September 8th, 2019

Sunday GunDay: 6mm Dasher Winner From Forum Classifieds

Bob A. 6mm Dasher Sacramento F-Class March Madness

With the 6mm Dasher cartridge becoming popular with PRS/NRL competitors as well as the benchrest crowd, we thought it was time to re-visit a special rifle chambered for the 6mm Dasher wildcat. This gun has a great story behind it. Forum member Bob A. (aka “Killshot”) used his “Forum Classifieds Special” to beat all comers in the F-Class Division in the American-Canadian Match and the Long Range Regional Match in 2013 in Sacramento, CA.

Bob’s 6mm Dasher sports a blue-printed Rem 700 action. Who says you need a high-dollar custom action to run with the big dogs? In fact, this same gun, built with components sourced from AccurateShooter Forum Classified Ads, set a Sacramento F-Class range record of 200-17X a few years back. In this story, Bob talks about the build, and he explains his methods for loading ultra-accurate Dasher ammo.

Bob A. 6mm Dasher Sacramento F-Class March Madness

Bob’s Budget-Build Dasher F-Classer
I wanted to build a proper rifle for F-Open but needed to keep it simple and, well, cheap. I found a solid “base” to build on in the form of a Dave Bruno-built, “pre-owned” 6-6.5×47 Lapua that I located in the AccurateShooter Forum classifieds in late 2011. The base action was a trued and blue-printed Remington 700 receiver circa 1971 with a spiral-fluted bolt. It was in a Shehane ST1000 stock painted sky blue and had a Jewell 1.5-oz BR trigger. I sent the bolt to Greg Tannel (Gretanrifles.com) to have the firing pin hole bushed and sleeved, the ejector removed and the hole filled and the face trued. I upgraded to Tannel’s Light Steel firing pin assembly while it was out.

Having the working bits completed, I needed a barrel. So I went to the AccurateShooter classifieds again and found a 1:8″-twist, 30″ x 1.25″ (diam.) Bartlein with a 0.236″-land bore. I called Dave Kiff and explained my pursuit and he recommended his PT&G “world record” 6 Dasher reamer (.2704″ no-turn neck and .104″ freebore). A month or so later the reamer and gauges arrived.

I had the barrel chambered by Marc Soulie of Spartan Precision Rifles (510-755-5293, Concord, CA). Marc is a great builder and I’m pleased to call him a friend.

Bob A. 6mm Dasher Sacramento F-Class March Madness

The rifle got its good looks from a Pennsylvania artist named Kenny Prahl. His Prahl Designs shop (724-478-2538) added the white ghost-flames over the existing sky blue metallic paint.

Looks Great, Shoots Better
Fire-forming showed great promise — ten-shot groups of half an inch at 200 yards were typical. I lost only one case to a split neck and the “blow lengths” are good and consistent. This was followed up with load development which saw 100-yard, five-shot groups in the .1s and .2s as the rifle showed its preference for Reloder 15 over Varget powder, and for CCI 450s over all other primers. The bullet of choice was the ever-popular Berger 105gr Hybrid Target.

Bob A. 6mm Dasher Sacramento F-Class March Madness

In February 2012 I began shooting the Dasher in monthly club matches at the Sacramento Valley Shooting Center, the home range of a number of excellent F-Class, Benchrest and High Power shooters. Using a Farley Coaxial rest up front (also picked up from a WTB ad on AccurateShooter’s Forum) and an Edgewood bag in the back, I gradually improved my gun-handling to the point where I could shoot a respectable score. This was very different from the bipod shooting I’d done in the past in F/TR.

Bob A. 6mm Dasher Sacramento F-Class March Madness


Bob A. 6mm Dasher Sacramento F-Class March MadnessDasher Loading Tips
My chamber is set up for blue box Lapua 6mmBR brass. My case preparation is straight-forward. I fire-form with virgin cases right out of the box. I don’t size them but I will give the primer holes a good look and clean up the flash hole with a .058″ bit in a pin vise. To fire-form, I seat a Berger 108gr BT .030″ into the lands over a standard 6mmBR load of Varget.

For match loads, I use Alliant Reloder 15. While Varget is less sensitive to temp changes, RL15 has given me lower extreme spreads and better long range control. [Bob acknowledges that every barrel is unique, so a different powder, such as H4895 might work better for you.]

I clean my fired cases with stainless steel media in a Thumler’s rotary tumbler after every firing. I anneal after every other firing using a Bench-Source machine which is very well made and easy to operate. I use a Whidden full length bushing die with Redding bushings for sizing.

After sizing, I chamfer the inside of the neck with the K&M tool which has a pilot rod centered in the flash hole. Then I’ll give the neck and mouth a “once over” with some 0000 steel wool. I finish loading off with a Redding Competition Seating Die with the micrometer top.

Bob A. 6mm Dasher Sacramento F-Class March MadnessI use a carbide ball on the expander rod of the full length sizing die. I use a .266″ TiN-coated bushing and the ball just kisses the inside walls of the sized neck. I get very consistent neck tension this way and have had no issue with split necks.

Seating Depth Considerations
With fire-formed brass, the junction of the bullet’s bearing surface and boat-tail is above the neck/shoulder junction of the case, so I have no issues with donuts. You can see how a loaded round looks in the photo at left. For occasional trimming, I use a very nice little Possum Hollow trimmer that indexes on the case shoulder.

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May 21st, 2019

The Honed-Neck FL Sizing Die Option — Alternative to Bushings

Custom honed FL dies non-bushing die Forster

Tired of messing around with neck bushings? Is there a simpler (and potentially better) solution for controlling case neck tension? Yes there is — the precision honed non-bushing die.

You can purchase a Forster non-bushing Full-length sizing die for many popular cartridge types for under $50.00. Then you can send that die to Forster, and Forster will custom-hone the neck for a nominal $12 fee plus return shipping*. When done right, the honed FL die can load ultra-straight ammo with the precise next tension you prefer for your brass and bullet choice.

Alternative to Bushings — Honed Full-Length dies
Conventional, non-bushing full-length sizing dies can create ultra-accurate ammo with very low run-out. For some applications, we prefer a non-bushing FL die over a bushing die — so long as the neck tension is correct. But many FL dies have an undersized neck diameter so you end up with excess neck tension, and you work the brass excessively. Forster offers a simple, inexpensive solution — honing the neck diameter to whatever size you want*.

If you purchase a Forster non-bushing, full-length sizing die, Forster will hone the neck dimension to your specs for $12.00 extra (plus shipping). This way you can have a FL die that provides the right amount of tension for your particular load. (The max amount of diameter change Forster can do is about .008″) Forster dies are relatively inexpensive so you can afford to have a couple of FL dies with necks honed to different diameters — such as 0.266″ and 0.267″ for a no-turn 6mmBR. The die itself is fairly inexpensive — currently Precision Reloading charges $41.49 for a Forster 6mmBR FL sizing die (Forster Part #018121).


Forster FL dies, necks honed to .265″, .266″, and .267″.

Steve Rasmussen of IowaHighPower.com gave this a try. In fact, he had three dies made — each with a different neck dimension. Here’s his report: “My original Forster 6BR FL die sized the necks down a lot [to about 0.260″]. I sent my die in and asked if they could supply two more FL dies (for three total) to have the necks honed to 0.265″, 0.266″, and 0.267″.” In addition to the purchase cost of two more FL-sizing dies, Steve paid $36 ($12 per die) for the three dies to be honed.

Steve’s honed dies produced very straight loaded ammo:
“Brass springback after sizing is running 1 to 1.3 thousandths. My loaded rounds are running 0.2697-0.2699 using [older Gold Box Lapua brass]. So far the dies are working well. I sized 80 cases with the 0.266″ necked die. The shoulder is running 0.4582″ and 0.300″ up from the base is 0.4684". I spun 20 of ‘em and 16 had a runout of one thousandth (0.001) and the other 4 at 1.5 thousandths (0.0015).”

*Here is Forster’s description of its Die Honing Service:

We custom hone the inside neck diameter by using a diamond stoning process. We enlarge the inside diameter to your specification to prevent over-sizing of the case neck due to thick neck walls. You may require this service for multiple reasons: 1) If you use some brands of brass cases which have thicker neck walls. 2) If you do not intend to outside neck turn case necks that have thickened after repeated firings. Please specify desired inside neck diameter. Note: 1) No more than .008″ stock removal from your existing die neck diameter is possible. 2) Honing is done in increments of one half thousandth of an inch (.0005″), meaning that your specified inside diameter must be either.XXX0″ or .XXX5″. FEES: $12.00 plus actual return shipping cost & insurance Please allow 1-3 weeks.

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