Cryogenics, Barrel Break in, and Accuracy

[ctd12vfan]

Just FYI, I'm posting this is several forums. So this is copy past and if you might find this on other sites. That said though, based on what I saw when scanning this forum and what I've read on this site over the years, I think you guys will be my biggest help.

Alright, after what is starting to feel like a long time and a lot of research, I've decided I need to start actively asking specific questions and get specific answers.

A brief about me, I'm an avid firearms enthusiast, I used to be a professional mechanic, I'm a fabricator and customizer, and a mechanical engineering student, and live in Reno, NV.

So, here is my problem, I have two rifles that I've been having some accuracy trouble with. The first is a savage axis 308. Currently it has a timiney trigger, Devon 10110 bedded stock, a cryoed stainless 26" bull barrel, and clamp on muzzle brake.

The second rifle started as a Battle Born stripped lower, I built this rifle from there. All things being the same, it has a full M16 bolt, accuwedge (for what its worth), and another cryoed stainless 26" bull barrel w/ clamp on muzzle brake, chambered in 223 wylde.

Both barrels were cryoed before the first shot ever even came close to the barrel. I installed both barrels myself, and I am pretty confident that they are correct.

Up until recently both rifles seemed to shoot rather wildly. Just as I would get the groups to tighten up, they would open right back up again. The brand, weight, or type of bullet didn't seem to matter.

More recently the 308 has started to come in pretty tight, but considering this is my 1000yd rifle, its 100yd groups aren't tight enough yet (for me at least). It is the AR that is still giving my trouble. I'm still working on load tests but the consistency just has been there. I thought I finally had it last week but yesterday has proved otherwise. Again, different everything and I can't get a 5 shot group sub moa.

Alright, this part is what is going to start the debates. Does anyone have an idea how many rounds a cryoed barrel takes to break in? The company I had do it, while a great company, doesn't really know.

Now I will say this, I don't buy the whole "break in" process. I think you take it out, shoot it, and then put it away (or clean and put away). That said, I do think that accuracy will improve after some X number of rounds have been fired, typically 50 to 100 rounds, from what I can tell. Research aside, the similar 24" upper on my dads AR did the same thing, we just dialed that in to .5 moa recently. I think we are at about 100 rounds on that one. Both of my rifles are in the 250+ rounds now.

I'm hoping that these barrels are still breaking in and that I need to just keep shooting them. What do you guys think?

Oh, as a note, before my last outing I cleaned the barrels thoroughly and I think they both did worse then the last time, which they did well.

 

[Sully2]

And what do you think the cryo process go for you???

 

[ctd12vfan]

I'm not sure what you are asking. I think it helps in several ways, better heat rejection and increased strength are a couple of them.

The only thing I am really regretting at the moment is that I did not benchmark the barrels accuracy before cryoing. However, I have some other rifles that I am in the process of conducting the before portion of a before and after cryo accuracy test.

 

[shortgrass]

How do they shoot with the clamp-on breaks removed? Sounds to me like your barrels are factory. Some of those can take a long time to "break-in". "Break-in" is not hype when you're talking about barrels that are not lapped. Factory barrels aren't lapped. Ask anyone with a bore scope how nasty (ruff looking) factory barrels can be and how well they can collect bullet jacket. A good custom hand lapped barrel usually only takes a few rounds to remove the "burrs" left from chambering.

 

[ctd12vfan]

That very idea was brought up in another forum. To answer, I can't really say for certain, I will be testing out a couple theories related to what you just said.

 

[Dosh]

CTD, had two factory barrels cryo treated in 2010 since I live near Cryogenics International and couldn't resist giving it a try. I researched this extensively and determined there is no overwhelming consensus on the benefits, only that it can't hurt a barrel. I did not shoot these rifles prior to treatment although they both shoot very well, I can't attribute this to the treatment. I can say these two barrels are easy to clean which again I can't attribute to treatment. I think break in was around 80 rounds. Without a very detailed test result to the positive I will probably not have another barrel treated.

 

[ctd12vfan]

Dosh: You and I are in the same boat. As mentioned that is what I do regret. That said, the company I used has been absolutely incredible. They regularly call me to see what I think about their work. Unfortunately, I have not been able to say anything, positive or negative.

I do plan on getting more barrels treated in the future, however, before I do, I will be benchmarking the rifle thoroughly first.

 

[elkaholic]

From what I understand about cryo, I doubt that it affects break in much. I think the main benefit is settling the molecules so that the barrel harmonics are more consistent and aren't affected as much by temps. Barrel break in, as Shortgrass stated, is pretty much determined by how smooth the bore was to begin with. I don't pretend to be a cryo expert by any stretch, but this is just what I have heard and read.............Rich

 

[ctd12vfan]

From what I understand about cryo, I doubt that it affects break in much. I think the main benefit is settling the molecules so that the barrel harmonics are more consistent and aren't affected as much by temps. Barrel break in, as Shortgrass stated, is pretty much determined by how smooth the bore was to begin with. I don't pretend to be a cryo expert by any stretch, but this is just what I have heard and read.............Rich

As far as I understand it, you are correct about the effects of cryo. My hypothesis about increased break in time is for the increased barrel life. My theory being, if the barrel lasts longer, then break in could also take longer.

What I really need to do is get matching barrels, cryo one, shoot both, and then inspect, destructively if necessary. Of course that is a lot of time, money, and waste of good barrels for a result I'm not certain of yet. Maybe I will do this some day when I have lots of money to burn and am really bored. Until then, I do have a testable theory to my problem and if the accuracy improves with more rounds, then I'll have an idea as to the answer.

 

[Sully2]

CTD, had two factory barrels cryo treated in 2010 since I live near Cryogenics International and couldn't resist giving it a try. I researched this extensively and determined there is no overwhelming consensus on the benefits, only that it can't hurt a barrel. I did not shoot these rifles prior to treatment although they both shoot very well, I can't attribute this to the treatment. I can say these two barrels are easy to clean which again I can't attribute to treatment. I think break in was around 80 rounds. Without a very detailed test result to the positive I will probably not have another barrel treated.

BINGO!....my exact thoughts!!

 

[Garycrow]

Maybe I missed it, but nowhere did you say the maker of the barrels. If they're factory barrels then there's likely your problem. Savage barrels can be decent if you get lucky, but they're nowhere near the quality of a good custom barrel. Looking at the Battle Born website all it says is their barrels are 1-9 twist chrome lined, which means they're likely cheap junk.

I think you're of the mind that the cryo process is going to work some miracle on factory barrels. I think the overwhelming consensus since the cryo fad came around about 15 years ago is that it doesn't do much if anything. I certainly wouldn't spend money to have a factory barrel cryo treated, put that money towards buying good barrels instead.

If you're concerned about barrel life that much then get some good barrels and have them melonite treated. I think far too much is made of barrel life by most shooters, especially those shooting rounds like the .308 and .223 which have extremely long barrel lives already. If you shoot enough rounds of .308 to wear out a top end barrel like a Bartlein or Krieger then you'll have spent many times the amount of money on ammo that you would on the barrel and fitting to start.

All in all, I think your trouble is with junk barrels and has nothing to do with cryo treatment.

 

[ctd12vfan]

Well crap. I had a nice thought out response to Sully2 and Garycrow and then my browser crashed and I lost it. I will have to come back and rewrite it later.

 

[turkn8r1]

Look at PAC NOR or Obermeyer or Bartlein and buy a barrel custom made to your specs. Skip the cryo treatment and see the difference between custom hand lapped 5R rifling, custom twist, custom chamber, screw on muzzle break, 11 degree crown on barrel and brake. It'll run you about $600.00 but you will be amazed and it will be sooooo worth it. Side note. Notice through your research that the top custom barrel makers do not offer cryo treatment nor do they even mention it. Good luck.

 

[ctd12vfan]

The rifle barrels are custom made, not factory. The Axis has a Mcgowen 1:10 and the AR has a White Oak Armament 1:8. Garycrow, you didn't miss it before, I left them out intentionally.

As for the cryo treatment, I understand it is a controversial topic. However, I think that the science behind it is sound. Also, these are an experiment in accuracy. Hindsight being 20/20 I should have mounted and tested these barrels first, that is a correction I am making on the next one.

Garycrow: I do not think the cryo is a cure-all or magic fixer. As for melonite, it is outside my budget at the moment but I plan to use it on some of my rifles too.

I do have a theory I will be testing as to what is causing my problems. Additionally, after reviewing some high speed footage from the other day I will also be looking at one other thing too.

The main intention of this post was not to debate the effects of cryo. It was to get a better idea about barrel break in and accuracy. My thought at the time was that if cryo increases barrel life then it might also mean that it takes longer to break in. I think I mentioned it in the OP, but I do not subscribe to the commonly understood standard of shoot and clean, shoot and clean. I do think that a new barrel does take a few rounds to become accurate.