Gunsmithing CRYO BARRELS the deep freezzz

[mike harper]

Cryo a barrel is this a good thing to do, do we need it or not. Is thier a benefit to de-stressing a barrel with the deep freezzz, and if so who does it. Any gunsmiths want to add to this, all info is good info. I'm sending 3 new barrel to 300Below for Cryo when they get back from Kampfelds (fluting). Price for Cryo $80.00/1, $135/2 & $185.00/3 barrels. What do the smith's say. 300below has been doing this for fourty years, over 50,000 barrels.Yes you can cryo a used barrel. Krieger cryo's there barrel blanks. www.300below.com, 1-800-550-2796.

Thank you

Mike Harper

 

[fnbrowning]

Re: CRYO BARRELS the deep freezzz

Hello Mike;

I think you will get a a lot of pros and cons on this issue.

Others will chime in on their interpretation of the science. But what you're probably wondering is, "does this make sense for me?"

I will tell you that JP Rifles cryos their barrels. I will tell you that I cryo'd my Armalite AR10A4 barrel at 300 Below, and that my AR10 that is not an AR10T and did not come with a MOA guarantee does in fact, shoot <MOA at 100yds. (not discreditable 3-shot groups either, but 5&10 shot groups!) 300 Below web page

This is what I say.
Cryo treating does not hurt your steel. It very well may help. Base your decision on that, and your budget.

 

[buckey]

Re: CRYO BARRELS the deep freezzz

What does 300 Below charge for a barreled action??

 

[Strangedays]

Re: CRYO BARRELS the deep freezzz

I had a DPMS LR-308 went ahead and got the barrel cryod. The gun shot groups of 0.222 at its best (Three five shot groups same load different days) and always was under a half inch regardless with quality ammo. I don't know if I just got lucky or if the croyo made the difference

 

[mike harper]

Re: CRYO BARRELS the deep freezzz

just talkjed to 300 Below, $185.00 for 3 barrels and return shipping and $300.00 insurance per barrel

Thank you

Mike Harper

 

[freerangevoter]

Re: CRYO BARRELS the deep freezzz

I used to cryo aluminum 2-stroke motorcycle cylinders after porting and re-plating the bores. In the handful of before and after dyno tests we did there tended to be about a 3% gain in peak power. I believe this was because the bores stayed rounder.
Cryo is said to have more of an effect on steel than aluminum.

I have not had a rifle barrel cryo'd yet, but it would not surprise me to find that it improves consistency on a barrel that starts the mag cold and then gets hot.

 

[CaptLink]

Re: CRYO BARRELS the deep freezzz

The use of cryogenics treatment is used to the quicken the aging process of austenite into martensite grain structure of hardened steel.Barrels are rarely hardened these days so the process has been questioned if it is of any benefit.
Properly heat stress relieved barrels are probably not as effectively stress relived by cold treatment as poorly heat stress relieved barrels.A re-heat stress relief barrel properly done should be as effectively stress relieved as a cryo treat barrel if preformed properly on non hardened steel barrels.
If you wish to cryo treat your barrel you may do it your self by using a Styrofoam ice chest lined with plastic and covered with K1 kerosine and dry Ice ,temperatures will be below -100F which is enough to transform Austenite into the finer grain marsenite grain structure of hardened steel. I cyro treat after I harden my barrels to attain that ultimate wear that a heat treated barrel can have "Gunsmith at Large"

 

[Five7guy]

Re: CRYO BARRELS the deep freezzz

Heres my $.02... I dont have any rifles with cryo barrels but I do have a Benelli Supersport shotgun with a cryoed barrel and chokes and its the best shooting shotgun Ive ever ownered or shot. So as previously stated I dont think that you are wrong having it done personally I dunno if I will do it to a barrel just because of the cost involved but I think that there are definite benefits.

 

[leagle2]

Re: CRYO BARRELS the deep freezzz

Is there any benefit to doing it twice. Once before chambering and again after chambering? If not, from an accuracy standpoint (if there is one) is it better to do it before or after chambering?

 

[427Cobra]

Re: CRYO BARRELS the deep freezzz

Good Question leagle, plus what if I want to Melonite a barrel, cryo it first or after

 

[mtang45]

Re: CRYO BARRELS the deep freezzz

Can used barrels be cryo'd? It would be interesting to do a before and after comparison.

 

[Gene Poole]

Re: CRYO BARRELS the deep freezzz

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: P.A.R.</div><div class="ubbcode-body">The use of cryogenics treatment is used to the quicken the aging process of austenite into martensite grain structure of hardened steel.Barrels are rarely hardened these days so the process has been questioned if it is of any benefit.
Properly heat stress relieved barrels are probably not as effectively stress relived by cold treatment as poorly heat stress relieved barrels.A re-heat stress relief barrel properly done should be as effectively stress relieved as a cryo treat barrel if preformed properly on non hardened steel barrels.
If you wish to cryo treat your barrel you may do it your self by using a Styrofoam ice chest lined with plastic and covered with K1 kerosine and dry Ice ,temperatures will be below -100F which is enough to transform Austenite into the finer grain marsenite grain structure of hardened steel. I cyro treat after I harden my barrels to attain that ultimate wear that a heat treated barrel can have "Gunsmith at Large" </div></div>

Very interesting. We used to use dry-ice/acetone baths in the lab to get temperatures as low as -78C (-108F), the temperature that dry-ice sublimes at atmospheric pressure, so the kerosene method seems sound. There were other solvents/salts we'd add to get a specific temperature depending on the reaction we were trying to do.

You're description of the grain conversion at those temperature is interesting, but it seems to me you'd want to do this on the barrel stock before you did any cutting on it to get the max benefits from this.

 

[Alabama556]

Re: CRYO BARRELS the deep freezzz

I wonder how it would effect a complete barreled action to be cryo'ed? I have 2 guns built by gunsmiths who swear by it and they both shoot lights out. I bet the process works better for button riffled barrels than for cut rifled barrels. I am going to send a few rifles out and see what happens.

 

[mike harper]

Re: CRYO BARRELS the deep freezzz

300below uses a dry cryo process, rather than a wet process. Yes you can cryo a used barrel.300below has been doing this for 40 years,50,000 barrels.

 

[Geno C.]

Re: CRYO BARRELS the deep freezzz

I know one of the VERY well respected barrel makers on this site and they cryo their stock before rifling. He told me that the tooling lasts longer ever since they started doing it. I would ask your barrel maker if it was already treated.

 

[apricot]

Re: CRYO BARRELS the deep freezzz

every gun i own has been cryoed. easier to clean,shoots better, and lasts longer. been doing this for years. along with proper break in and cleaning. money well spent!

 

[perazzisc3]

Re: CRYO BARRELS the deep freezzz

does it make any sense to cryo a barrel that has been shot?

 

[cmh2007]

Re: CRYO BARRELS the deep freezzz

I wonder if it would make my shotout .308 shoot better

 

[Mike Casselton]

Re: CRYO BARRELS the deep freezzz

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: perazzisc3</div><div class="ubbcode-body">does it make any sense to cryo a barrel that has been shot? </div></div>

I did load development for a buddy that had a Rem 280 Mountain rifle. The gun shot right at 1/2" with most loads. Cleaning it was a bitch.

He asked me to get it cryo'd before he got back home from deployment. Got the cryo done, reshot the loads (no change)and cleaned it up before I gave it back to him. The cleaning after cryo was basically a few wet patches followed by some dry ones. The barrel no longer required a 1/2 hour of scrubbing to get it clean.

The cleaning ease was worth the money in my opinion.

 

[dunes450r]

Re: CRYO BARRELS the deep freezzz

i've heard both good and bad about cryo, but haven't ever tried it myself

 

[jake6547]

Re: CRYO BARRELS the deep freezzz

I talked to gary schneider on the phone he says that the type of stainless he uses doesn't need to be cryo'd.

 

[Ring]

Re: CRYO BARRELS the deep freezzz

ive never seen anything bad from it.. just not sure ive seen good... i had a savage done in the early 90's.. cost me like 50$ at the time, since 300 below is not a far drive for me...

all me new guns i nitride...

 

[Nocalphoenix]

Re: CRYO BARRELS the deep freezzz

Talking to a lot of non-gunsmithing machinist they like all of the parts cryo treated if possible. They claim significantly better tool life, cleaner cutting and more precision. I dont know squat about machinging so I have to take their word for it. If it matters they are all working at a nuclear research lab.

 

[Run N Gun]

Re: CRYO BARRELS the deep freezzz

If you talk to a lot of guys shooting hunter class they quite doing that a couple of years ago. it didn't extend their barrel life and just added cost

 

[HPLLC]

Re: CRYO BARRELS the deep freezzz

It seems that the largest problem with learning anything about Cryo are the number of people who will comment without any experience.

I cryoed a barrel on a M70 once that had been shooting 1.3-1.5MOA , but I also had the barrel lapped and action bedded in the same trip to the gunsmith. My stock was HS precision with the aluminum block so bedding should not have been too terribly important.

My gun shot .3MOA with the same ammo after the work. I'm sending another barrel this week to see what happens with it.

It sounds like good barrels may not benefit other than increased POI consistency (which is still a benefit), and bad barrels probably will benefit.

If your barrel is sub 1/2MOA, I would not cryo. The barrel I'm sending currently is consistently ~1.3MOA for 3 and POI wanders making a 23 round group 2.5MOA.

 

[rkgsmith]

Re: CRYO BARRELS the deep freezzz

I've never done a rifle, however years ago we shot a lot of 3 gun matches. On slug stages with 15+ rounds the slugs always started to string out vertically once 4 or 5 rounds were shot. (with optics on the receiver) After a few rounds the shots would walk right off the target. Sent the barrels to 300 below and after that 20 rounds straight at 50 yards in the A zone. I'm a believer.

 

[LRI]

Re: CRYO BARRELS the deep freezzz

After machining/fitting probably well over a thousand barrels in 13 years I can tell you that when Kreiger went to the cryo process it made a remarkable difference in the surface finish of the steel. Both chambers and threads.

The only two that come close/same are Mark Chanlynn barrels and the Bartleins we've been doing a mess of (9 of em today alone in fact) lately.

Whether it makes it shoot better or not will probably never be fully resolved as there's so many variables involved that it would be very expensive to conclusively sort out.

I do know that it helps make bright shiny surface finishes though.

FWIW if I understand the process correctly, you'd want the steel stress relieved PRIOR to performing any machine ops that bring the part to final tolerance. (meaning before you ream, put in the wrinkles, lap, and contour)

Stress relieving a part like a barrel after all the work is done seems to me to be a risky endeavor. Alter the bore dimensions due to material pushing around and there's a very real possibility it won't shoot as well as it did.

Who knows?