can it be done? what can i expect to gain on my 338 wm? how much can i expect to pay for it?

You will gain a great deal of painful noise that you will pay with both your hearing, and those around you.
I was walking up a trail one day with a buddy walking behind me. He spotted a mule deer on the top of the ridge, and shot (he missed). His muzzle was level with my ear and maybe 4 feet distant, but pointed about 60 degrees away. He was a little afraid of the recoil of his 7mm RM, had a muzzle brake installed. It was painful, and I couldn't hear anything for a while. He was never invited back to the elk camp after that day.

Yes, brakes can be installed. Depending on what you want, and if you're looking threaded or not, you might be looking at $75 thread job, then anywhere from $50 to $300 for a certain brake.

Yes, it will be louder at the shooters position depending upon what brake design you get. High quality breaks can bring that 338wm down below 300wm/.30-06 recoil levels, some even lower. A good radial brake will cut down your recoil a lot. If you're wanting something to reduce hop too, get one of the "gill" types instead (not as effective at total recoil reduction in my opinion, but good at hop!)

I can't say from a performance standpoint what you might gain, but you WILL gain alot of noise.

I had a "break" installed on one of my rifles that recoiled like a mule and made the rifle unpleasant to shoot...so much so I couldn't shoot it accurately...but I loved the rifle. After the break was installed the rifle became pleasant to shoot and now accurate because I could do my job...it cost me a total of $200 15 years ago but I also bought the top of the line break...I'd do it again in a heartbeat. Increased "noise" is a non-issue as I always wear hearing protection like I should. I also recently bought a Savage Model 10 FLCP-K and it has a factory break...again, love it!

Never could understand buying that big a cannon that you need to start adding something like that to be able to shoot it!!!

Brakes aren't just for big bores. Any cartridge with substantial recoil can benefit from a break. I have a gill type on one of my AR's, a radial circular hole type on a .22lr that I use for longer range work, my wife runs one on her .284win.

No reason not to reduce recoil. The only downside is report volume at the shooting position. Wear hearing protection-problem solved.

If you're going to cast stones at muzzle brakes, there better be nothing but steel buttplates in your safe. A muzzle brake ain't anything but a recoil pad that goes on the wrong end of your rifle.

"If you're going to cast stones at muzzle brakes, there better be nothing but steel buttplates in your safe. A muzzle brake ain't anything but a recoil pad that goes on the wrong end of your rifle."

Ya got me on that one, LOL!!! Actually though, I think I do only have a couple that have soft buttplates. Interesting to hear RR on his use of them and that makes a lot of sense!

Yeah they certainly have value like RR pointed out...but after seeing my buddy shoot with one on his .300wby, no way would I want the added noise. I was behind him a good ways and just curious as to how loud it would be, so I didn't plug my ears. My ears rung like I shot a .44 with no muffs....it was horrible. I couldn't imagine shooting that thing a couple times in the woods.

In a hunting situation (for me) I would never wear ear protection, so I personally would rather deal with recoil than noise.

Not a fan of breaks.

I am a fan of good shooting form.

Also recommend both ear plugs and muffs when practicing (best aid to provent developing a flinch).

In the field I never use hearing protection.