The companies doing this promise:
-tighter groups
-easier, less frequent cleaning
-longer barrel life
-more velocity

What is your experience?
Do you think it worthwhile on a Sako 7mm mag hunting rifle that now shoots about 1.5" average?

Well, I never found that it made any difference at all. Normally when I get a barrel for install and it's a regular customer and if I have time, I will put the barrel on centers in the lathe and zero a 1/10th indicator on it and warm it up with a propane torch. I have had a few barrels that I could run on centers and warm up that would walk over a few thousandths after heating and I sent some of them out for cryo treatment. They wandered the same after thay came back.

a bumm barrel is a bum barrel - freezing it isn't going to do anything

Complete hype and nonsense. Don't waste your money. It takes heat to stress relieve a barrel.
Clean and maybe lap your 7mm,, check bedding, etc.

The time to cryo a barrel is after rifling and contouring and before cutting the chamber. The rest is marketing hype.

But you will find a lot of the high end barrel manufacturers do it before chambering. It does relieve stress and the metallurgical science is quite sound. But there is a whole lot of additional engineering/science required to make a firearm accurate.

Thanks for the responses. This rifle belongs to a friend who is complaining about accuracy, and saying that he's getting vertical stringing. Someone has suggested cryo treatment to him. Yes, I've given the rifle and the scope a very thorough inspection, including borescoping, and made a couple of corrections. I cannot replicate the vertical. I have no idea how good his bench set-up and technique might (or might not) be.

Even if the treatment shrank the group a little, I see no significant advantage. Deer and elk at 200 yards are pretty big targets.

I do appreciate learning your real experiences.
Brice

On good quality and new barrels it has no mesurable effect. I ran a test of a barrel batch of 100 barrels that was from same batch, in same caliber, and later installed on identical actions.
They were sorted in 2 batches, 1 left, 1 right 1 left and so on.
The one batch was cryo treated the other not.
After final asenbly of the 2 batces we tested with same lot of ammo. fiering 5 rd Groups.
Ther vas no difference in the avarage groupsize.

But on well used barresl that has lost accuracy, cryo seems to Work, in several cases resulting in Group sizes shrinking up to 60%.
My guestimate is that cryo mighr remove powder glasing, because of the difference in thermal ekspantion betwen steel and powder glasing.
It seems that fouling and glasing sort of pops of, leaving a werry clean bore.

I have done a lot of cryo barrels. I have had the unmachined blanks done, drilled and rifled blanks done, and after all machine work was done. Most of the cryo companies do not have equip. to do a true cryo. You might as well throw them in you wife's freezer. I think(I think) that it machines easier, but I wouldn't say better. I don't believe it stress relieves the metal.
I believe one of our most respected barrel makers no longer cryo.
SNAKE OIL!!

Interesting link: http://www.epsovens.com/heat-t...eat-treat-furnace/13

It does seem hard to believe cooling, which prohibits movement of carbon atoms outside the iron matrix, can induce stress relief. It seems like it would just lock in the current state.

Cryoing doesn't stress relieve a barrel

the cryo companies are BSing you into buy the service.

What it does the short version is it increases hardness and strength but usually at the cost of toughness, and if you don't know what all those terms mean you need to do some home work on metallurgy,

Cryo treating tool steels has been going one for a few decades and I'd say only in the last two decades has it taken hold in the gun industry. There is good solid science and research behind the process and it is very limited in what it will do

All four points posted by the OP are complete BS

What will happen is the material will be slightly harder and stronger which can make it machine a little more forgiving in terms of deformation and surface finish. outside of that you will never see a bit of difference on paper that you shoot.

I hate to admit this. I sent a pre 64 Win 70 257 Roberts target model barrel to be cyro'd way back in the early 90's from a magazine article. The barrel came back purple; it was a nice original blue when I sent it in! Ouch, talk about accidentally runining a valuable gun!!!