Is this what I should expect?

[Rich Coyle]

After 530 rounds I measured the overall length again. The overall lingth has increased .220". Is that about right for this amount of shooting.

The cartridge is a 338 RUM neck down to 7 mm using 7 RUM brass to gain a .100" longer neck. The load is 87 grains of H4831 was was the hammer Hunter 131 and hammer hunter tipped 132 grain.

 

[Varmint Hunter]

That sounds extreme to me but my first 22-250 had about 2" of rifling gone by the time I rebarreled the rife. The odd thing was that it still shot acceptably with longer/heavier bullets.

 

[lancetkenyon]

That is a LOT of heat, friction, powder scortch/flame, and velocity wreaking havoc on that throat. .220" doesn't sound out of the question. A hot 28 Nosler has barrel life of 400-600 rounds. You are right there.

Top fuel dragsters don't last long. Neither does a rifle that has to be pushing somewhere near 3600fps.

 

[jessej]

That's purt neer a qtr inch

 

[Rich Coyle]

lance,

Velocity averages 3,665 feet per second with 132 HHT. I tried some 90 HH at 4,290 feet per second, but they didn't

 

[Rich Coyle]

Group well at 300 yards.

 

[44-40]

Yes, that is about right...lots of powder down a smaller bore, just erodes barrels. I felt that the Stainless Steel barrel to erode faster than regular CM steel barrels. And hammer forged machinesgun steel and hammer forged in general will out last SS in pulled or cut rifling, that many of us use as the cut rifling seems to have an accuracy edge in stainless steel. Stainless barrel steel is easier to machine, than hamer forged and CM steel, and get good finishes. I just rechambered an old hammer forged barrel, with 8000 308 Win rds on it, and reprofiled it for AR 15 project. A little fire cracking is still left in the throat, but the rest of the barrel is nice and smooth...it was free, and good for experimental purposes, and it was still accurate after 8000 rds. Can't prove any of those observations, but it's just what I observed over the years of shooting and chambering different barrels. If ya want to shoot many thousands of rds with accuracy with one barrel get a 308 Win.
High Performance cost, like a race car... a few runs, and it's time to rebuild.

 

[yobuck]

Barrels will last a lifetime or more if just used for LR hunting and a few practice rounds each year.
Im still using a 50 + year old barrel chambered in 300 Wetherby necked down to 7 mm.
I have pushed it to close to 3500 with the 162 gr Hornady match bullet.
But my normal load is about 3350.
BUT, we dont use the hunting guns for rock shooting.
A 308 is all you really need for that, and again it will last a lifetime.

 

[mullmann03]

As Eric Cortina said don't chase the lands.Hot rods are going to erode quickly. This is my .243 that was barreled in 1996ish. It has a lot of rounds down it. I have not measured it recently, but this OAL is from a few years back when I started loading for it. I'm sure if I measured I could push the bullet out farther. Still shoots well. I don't put a lot of rounds thru the big cartridges so I don't have to worry about going thru barrels.

 

[trout004]

For comparison, my 7mm rem mag pushing 175's and h1000 at 2920 fps grew .024" over 415 rounds.

 

[K.E.C. Darkside]

Your right on track. The 7RUM and 28 Nosler will give you 5 to 600 rounds, and you will need to start thinking about a new barrel. I'm going to rebarrel one of my 7RUM next year, I ordered a 277/7RUM reamer for it. It will become a bonafide Barrel Burner, maybe 500 rounds. You have to Pay to Play.

 

[Joefrazell]

Does is still shoot?

 

[WeiserBucks]

I've got a 7 RUM being built right now, I fully intend to kill the barrel in 500 rounds w/ N570.

 

[Rich Coyle]

The last five three shot groups I fired at 300 yards:

11/16", 1 3/8", 15/16", 2 1/2", and 1" in that order.

I liked every shot as it broke. So, it sure appears it is a 1 MOA rifle. My longest shot on a deer is 300 yards and for a elk was 400. Therefore, it will be good for another season.:)