June 22nd, 2018

How to Improve Case Concentricity with Standard Seating Dies

USAMU Handloading Hump Day Seating Die Adjustment Stem TIR Concentricity Run-out

Each Wednesday, the U.S. Army Marksmanship Unit publishes a reloading “how-to” article on the USAMU Facebook page. This USAMU “Handloading Hump Day” article, the second in a series on improving concentricity, has many useful tips. If you use standard (non-micrometer) seating dies when loading some cartridge types, this article is worth reading. And visit the USAMU Facebook page next Wednesday for the next installment.

Once again, it’s time for USAMU’s “Handloading Hump-Day!” Last week, we addressed achieving very good loaded-cartridge concentricity (AKA “TIR”, or Total Indicator Runout) using standard, “hunting grade” reloading dies.

We explained how to set up the Full-Length Size die to float slightly when correctly adjusted for desired case headspace. We also cited a study in which this method loaded ammunition straighter than a set of [higher grade] match dies from the same maker. [One of the keys to reducing TIR with both sets of dies was using a rubber O-ring below the locking ring to allow the die to float slightly. READ Full-Length Sizing Die TIP HERE.]

Now, we’ll set up a standard seating die to minimize TIR — the other half of the two-die equation. As before, we’ll use a single-stage press since most new handloaders will have one. A high-quality runout 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 shell-holder 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 one-quarter turn from this setting to prevent cartridge crimping. Next, lower the press ram and remove the case. Place a piece of flat steel 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.

USAMU Handloading Hump Day Seating Die Adjustment Stem TIR Concentricity Run-out

If one were using a 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. Then, secure the stem’s lock nut. Next, load sample cartridges and check them to verify good concentricity.

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 runout gauge will show any effects of changes upon concentricity. However, the first 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.

TIR Study 2: Standard vs. Match Seating Dies

50 rds 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”.

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

AccurateShooter Comment: This shows that, with careful adjustment, the cheaper, standard dies achieved results that were as good (or better) than the more expensive “Match” Dies.

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 22nd, 2018

June Sale on Allliant Powders with $2 per Pound Reward

Alliant powder midsouth Reloder Reloader AR COMP 15 16 17 19 23 sale

If you are looking for popular Alliant powders, now’s a good time to buy. Midsouth Shooters Supply has discounted its inventory of Alliant powders, plus there is a $2 per pound factory rebate. So, for example, the sale price might be $1.50 off regular retail, and then Alliant gives you another $2.00 back for every pound you buy (up to 10 pounds or $20 total rebate). But act soon — this Powder Promotion ends June 30, 2018. Here are some of Midsouth’s current prices on Alliant powders

Alliant Reloder 15 — $26.99 1 lb.
Alliant Reloder 16 — $27.45 1 lb.
Alliant Reloder 17 — $26.99 1 lb.
Alliant Reloder 19 — $26.99 1 lb.
Alliant Reloder 23 — $26.99 1 lb.
Alliant AR Comp — $27.45 1 lb.
Alliant Power Pro Varmint — $25.45 1 lb.
Alliant Power Pro 2000 MR — $25.45 1 lb.
Alliant American Select — $21.99 1 lb.
Alliant Unique — $21.99 1 lb.

Alliant Reloder 16 — Great Powder for Match Cartridges

Alliant Reloder 16 is used now by many top shooters for cartridges that work well with Hodgdon H4350. In fact, we’d say that Reloder 16 is the best substitute for H4350 on the market. Alliant’s RL 16 is very temp stable, offers good velocity, and the accuracy is top tier. Some guys report slightly better accuracy than H4350 in the .284 Win, .260 Rem, 6.5 Creedmoor, 6mm Creedmoor, and 6XC cartridges. If you currently use H4350, you should give Alliant Reloder 16 a try. The powder also boasts excellent lot-to-lot consistency and contains a proprietary de-coppering additive.

This is NOT just a slower version of Alliant’s double-based Reloder 15 (which words great in the 6mmBR and Dasher cartridges). Reloder 16 is a completely new formulation, produced in Sweden by Bofors for Alliant. Reloder 16 utilizes TZ technology, which manipulates the response of the propellant and resists the natural tendency to generate more pressure at higher temperatures and less pressure at lower temperatures. As a result, Reloder 16 offers outstanding temperature stability.

Reloder Reloader 16 Alliant Powder Propellant Bofors TZ temperature stability temp stable H4350

Match and Hunting Cartridge Applications:
Alliant tells us that Reloder 16 “is ideal for traditional hunting cartridges, such as .30-06 Springfield and .270 Winchester, as well as 6.5mm target loads and tactical applications wherein temperature stability is required.” We also think the powder may work very well in these popular match cartridges: 6XC, .243 Win, 6.5×47 Lapua, 6.5 Creedmoor, .260 Rem, .284 Win, and .300 WSM. For example, Alliant’s Load Data Sheet shows a 2772 FPS load with 142gr SMKs in the .260 Rem.

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