 are carbon steels, with 4150 often used in mil-spec AR15 barrels. 316 and 17-4 are grades of stainless steel. 316 is “marine grade” stainless, while 17-4 has 17% chromium and 4% nickel. 17-4 is a harder steel used in barrels and receivers. 6061 and 7075-T6 are aluminum alloys. 6061 is “aircraft grade” aluminum, often used for rings and trigger guards, while 7075-T6 is a much stronger, heat-treated aluminum commonly used in AR15 uppers.

Sweeney Guide to Gun MetalYou can learn about all these metals (and more) in the online archives of RifleShooter magazine.

Written by Patrick Sweeney, RifleShooter’s Guide to Gun Metal summarizes the primary types of steel and aluminum used in gun and barrel construction. Sweeney explains the nomenclature used to define metal types, and he outlines the salient properties of various steel and aluminum alloys. This is a useful resource for anyone selecting components or building rifles. We recommend you print out the page, or at least bookmark it.

Metals by the Number
The number system for steel classification came from the auto industry. Sweeney explains: “The Society of Automotive Engineers uses a simple designating system, the four numbers you see bandied about in gun articles. Numbers such as 1060, 4140 or 5150 all designate how much of what [elements are] in them. The first number is what class—carbon, nickel, chromium, and so forth. The next three numbers [list other elements in the alloy]. 4140, also known as ordnance steel, was one of the early high-alloy steels. It has about 1 percent chromium, 0.25 percent molybdenum, 0.4 percent carbon, 1 percent manganese, around 0.2 percent silicon and no more than 0.035 percent phosphorus and no more than 0.04 percent sulphur. That leaves most of it, 94.25 percent, iron.”

Aluminum Alloys
Numbers are also used to differentiate different types of aluminum alloys. Sweeny writes: “Aluminum is used in firearms in two alloys: 7075 and 6061. 6061 is commonly referred to as ‘aircraft aluminum’ and has trace amounts of silicon, copper, manganese, molybdenum and zinc. 7075 is a much stronger alloy and has markedly larger amounts of copper, manganese, chromium and zinc.” 7075 Aluminum has significantly better corrosion resistance, and that’s why it is used for AR receivers. The “T6″ you often see appended to 7075 refers to a heat-treating process.

Aluminum (or “Aluminium” in the UK) is a chemical element in the boron group with symbol Al and atomic number 13. It is a silvery-white, soft, nonmagnetic, ductile metal. Aluminum is the third most abundant element, and the most abundant metal, in the Earth’s crust. (Wikipedia)

Aluminum alloy table chart Silicon Maganese Zinc Copper Magnesium

To learn more about the metals used in your firearms’ barrels, rings, receivers, and internal parts, read Sweeney’s article in RifleShooterMag.com. Taking the time to read the article from start to finish will expand your knowledge of metal properties and how metals are chosen by manufacturers and gunsmiths. CLICK to Read Guide to Gun Metal.

Story Tip by EdLongrange. We welcome reader submissions. Aluminum Alloy chart courtesy AluminiumDesign.net.
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