Page 59 - American Rifleman (February 2020)

5.

4. 8. 9.

e carbon-
e carbon-

ess
ess
ber/stainl
ber/stainl
d th
eta
eta
d been d
d been d
ch
ed an
d th
ch
ed an
muzzle brake installed, but my rst-gen ri e shipped only
ed, but m
y
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ed, but m
y

stall
uzzl
e br
m m
uzzl
e br
e in
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ak
ak
el ha
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barrel had been detached and the carbon- ber/stainless muzzle brake installed, but my rst-gen ri e shipped only rst-gen ri e shipped only rst-gen ri e shipped only
barr
barr
steel substitute had been placed, it was time to determine with a thread protector in place. As the more-than-satis ed

proper headspacing of the new chamber prior to cranking owner of a Dead Air Sandman-S suppressor who had recently
the nut tight. I reached out to Forster Products for both a removed the company’s Keymount Muzzle Brake
“Go” and “No-Go” gauge (7., forsterproducts.com, $36 each) (9., deadairsilencers.com, $90) from another ri e, I felt

for the ri e’s 6.5 mm Creedmoor cartridge. Once the optimum that the newly renovated Ruger would make a perfect silencer

measurement had been reached, one that would not allow host. Not only is the three-chamber Keymount an effec-
the action to close on the “No-Go” gauge but that permitted tive muzzle brake in its own right, but its presence allows
hassle-free bolt throw with the “Go” gauge chambered, the for one-handed installation of my can—and, in my opinion,

barrel nut was tightened and locked in place, and I moved the quickest way to upgrade any rearm is to suppress it. The
my attention on to the fore-end. Creedmoor is not a harsh-recoiling cartridge to begin with, and
A rst-run model, my RPR came from the company with the Keymount, either with or without the attendant suppres-

a round, free- oating Samson Evolution handguard with sor, cuts down felt recoil through this sizeable ri e dramati-

KeyMod slots at the 3-, 6- and 9-o’clock positions and a full- cally; the scope’s crosshairs never leave the target.
length Picatinny rail running along the top. Ruger quickly With the makeover complete, it was time to venture to the
abandoned this fore-end in favor of an M-Lok-compatible range to see just how well everything performed together. But
model with no Pic rail, and by substituting in the Catalyst before I started a formal accuracy evaluation, the necessary but
Arms Fast Track (8., catalystarms.com, $220) onto my tedious task of seasoning the barrel had to be slogged through.
personal gun, I have done essentially the same thing. For optimal performance of its barrel, Helix 6 Precision has
Omitting the 12-o’clock rail considerably increases scope developed a recommended break-in procedure that burnishes
clearance, and, in addition to M-Lok on both sides and the throat/leade area of the chamber before copper and carbon
the bottom surface, a 1.5" dovetail has been cut into fouling have the opportunity to deposit themselves there. It
the 6-o’clock face to provide Arca-Swiss-mount compat- essentially requires re-cleaning with copper-solvent-soaked
ibility. In addition to short-action RPRs, the Fast Track’s patches and bronze brushes after every three shots for the rst

dual-barrel-nut design also accommodates AR-15s with 50 or so rounds of ammunition red through the tube. And

low-pro le gas blocks. despite my general impatience when it comes to things stand-
Finally, with the new barrel and handguard in place, all ing between me and shooting, over the course of about four
that was left for the assembly phase was to nd an appropri- hours, I did follow the company’s guidance to the letter.

ate muzzle device. Latter-day RPRs come from Ruger with a continued on p. 74
SHOOTING RESULTS (100 YDS.) PERSONALIZED RPR
Once the new
carbon- ber 6.5 MM CREEDMOOR VEL. @ 15' ENERGY GROUP SIZE (INCHES)
barrel was in CARTRIDGE (F.P.S.) (FT.-LBS.) SMALLEST LARGEST AVERAGE
place, “Go” and REMINGTON PM 2707 AVG. 2,278 0.44 0.68 0.53
“No-Go” gauges 140-GR. OTM 12 SD
from Forster SIG SAUER EMG 2744 AVG. 2,340 0.58 0.76 0.67
Products 140-GR. OTM 11 SD
were used to WINCHESTER MATCH 2667 AVG. 2,211 0.42 0.88 0.65
con rm proper 140-GR. BTHP 8 SD
headspace. AVERAGE EXTREME SPREAD 0.62
NOTES: MEASURED AVERAGE VELOCITY FOR 10 SHOTS OVER AN OEHLER 36 CHRONOGRAPH
AT 15 FT. ACCURACY RESULTS FOR FIVE CONSECUTIVE, FIVE-SHOT GROUPS AT 100 YDS.
FROM A CALDWELL REST. TEMPERATURE: 80° F. HUMIDITY: 14%. ABBREVIATIONS: BTHP
(BOAT-TAIL HOLLOW POINT), EMG (ELITE MATCH GRADE), OTM (OPEN-TIP MATCH),
7. PM (PREMIER MATCH), SD (STANDARD DEVIATION).
57
AMERICANRIFLEMAN.ORG FEBRUARY 2020