July 31st, 2020

Grip on Bullet — Many Factors Involved, Not Just Bushing Size

case neck bushing reloading die tension bullet release

Many novice hand-loaders believe that neck bushing Inside Diameter (ID) size is the only important factor in neck tension. In fact, many different things will influence the grip on your bullet and its ability to release from the case neck. To learn more about neck tension and “case grip”, take the time to read this article carefully. We bet you’ll gain knowledge that will let you load more accurate ammo, with better ES/SD.

Editor: Guys, this is a VERY important article. You really should read it over carefully, twice. Variations in the force required to release a bullet can significantly affect accuracy and ES/SD. You really need to know how the grip on bullet can be altered by many different factors.

Neck Tension (i.e. Grip on Bullets) Is a Complex Phenomenon
While we certainly have considerable control over neck tension by using tighter or looser bushings (with smaller or bigger Inside Diameters), bushing size is only one factor at work. It’s important to understand the multiple factors that can increase or decrease the resistance to bullet release. Think in terms of overall brass-on-bullet “grip” instead of just bushing size (or the internal neck diameter in non-bushing full-length sizing dies).

Bullet grip is affected by many things, such as:

1. Neck-wall thickness.
2. Amount of bullet bearing surface (shank) in the neck.
3. Surface condition inside of neck (residual carbon can act as a lubricant; ultrasonic cleaning makes necks “grabby”).
4. Length of neck (e.g. 6mmBR neck vs. 6mm Dasher).
5. Whether or not the bullets have an anti-friction coating.
6.The springiness of the brass (which is related to degree of work-hardening; number of firings etc.)
7. The bullet jacket material.
8. The outside diameter of the bullet and whether it has a pressure ridge.
9. Time duration between bullet seating and firing (necks can stiffen with time).
10. How often the brass is annealed.
11. Amount (length) of neck sized (e.g. you can size only half the neck).
12. Interior diameter of bushing, or neck section of non-bushing die.


– and there are others…

One needs to understand that bushing size isn’t the beginning and end of neck tension questions, because, even if bushing size is held constant, the amount of bullet “grip” can change dramatically as the condition of your brass changes. Bullet “grip” can also change if you alter your seating depth, and it can even change if you ultrasonically clean your cases.

Redding neck bushingsIn our Shooters’ Forum a reader recently asked: “How much neck tension should I use?” This prompted a Forum discussion in which other Forum members recommended a specific number based on their experience, such as .001″, .002″, or .003″. These numbers, as commonly used, correspond to the difference between case-neck OD after sizing and the neck OD of a loaded round, with bullet in place. In other words, the numbers refer to the nominal amount of interference fit (after sizing).

While these commonly-used “tension numbers” (of .001″, .002″ etc.) can be useful as starting points, neck tension is actually a fairly complex subject. The actual amount of “grip” on the bullet is a function of many factors, of which neck-OD reduction during sizing is just one. Understanding these many factors will help you maintain consistent neck tension as your brass “evolves” over the course of multiple reloadings.

Seating Depth Changes Can Increase or Decrease Grip on Bullet
You can do this simple experiment. Seat a boat-tail bullet in your sized neck with .150″ of bearing surface (shank) in the neck. Now remove the bullet with an impact hammer. Next, take another identical bullet and seat it with .300″ of bearing surface in another sized case (same bushing size/same nominal tension). You’ll find the deeper-seated bullet is gripped much harder.

PPC lapua brassNeck-Wall Thickness is Important Too
I have also found that thinner necks, particularly the very thin necks used by many PPC shooters, require more sizing to give equivalent “grip”. Again, do your own experiment. Seat a bullet in a case turned to .008″ neckwall thickness and sized down .003″. Now compare that to a case with .014″ neckwall thickness and sized down .0015″. You may find that the bullet in the thin necks actually pulls out easier, though it supposedly has more “neck tension”, if one were to consider bushing size alone.

In practical terms, because thick necks are less elastic than very thin necks, when you turn necks you may need to run tighter bushings to maintain the same amount of actual grip on the bullets (as compared to no-turn brass). Consequently, I suspect the guys using .0015″ “tension” on no-turn brass may be a lot closer to the guys using .003″ “tension” on turned necks than either group may realize.

Toward a Better Definition of Neck Tension
As a convenient short-cut, we tend to describe neck tension by bushing size alone. When a guy says, “I run .002 neck tension”, that normally means he is using a die/bushing that sizes the necks .002″ smaller than a loaded round. Well we know something about his post-sizing neck OD, but do we really have a reliable idea about how much force is required to release his bullets? Maybe not… This use of the term “neck tension” when we are really only describing the amount of neck diameter reduction with a die/bushing is really kind of incomplete.

My point here is that it is overly simplistic to ask, “should I load with .001 tension or .003?” In reality, an .001″ reduction (after springback) on a thick neck might provide MORE “grip” on a deep-seated bullet than an .003″ reduction on a very thin-walled neck holding a bullet with minimal bearing surface in the neck. Bushing ID is something we can easily measure and verify. We use bushing size as a descriptor of neck tension because it is convenient and because the other important factors are hard to quantify. But those factors shouldn’t be ignored if you want to maintain consistent neck tension for optimal accuracy.

Consistency and accuracy — that’s really what this all about isn’t it? We want to find the best neck tension for accuracy, and then maintain that amount of grip-on-bullet over time. To do that you need to look not only at your bushing size, but also at how your brass has changed (work-hardened) with time, and whether other variables (such as the amount of carbon in the neck) have changed. Ultimately, optimal neck tension must be ascertained experimentally. You have to go out and test empirically to see what works, in YOUR rifle, with YOUR bullets and YOUR brass. And you may have to change the nominal tension setting (i.e. bushing size) as your brass work-hardens or IF YOU CHANGE SEATING DEPTHS.

Remember that bushing size alone does not tell us all we need to know about the neck’s true “holding power” on a bullet, or the energy required for bullet release. True bullet grip is a more complicated phenomenon, one that is affected by numerous factors, some of which are very hard to quantify.

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July 31st, 2020

Vortex Diamondback HD — New Affordable Spotting Scopes

Vortex diamonback spotter spotting scope HD

Vortex’s new Diamondback® HD series of spotting scopes offer impressive performance for the price. While you can spend $2500 or more for a premium Fluorite Glass spotter, Vortex’s new HD spotting scopes cost $500-$600 MSRP. These new Diamondback spotters could be affordable options for competitive shooters and hunters. The Diamondback HD line of spotting scopes include both angled and straight body types in 16-48x65mm and 20-60x85mm configurations.

Vortex diamonback spotter spotting scope HD

The new Diamondback HD spotters employ an HD optical system with multi-coated lenses. Vortex claims these spotters offer greater light transmission, reduced chromatic aberration, better color fidelity, and enhanced sharpness. Vortex says the “crisp resolution, brighter images, and edge-to-edge sharpness [can reduce] eye strain during long glassing sessions.” We hope to test the 20-60x85mm model to confirm these claims. HD glass should deliver greater low-light performance and clarity.

These new Diamondback HD models boast design upgrades to make them more like Vortex’s higher-end Viper HD Spotting Scopes (which start at $1049.99 MSRP). The big change is the new full-diameter focus ring as you would see on a Swarovski spotter. Vortex says: “[We] took a fresh approach to the spotter’s exterior, introducing a streamlined, snag-free profile. The helical focus wheel provides fast, fine adjustments, and an Arca-Swiss compatible foot means the Diamondback® HD mounts quickly to compatible tripod heads without additional plates. Plus, a neoprene cover comes included, keeping your spotter protected in the field.” The video below reviews the main design features of the new spotters:

Vortex diamonback spotter spotting scope HD

Which model should you choose? The 16-48x65mm ($499.99 MSRP) is smaller and lighter, making it easier to pack or move around the firing line. The angled 16-48X spotter OAL is 14.25″ and weight is 49.8 oz., making this a good choice for competition shooters looking for an affordable spotter to watch mirage and shot markers. For hunters and other shooters seeking enhanced low-light performance and magnification, the 20-60x85mm ($599.99 MSRP) offers more light-gathering for just $100.00 more. OAL is 16.0″ and weight is 60.9 oz., about 3/4 pound heavier than its smaller brother. You make the choice.

Vortex diamonback spotter spotting scope HD

Vortex diamonback spotter spotting scope HD

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July 31st, 2020

Democrat Party Platform Includes Radical Anti-Firearms Policies

Democratic National Committee DNC 2020 biden NSSF beto

Presumed Democratic presidential nominee, Joe Biden, called the firearm industry “the enemy” from the debate stage one year ago. Now the Democratic Party’s Official Platform lays out an agenda to dismantle the firearm and ammunition industry and destroy Second Amendment rights in America.

How do the Democrats plan to attack your gun rights? CLICK HERE to find out. The Democratic National Committee (DNC) posted the party’s draft platform online. This platform will be formally adopted during the Democratic convention in Milwaukee in mid-August. Just two paragraphs of the 80-page document are dedicated to firearms, but the message is clear. The DNC Draft Platform includes:

  • Halting and criminalizing online firearm and ammunition sales
  • Forcing states to require licenses for owning any firearms
  • Instituting delay processes for background checks
  • Criminalizing private firearm transfers
  • Banning the manufacture and sale of modern sporting rifles
  • Banning the manufacture and sale of 10+ Rd capacity magazines
  • Enacting ex parte “red flag” laws to seize guns without legal recourse
  • Mandating home storage requirements under penalty of law
  • Repealing the Protection of Lawful Commerce in Arms Act

Democratic National Committee DNC 2020 biden NSSF beto

Require Licenses for Firearm Ownership
The right to “keep and bear arms” is a fundamental right recognized by the Second Amendment of the U.S. Constitution. However, the Democrats want to restrict Second Amendment freedoms by requiring that all Americans first obtain a license before being allowed to purchase any firearms. This licensing scheme would be carried out by incentivizing “states to enact licensing requirements to own firearms[.]

Biden politics DNC democratic platform convention

Ban and Confiscate ARs and other Modern Sporting Rifles
The DNC platform contemplates the confiscation of modern sporting rifles. Biden has told voters he would appoint former U.S. Rep. Robert Francis “Beto” O’Rourke as his gun control sheriff, after O’Rourke said “Hell, yes…” to forcibly confiscating modern sporting rifles. Biden answered CNN’s Anderson Cooper when he asked if his federal buyback plan would mean the government would confiscate firearms. “Bingo,” Biden said. “You’re right, if you have an assault weapon. The fact of the matter is they should be illegal, period.”

Biden O'Rourke

Authorize Delays in FBI NICS Background Check System
Changes called for in the DNC platform will cause delays in the FBI’s National Instant Criminal Background Check System for gun sales. Right now, 91% of all NICs background checks are completed within a few minutes. Just 9% are delayed. Of those, 88% are finalized within three working days. The Democrats want to see background checks held up and delayed for many reasons.

Repeal of Protections for Gun Makers against Litigation
The DNC also seeks to revoke the Lawful Commerce in Arms Act, which blocks lawsuits against gun-makers arising from criminal activity by individuals. Such lawsuits threaten a vital American industry. Allowing a lawsuit against a firearms company for the actions of a deranged criminal would be like allowing a lawsuit against an automaker if a drunk driver runs a red light or deliberately runs over a pedestrian. The maker of the car, or firearm, should NOT be financially responsible for the illegal actions of product users.

This story is based on NSSF News Release

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