Barrel life on 336 ?

Lots of factors play into barrel life. Three biggest areas are Military, Hunting, Varmit shooting, and long range target.

In your example between the AR platform and lever 30-30. The .223 is trying to push a small caliber bullet down the barrel at High velocity with a fast burning powder under High pressure. This is usually done by high rates of fire building up massive amounts of HEAT. All these factors cause faster throat erosion thus resulting in decreased accuracy.

The 30-30 is a much larger projectile usually shot with a slower burning powder with lower pressure. Rates of fire are slower and don't heat the barrel as much therefore throat erosion is much less.

Military, Varmit and Long range target shooters really push the load limits with rates of fire, pressure, fast powders and velocity so their REAL SHORT BARREL LIFE really cant be compared with normal wear.

On average your 300 rounds a year out of your 336 will probley not show any negative affect on accuracy within the expected range of the 30-30 (up to 200 yards) in your lifetime or the next generation.

In general its really the load, combination of bullet, powder that that play into barrel life. A .243 will wear faster than a .223. Pushing a small diamiater bullet behind a Large case, FAST, under higher pressure.

 

I agree with SWO1. With proper cleaning techniques, barrel life shouldn't be a concern. If you're careful not to ding up the muzzle end of the barrel with the cleaning rod, your 336 should preform as designed for a lifetime and then some. Even that can be corrected without replacing the barrel.

 

If you keep it clean and actually wear out the barrel in your lifetime , just get it bored out to the 30 wcf s bigger better brother the 32 spcl .
( I'm not sure if that is possible , just sounded good )
The 35 rem would be a more reasonable re-bore , after , of course you shoot enough to wear out the barrel on your 30 - 30 in the first place

 

Wow I actualy learn things on here lol how can you tell if a barrell is shot out when buying used?

 

Good question......

Actually the Barrel dosnt wear out....Not 98% of it anyway. The two areas that cause problems and result in what is reffered to as wearing out of the barrel is:

1. The Throat. this is the area just ahead of the chamber that the bullet resides in. The brass or casing sits in the chamber and the bullet sits in the throat. Just ahead of the throat the lands start. As the round goes off the bullet leaves the casing and for a short period of time it is suspended in the throat before contacting the lands. This is called "JUMP"

Throats over a period of time become eroaded. Caused mainly by hot gases and particles of unburnt powder. Most prevalent in High velocity rounds (which are under high pressure) and magnified by high rates of fire which build up HEAT. As you heat up metal it becomes softer and more prone to erosion. As a GENERAL RULE calibers LESS prone to throat erosion are slower ammo, I.E. 30-30 for one. Other good ones are 30.06, .308. These are just some. Some of the worst are 220 swift (worst) 22-250, .223, and .243. The .223 is compounded by the AR platform as a lot of folks go Tactical with the 20, 30 round mags and burn thru 100s of rounds in seconds. Erroaded throats cause the bullet to enter the lands "off center". Not good for consistant accuracy.

As for checking used guns there are throat gauges availiable. I would say google them and see whats availiable if you desire getting one.

2. The Crown. This is the last .5" or so of the barrel. When all is right is does nothing. When its not OK....Major problems. Crowns generally have cuts in two angles, 11 deg. (target) and 45 deg. (hunting)

What ever the angle of the cut it should be even all the way around and smooth. As the bullet leaves the barrel the gasses escape behind the bullet evenly and push the bullet in a straight path. If the crown has been damaged and is not flush/smooth/even the gasses will escape off more to one side pushing the bullet in the opposite direction as it exits the barrel resulting in erratic flight paths (crappy groups, missed game). Why are target crowns cut at a shallower angle than hunting crowns you may wonder.... Hunting firearms are subject to rougher handling than the average target firearm and more prone to getting the muzzle whacked...only reason. Also when cleaning, barrels "SHOULD BE CLEANED FROM THE BORE END ONLY". This is easy with a bolt or break open single shot. Not so with an auto or pump without breaking it down. You don't want to bang the cleaning rod handle on the crown. More wear is done on a crown with CLEANING RODS, brushes and jags than shooting. That's why I only use patches.....NEVER BURSHES.

Checking a crown on a used rifle is a visual thing. A good thing is to take a Q-Tip and push it into the end and withdraw it. If it leaves fibers behind in the barrel then there are burrs and signs of a damaged crown. Re-crowning tools are availiable (pretty cheap) at less than $50 and easy to do yourself. To check a rifle by shooting it is to apply White out around the crown and shoot it 2-3 times. Inspect the crown for an even dispersal of powder residue. If there are uneven streaks then it needs re-crowning. Re-crowning can do wonders for an old gun.

 

Again, that's some good stuff. I saw a crowning tool on ebay the other day for $30.00. I might have to check it out and see if it is still there.

 

Thanks, I'm going to have to check that out on my 45 70. On an ar platform was wondering what's the diffrence between a go and no go head spacer?

 

Different type cartridges Head Space in different ways.

Rimmed cases space on the Rim (raised rim) at the base of the brass

Rimless cases space on the front rim of the case

Bottle neck cases space on the neck of the case

Belted cases space on the belt at the base of the case



Head spacing stops the case from going any further into the chamber and allows the bolt, or in the case of a break open action, the face of the action to contact the rear of the case with a standard space. This space prevents the case upon firing from backing out of the chamber and allowing the case to rupture or the primer from blowing out of the primer pocket.

Space Gauges are cartridge like in their design for each caliber and are inserted into the chamber. There are actually 3 gauges, also a Field gauge to carry with you.

The below table illustrates the function of each gauge:
GaugeMeasurementIf Bolt Closes on GaugeIf Bolt Does Not Close on GaugeGoMinimum factory-spec spacing"Go". Headspace is greater than minimum spec."No-Go." Headspace is too short. Bolt will not close on factory-spec cartridges, resulting in jammed brass, and firing out-of-battery, both dangerous conditions.No-GoMaximum factory spec spacing"No-Go." Headspace is greater than the maximum factory spec. Risk of case ruptures if used."Go". Headspace is below maximum factory spec.FieldAbsolute maximum safe spacing.Rifle is unsafe to fire. Headspace is greater than what is considered safe to fire. High risk of case rupture if fired.Generally "go". Headspace is below the maximum for what is considered safe to fire when using factory spec ammunition. Rifle should be evaluated by a gunsmith for possible re-headspacing.
Sets are availaible in popular sizes, also in single.

 

Thanks, I'm on an ar upgrade I guess. I'm switching the standard (stripped) with another one but this one has the dust cover and forward assist on it. Via dpms. The one I'm gonna be using I got from a dif. Manufacturer and I'm concerned with the way it will line up. So I'm assuming a field spacer just for safe messures? And I also have a few tracer rounds and was told on an ar the 1 in 7 barrell is to be used with them not the 1 in9 twist one?