June 14th, 2019

TECH Tip: How to Reduce Run-Out with Seating Dies

USAMU Hump Day Reloading TIR run-out concentricity seating die stem

Each Wednesday, the U.S. Army Marksmanship Unit publishes a reloading “how-to” article on the USAMU Facebook page. A while back the USAMU’s reloading gurus looked at the subject of cartridge run-out and what can be done to produce straighter ammo. Tasked with producing thousands of rounds of ammo for team members, the USAMU’s reloading staff has developed smart methods for improving concentricity, even with budget=price dies. For other hand-loading tips, visit the USAMU Facebook page.

Minimizing Runout with Standard Seating Dies

This USAMU article explains how to set up standard bullet seating dies dies to minimize Total Indicated Run-out (TIR). The loading process is described using a single-stage press since most handloaders have one. A high-quality run-out gauge is essential for obtaining consistent, accurate results.

Having sized, primed, and charged our brass, the next step is bullet seating. Many approaches are possible; one that works well follows. When setting up a standard seating die, insert a sized, trimmed case into the shellholder and fully raise the press ram. Next, back the seating stem out and screw the die down until the internal crimping shoulder touches the case mouth.

Back the die out ¼ turn from this setting to prevent cartridge crimping. Next, lower the press ram and remove the case. Place a piece of flat steel (or window glass, which is quite flat) on the shellholder and carefully raise the ram.

Place tension on the die bottom with the flat steel on the shellholder. This helps center the die in the press threads. Check this by gently moving the die until it is well-centered. Keeping light tension on the die via the press ram, secure the die lock ring. If one were using a match style, micrometer-type seating die, the next step would be simple: run a charged case with bullet on top into the die and screw the seating stem down to obtain correct cartridge OAL.

However, with standard dies, an additional step can be helpful. When the die has a loosely-threaded seating stem, set the correct seating depth but don’t tighten the stem’s lock nut. Leave a loaded cartridge fully raised into the die to center the seating stem in the die. Then, secure the stem’s lock nut. Next, load sample cartridges and check them to verify good concentricity.

USAMU Hump Day Reloading TIR run-out concentricity seating die stem

One can also experiment with variations such as letting the seating stem float slightly in the die to self-center, while keeping correct OAL. The run-out gauge will show any effects of changes upon concentricity. However, this method has produced excellent, practical results as evidenced by the experiment cited previously. These results (TIR Study 2) will reproduced below for the reader’s convenience.

First, however, let’s examine run-out figures of some factory-loaded match ammunition. This should give readers who are new to TIR gauges some perspective about the TIR ranges one might encounter.

TIR Study 1: 50 rounds Lake City M852 Match 7.62mm
(168 gr. Sierra MatchKings)
0.000” – 0.001” = 2%
0.001” – 0.002” = 30%
0.002” – 0.003” = 16%
0.003” – 0.004” = 22%
0.004” – 0.005” = 14%
0.005” – 0.006” = 14%
0.006” – 0.007” = 0%
0.007” – 0.008” = 2%

TIR Study 2: 50 rounds of .308 match ammo loaded using carefully-adjusted standard dies, vs. 50 using expensive “Match” dies from the same maker.

Standard dies, TIR:
0.000” — 0.001” = 52%;
0.001”– 0.002” = 40%;
0.002”– 0.003” = 8%.
None greater than 0.003”.

Lesser-quality “Match” dies, TIR:
0.000”– 0.001” = 46%;
0.001” — 0.002” = 30%;
0.002” — 0.003” = 20%;
0.003” — 0.004” = 4%.

Note: both samples were loaded using the O-Ring method, i.e. with a rubber O-Ring placed under the locking ring of the Full-length sizing die to allow that die to float.

These tips are intended to help shooters obtain the best results from inexpensive, standard loading dies. Especially when using cases previously fired in a concentric chamber, as was done above, top-quality match dies and brass can easily yield ammo with virtually *no* runout, given careful handloading.

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June 14th, 2019

Democrats Revive Legislative Attack on American Gun Makers

PLCAA Congress Senate Protection Lawful Commerce Repeal Gun Violence Act

Another legislative attack on the firearms industry is being pushed in Congress by Democratic party politicians. Rep. Adam Schiff (D-CA) and Sen. Richard Blumenthal (D-CT) reintroduced legislation this week that targets the gun industry, allowing persons to sue the makers of firearms that were used by criminals to cause injury. Currently, such lawsuits are blocked by the Protection of Lawful Commerce in Arms Act (PLCAA) enacted in 2005.

The new Democratic legislation, the “Access to Justice for Victims of Gun Violence Act”, would repeal the PLCAA. If the PLCAA is repealed, then gun-makers could potentially be sued for the actions of criminals using firearms — even if the guns were stolen. If bad guys cause harm with guns, the Democrats want the gun-makers to pay, and keep paying. The goal is to eventually bankrupt the gun industry and put companies such as Colt, Ruger, and Smith & Wesson out of business.

The Democrats have gone after the PLCAA before. NPR reports: “The effort to repeal PLCAA by Democrats on Capitol Hill is not new. Schiff first introduced the measure in 2013, and it has been reintroduced at least two other times without gaining traction.”

The real goal of this legislation is to cripple the gun industry. GunAmerica Digest explains: “One of the primary goals of anti-gunners is to bankrupt the gun industry by repealing the Protection of Lawful Commerce in Arms Act (PLCAA).”

The sponsors of the new legislation claim their legislation is needed to protect citizens. Congressman Schiff (D-CA) declared: “This bill would pierce the gun industry’s liability shield by putting an end to the special protections the gun industry receives when they shirk their fundamental responsibility to act with reasonable care for the public safety.”

GunsAmerica Digest says don’t believe this: “Schiff and Blumenthal are grossly mis-characterizing the purpose of PLCAA. It does NOT protect members of the gun industry from product liability suits for manufacturing or design defects or certain types of negligent conduct. It merely prohibits lawsuits against gun makers for damages resulting from the third-party criminal misuse of their firearms.”

It’s clear what the sponsors of this legislation really want. They seek to destroy the U.S. gun industry through waves of lawsuits — “death by 1000 cuts”. The anti-gunners may not be able to remove the Second Amendment from the Bill of Rights, but if they succeed in bankrupting all the major gun-makers, then the “Right to Keep and Bear Arms” won’t be worth much.

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