LOOKING FOR AN
INEXPENSIVE
PERFORMANCE INCREASE FOR YOUR BARRELS ACCURACY ?
LOOK AT ONE CRYO
There are many things that can be done to that quasi target rifle,
that we commonly call the varmint rifle, to squeeze out that last ounce of potential
accuracy and longevity. Many of these improvements are fairly expensive. Jewel triggers
are an improvement that comes to mind. They are perhaps the best bench rest, target and
varmint triggers available on the market and, once experienced, I guarantee that you would
not like to have a varmint rifle that is not outfitted in such a fashion.
Many of my potential brethren in the varmint sniping business do
not have the resources for this sort of improvement right off and are looking for a
relatively inexpensive group-tightner. One of the many possibilities may be the
deep-freeze. The cost of this process is around 50 dollars, excluding shipping and
handling. This is not an expensive add on!
The wonderful (and patient) people at ‘One Cryo Inc.’,
especially their VP in charge of Sales , Steve Klingbiel in their Orlando facility has
been kind enough to let me explore the process of Cryogenic stress-relieving and how it
relates to the varmint rifle. I say varmint rifle, but the process can carry over to light
barreled hunting rifles, shotguns, and pistols as well. The process is used on many
metallic and non-metallic materials and items that may include ferrous and nonferrous
alloys. The ‘One Cryo Inc.’ brochure states: ‘By treating your tooling,
racing engines’, (an area of heavy use, at the moment, in NASCAR) ‘brake rotors,
gun barrels, and softball bats with our one-time stress relief process, your equipment
will last longer and perform better or your money back.’
I have to admit that I was more than somewhat skeptical about how a
deep-freeze to -300ºF and a triple temper heat treat to +300ºF could benefit my shooting
tools.
With the help of the folks at Remington, I was able to get a
Remington 700 with a heavy stainless fluted barrel, stainless action and synthetic stock
in 220-Swift, in order to do a little investigating. This is perhaps, the consummate non
custom ‘off of the shelf varmint rig.' Toped with a Leupold 6.5-20x40 A.O. scope,
mounted with low extension rings (complements of real business like. I chose the
220-Swift precisely because of its ill deserved reputation for being a ‘barrel
burner’ that was earned back in the 1930’s. It is noteworthy that such renowned
manufacturers as Weatherby had similar problems with barrels and short life, as were
experienced by the Swift shooters back then. Metallurgy was simply not advanced enough to
support the inherent accuracy of the Swift, at 4,000 FPS, for very long. Although
Weatherby gained in popularity, as there problems were solved by technology, the poor
reputation stuck with the Swift.
The truth of the situation is that the Swift is very accurate and
the top performance round of the .224s. What is little known is that some factory loadings
of today in the 22/250 trip out at 4,000 FPS. It is funny that we don’t hear of those
rounds burning out the 22/250 barrels prematurely.
Enough in defense of the round! There will be more of that in
another article.
After receipt of the rifle from Remington, I proceeded with the
barrel break in process, firing over 100 rounds of ammo that was graciously provided by
both Remington and Federal. There was a judicious cleaning between each round.
The rifle produced five shot groups averaging .63 inches in Maximum Spread and .26 in
Average Group Radius (the best performance indicator) at 100 yards. (See; ‘Figure
One’ and ‘Target One’) This performance told me that this rifle was a real
shooter with factory ammo!
I wondered if it was possible to improve on this sort of
performance!
The people at One Cryo Inc. explained that; ‘Our computer
control lowers the temperature of the contents of the processor very gradually, at less
than one degree per minute, until it reaches -300ºF. The temperature is held
here for 24 to 48 hours, allowing the molecules to re-align in a more dimensionally stable
manner where the distance between the molecules becomes more uniform.’ After the
deep-freeze, the material is slowly returned to room temperature and then heated to
+300ºF and allowed to cool to room temp again in three separate one hour cycles.
One Cryo also provided a wealth of literature on the process and its uses in industry, as
well as research on the subject.
The bottom line in this data seems to be that performance in the
areas of dimensional stability and wear resistance of many tool steels and
‘martensitic’ stainless steels (stainless that includes a solid solution of iron
and carbon or the carbide of iron in its structure, by dictionary definition), like 440,
is increased by the process. Most ordinance stainless steels are ‘martinsitic’
400 type steels, as is the Remington, and will be affected by the process. The tool steels
exhibit a more dramatic increase in wear resistance than do the stainless. The gains in
dimensional stability seem almost universal, however.
After receiving the treated barreled action from One Cryo Inc. (You
send them only the barreled action and bolt), it was time to reassemble it. As part of the
reassembly process I was careful to torque the action screws to 40 inch pounds using a
professional torque wrench. This is the top-end torque recommended by Remington for this
action/stock combination that includes the internal aluminum block.
With assembly complete, it was off to the range with this
performance package!
The difference that I discovered in shooting the treated rifle was
significant, but not dramatic. Maximum Spread shrank to .41 inches with an attending drop
of Average Group Radius to .17 inches with Remington Premier® Varmint ammo. (See Target
Two) The Federal Premium 52 grain Sierra Matchking bthp came in a very close second in
this rifle, with group sizes only slightly larger.
I am not suggesting that the Cryo Process is the only possible
explanation for these changes. Certainly, there may be many other reasons, as this was a
‘seat of the pants’ test that was not conducted under controlled
conditions.
What this exercise has definitely shown is that there is little or
no risk of loss of group size, when a barreled action and bolt are treated, and there may
be group benefits along with the attending increase in wearability.
I can honestly say that if I were considering building another rig,
I would send it in for the Cryo Treatment at One Cryo! As it is, Remington is going to
have to do without this rifle in their inventory as I will not give it up easily!
Ballistics data was supplied, courtesy of Recreational Software Inc.
For more information on the deep-freeze, you can reach the folks at
One Cryo Inc. Toll Free.
Thanks to the folks at Remington, Federal, Gander Mountain, the
Detroit Sportsmen’s Congress, and One Cryo, for making this article possible.
Good luck and good shooting!
David Pierce
Editor
American Shooting Magazine
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