l have shot about 1000 round out of my 7mm rem mag and the accuracy is still fine. l ownly use federal power-shock soft points(150grains) and lately l have been useing federal power-shock soft point 175 grains. l have heard all sorts of things about barrel life. l was wondering how many rounds does it take to notice a dramatic change in accuracy? l dont care about small changes in accuracy as l dont target shoot. so my question is: how many round does it take the 7mm rem mag to not be able to hunt at 500 yards any more???
I am interested also in barrel life. I was told when you start pushing the 3000 fps speed the barrel life shortens no matter the caliber. I hope that some more experienced target shooters help us here as I am a hunter also and don't shoot a lot at one time unless it is a prairie dogs.
Every man needs a good woman, good dog, good horse and a good gun.
My factory 7mm Savage has over 2000 rounds down the tube. I have not babied it either. Many times I have engaged multiple targets till you wouldn't want to grab the barrel. Over 90% of these were loaded with 162gr SST and a max safe load of H1000. It was a solid 1/4 MOA shooter and now will still do 1/2-3/4 MOA, so I'm still happy with it. It will probably get another 7mag barrel when I call the ball on this one.
Barrel life is a loaded question for any cartridge, since it means drastically different things to different communities. for LR target shooters, somewhere in the 1,000 vicinity is pretty good barrel life from this cartridge, and I'd say most would have retired the barrel at least a couple hundred rounds ago. For hunters, you've likely got another 1,000 rounds or more to go before you'd need to begin worrying about it. If you're focused on strictly LR hunting, as opposed to the more run of the mill "normal" hunting ranges, then you're (again) probably at the limit right now. It all depends. Not trying to dodge the question here, but there's variables involved here depending on what the rifle's being used for.
The very first thing to understand is how a barrel goes bad. I've never seen one that hit a certian round count and then just quit shooting; doesn't work that way. Barrels that are completely shot out can still shoot very good groups, they just become less consistent in doing so. And that's what makes it difficult. If you have a barrel that will consistently shoot 1/2 MOA (random figure here) with 10-round groups, that barrel should do that each and every time that load is used. As a barrel begins to wear, you'll start getting flyers that fall from the group. In some cases it may not amount to much, but a round, or maybe two, will impact outside that group. It may not be too far outside the group, but it is a flyer. Many shooters see this and simply disregard them, assuming maybe they fired a bad shot, the wind caught them, whatever. As you continue to use that barrel, those flyers will continue to increase both in frequency and distance from the centroid of the group, until the shooter finally comes to the realization that he didn't fire a bad shot, and the barrel may be going south. The problem is, many of the shots will continue to go into the center of the group. If you're using smaller group numbers, say five, or even three round groups, this problem becomes even harder to spot. I'd hazard a guess that many of the barrels that shooters identify as being shot out, were actually "shot out" long before they made that realization. I've shot out hundreds of barrels ove the years, and don't believe I've ever seen a single one that just quit shooting at a certain round count. It's a gradual process, and it takes time to identify it, isolate it and confirm that that is indeed the problem.
I do some NRA Highpower shooting - mostly the prone matches.
Often I'll notice that a good barrel will still be shooting good scores as the round count mounts, but eventually I'm getting fewer and fewer X-ring hits out at 600 yards. Hmmm... Might be me, I'm certainly not a perfect shooter, but... Usually that's time for me to re-barrel.
A gunsmith with a good bore-scope can get you a look at the throat erosion on your barrel. It's quite an education seeing what was all nicely polished now looking like alligator skin. With the naked eye it can appear a bit "grayish" or almost smokey looking inside the barrel, in the throat area.
Point has already been made that barrel life is very much dependent on your standards - what you will accept for accuracy. If you insist on 1/2 MOA, well, you may well already be well past that. If one MOA accuracy is your goal, you're likely okay for quite a while.
Frankly, for big game, a one MOA rifle will do quite nicely out at 400 - 500 yards, if the hunter/shooter is up to placing the shot well in the first place.
Barrels are like tires - even the good ones wear out eventually. Take it as an opportunity for a serious upgrade to your rifle, and a chance to try something from Krieger, Broughton, Lilja, Hart or whatever is your poison.
I totally agree with Kevin on this one. The only experience I have with a shot out barrel was in fact a 7mmRemMag Sendero. It developed just as Kevin describes.
The 7mag I had, shot absolutely great, one hole, literally, for most of its life. When I first got the rifle I tried 120/130 and 140gn bullets before settling with the 150's. I shot the 150gn Ballistic Tip @ 3100+fps for everything after this. About the same time that I noticied a roughness in the bore (first 9-12 inches) is also when I started getting unexplained fliers. A couple were actually at unalarmed deer, 300yds or less and from a solid rest. When I would check the zero afterwards, the accuracy was still sub 1/2", but it would take a couple of hours just to get the copper out of the barrel. This rifle had been a solid performer but I lost confidence in it and traded it. Round count was about 12-1300 when I divorced my rifle. :(