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Old May 4, 2012, 01:42 PM   #1
CraCZ
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life of a barrel?

How long would a barrel last shooting a .311 dia. bullet out of a .308 dia. 16 in. non chrome lined barrel? Say I shoot 250 rnds a month. Sorry I dont know the metalurgy of the barrel but I do know its dead on at 100yds. Also I dont do mag dumps, maybe just a few <grin> I know this is very subjective but what would be your guess? thanks
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Old May 4, 2012, 02:25 PM   #2
44 AMP
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Life of a barrel....

Is determined by many factors. One of them is the owner's requirements. Match shooters/varmint shooters may consider a barrel worn out when groups go from 3/4" to 1inch, for example.

Big game hunters may not consider a barrel worn out until it no longer shoots minute of deer at a given range.

Barrels can be "worn out" (damaged) from excessive, improper cleaning.

What makes a difference in how fast (how many rounds) it takes to wear out a barrel to the point where you are no longer happy with its accuracy is the heat the barrel developes during shooting.

Rapid fire erodes barrels the fastest. High intensity rounds do it faster (fewer rounds) even in slow fire. Overbore cartridges (big powder capacity, small bore size) are the worst, in terms of wear per rounds fired. but everything does it. The difference is in how many rounds it will take before a noticable change occurs.

What wears first is the throat of the barrel. That is where the gas pressure & temp is the highest. I expect a sporting rifle, in a moderate caliber to be good for somewhere in the 5-15,000 rnd range, and more towards the high end, before wear becomes an issue, BUT that is not a given. Again, it dependa more on what your standards are, and how you shoot that will determine how many rounds it will take to get to the unacceptable point.

Specifc make up of the rifle (steel composition, heat treatments, mfg tolerences, etc) also play a significant role, as does the ammo used. Light loads and cast bullets may go 30-40,000 rnds before noticable drop in accuracy. Hyper magnums burning 70-80gr of powder shoving a small bore bullet at the speed of heat might show significant wear in a few thousand rounds.

A moderate round, used rapid fire can cook a barrel long before that same round will do it slow fire.
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Old May 5, 2012, 06:45 AM   #3
CraCZ
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thanks 44 for the response
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Old May 8, 2012, 08:33 AM   #4
tobnpr
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Can't add much to that....

You won't wear out that .308 barrel for years. If you handload, hot loads will wear the throat faster as he said.

Just shoot it, barrels are like tires on a car. You'll need to replace it eventually...
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Old May 8, 2012, 12:24 PM   #5
CraCZ
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thanks tob-In other words "Just dont worry about it"
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