Shooters Forum banner

161 - 180 of 206 Posts

·
Registered
Joined
·
6,190 Posts
DDL,

Barrel life is usually limited by throat wear. How badly the throat wears depends on how much heat it is exposed to for how long. The steel damage is actually due to differential temperature expansion between the bore surface and the steel substrate. Every time it goes through a heating and cooling cycle, the surface steel fatigues and weakens. Eventually that leads to the alligator skin cracking pattern you see in a worn rifle throat. The surface attachment of the individual alligator squares to the substrate continues to weaken with further firing, and eventually it gets weak enough that a passing bullet cracks it loose and the propellant gas pushes it out of the muzzle. So it flakes off, leaving the throat uneven and resulting in poor accuracy.

In the 6.5-284, the case water capacity is 20% higher than in the 6.5×55, which gets normal high power barrel life. The slow powders used for the .284 case will sustain the heat longer, which multiplies the 20% energy addition still further.

The speed of the bullet does not directly determine the effect. The 16" battleship guns in WWII, firing at about 2500 ft/s, lasted about 400 rounds, IIRC. That's just .308 Winchester velocity, but they release a lot of heat energy. I suspect that because most well-known barrel burners are overbore rifles loaded to impressive velocities, that it leaves the mistaken impression that high velocity is required to burn barrels up.

Military "308" is supposed to be 2800 fps (usually not) and M118 is 2550 out of 7.62 chambers.

Add to that one how bad it is for people that love to rapid fire. On average a good USGI NM barrel was good for 7,000 rounds or more depending. I usually shot matches, but take it out and shoot a practical rifle match... it cuts the bore life. Moderate matchs like High Power weren't that abusive. Rattle battle... oh the pain! (and why ARs do so well these days).
 

·
Registered
Joined
·
686 Posts
I just bought a new 7mm RemMag and 8 pounds of 7828. Looks like the powder will last longer than the barrel.
 

·
Registered
Joined
·
6,190 Posts
interesting you say to clean my rifles when accuacy tails off. i always thought i should clean my rifle after every session at the range no matter if i shot 5 or 50 shots? am i wrong in doing this? does doing that constitute improper cleaning? what exactly is impoper cleaning?
If you're shooting jacketed bullets, cleaning your rifle after a day at the range is a good habit to stay in. Cast is another issue.

As far as long term storage... I use Break Free collectors, but have had a friend that stored his with a dehumidifier running 24/7, but didn't pay attention to the dust and dirt building on some rifles and ended up with rust. It draws moisture out of the air better than any dehumidifier. If you run a patch with anything down the bore, dry patch before heading to the range.

Normally I check on a rifle every 30 days regardless. But I'm old school
 

·
Registered
Joined
·
367 Posts
I usually clean my rifles the day I shoot them, but I came across and article somewhere (I tried to find it again to no avail) that said that leaving a little powder fouling in the bore could protect it from rust - in other words, don't worry too much about cleaning your gun right away. Obviously he was talking about modern smokeless powder with non-corrosive priming and not black powder, but have any of you heard of any such thing? I also know that improper cleaning has damaged more barrels that shooting, but I don't think I ever remember my dad ever cleaning his guns? While living at home I took over that chore mostly without him ever knowing.
 

·
Registered
Joined
·
6 Posts
Accurate Ordnance built my .308 rifle. When I asked Mark, with their company, how often to clean the bore and what my expected barrel life would be, he said, and I quote, "Only clean the barrel when the groups open up and you should expect total awesomeness out of the barrel for between 6k and 8k rounds." Accurate Ordnance uses, and Mark recommended the KG products as they don't contain any ammonia and won't harm the barrel chemically. Accurate Ordnance builds a rifle that is second to none in accuracy and all of their employees are shooters - most compete. If anyone should know how to treat a barrel, it's the guys who make the rifles and provide a guarantee and warranty for that rifle. I think I'm going to follow their advice. For the record, Accurate Ordnance is not the only manufacturer of precision rifles that recommends only cleaning when the rifle tells you to by opening up its groups. GAP and others say the same. Barrels shoot better with the right amount of fouling. Clean when fouling has accumulated to the point it's affecting accuracy. I clean the action and exterior of the rifle as they need it. This is the cleanest running rifle I've ever owned.

Accurate Ordnance .308 - Bartlein M24 contour finished at 24" w/Fat Bastard brake - Defiance Deviant short action - AICS AT chassis - Schmidt and Bender PMII 5-25x56 P4f reticle - Atlas Bipod.
 

·
Registered
Joined
·
168 Posts
Depending on accuracy criteria, the average barrel can be replaced as early 1200-1500 rds, or, if a less
stringent criteria is applied, 2500-3000 rds. There are barrel burners though, such as the 264 Win Mag, the 6,5x284 Norma and the 26 Nosler (barrel burned up and had to be replaced after 500 rds).

From a practical POV, most hunters will never burn up the barrels of their favorite hunting rifles.

The reasons for replacing a barrel are more than simply that the barrel is burned out! I've replaced several barrels on my rifles, only one had been shot out. I have had "bad" barrels from several mfrs. To me, "Bad" means poor accuracy, excessive fouling, warped, and just simply too slow. Replacing the barrel
usually corrects whatever the problem was and restores the rifle to producing the full capabilities of the cartridge it is chambered for.
 

·
Registered
Joined
·
6,190 Posts
Depending on accuracy criteria, the average barrel can be replaced as early 1200-1500 rds, or, if a less stringent criteria is applied, 2500-3000 rds. There are barrel burners though, such as the 264 Win Mag, the 6,5x284 Norma and the 26 Nosler (barrel burned up and had to be replaced after 500 rds).
Whew... with some care and wise use of the rifle, I used to get 7-8000 out of my M14 NM barrels. But I wasn't inclined to rapid rifle without good reason and I have never pushed for radical velocities. Never changed the barrel on my second most used rifle, a Remington Mohawk in .308 and it got shot a lot. That same barrel in on the rifle (a friend has it) years later.

I understand the problems with the barrel burning calibers, but you might want to read Humpy's word about "The Carbon Wars". That's another bore killer.
 

·
Registered
Joined
·
6,190 Posts
From time to time we have members posting asking if anyone can predict how long their particular rifle's bore will last before requiring rebarreling. Perusing an old July 2009 issue of Field and Stream Magazine, it contained the following information as compiled by writer, David E. Petzal. I have edited the article for the salient points:

Every time you ignite a cartridge, some 5,000 to 6,000 degrees of heat is applied for a few thousandths of a second and at whatever chamber pressure the cartridge individually develops. This causes steel to melt. This is called "erosion". The more powder to burn and form gas pressure, the faster the erosion. A small case capacity with slow burn rate powders will not erode as fast as large (and overbore) capacity cases with faster burn rate powders. A fast burn rate powder will burn hotter than a slower one.

Stainless steel resists the damage of heat/pressure more so than chrome/moly steel.

Now, some generalities of useful barrel life, based on factory loaded standard ammo:

.223 Remington (3,000 to 4,000 shots)

22/250 Remington (2500 shots)

.270 Winchester (3,000 shots)

7mm Remington Magnum (1,500 shots)

30/30 Winchester (6,000 + shots) He says "God only knows, never saw one shot out!

30-06 (4,000 to 5,000 shots)

.300 WSM (2,000 shots)

.300 Weatherby (1,000 to 1,500 shots)

.338 Winchester Magnum (2,500 to 3,000 shots)

An interesting side note: gunsmith Melvin Forbes told Petzel he saw something like 3,000 rifles come in for rebarreling, but only found 3 that were actually shot out. The other 2,997 were due to neglect in not cleaning or improper cleaning.

Moral of post - don't overheat the barrel while shooting (should be able to keep hand comfortably grasping barrel), use the slowest powder that provides adequate accuracy, be knowledgeable of proper cleaning techniques and clean when accuracy tails off.

Used to get around 7-8,000 rounds through my old USGI NM M14 barrels. I can update when I shoot out the barrel on the standard grade I'm using and screw on a Kreiger.

A Garand with a Criterion is doing fairly nicely now that I'm beaten some cleaning sense into the owner.
 

·
Registered
Joined
·
423 Posts
A little anecdotal evidence.

I once had a 22-250 on a Model 70 action. I wore it out in about 2200 rounds. Bullets began keyholing.

My first 7mm magnum on a 98 Mauser action began keyholing right at 2000 rounds. It's been rebarrelled and has been fired about 400 times to date.
 

·
Registered
Joined
·
1,120 Posts
I have a Rem. 700 264 mag with a factory stainless Bbl. I bought this rifle new in 1964. It has taken literally tons of deer & elk over the years & has well over 2000 rounds thru it. Still shoots under an inch. I only shoot 1 or 2 shots to check the zero before the hunt. I have used only my own hand loads with extreme slow burning powders like 5010, H-870, etc. I have "NEVER" shot more than 3 shots & usually no more than 2 without cooling the barrel. If warm I rub the barrel with a rag & 70 or 90% rubbing alcohol till cool. The alcohol evaporates fast & pulls the heat right out in about 4 or 5 minutes. If you have a blued steel barrel be sure & re-oil your barrel when finished shooting. Don't abuse your barrel & it will last far longer than you would think.
 

·
Registered
Joined
·
72 Posts
It basically boils down to this. The faster the bullet the shorter the life span of the barrel (unless crome lined bores like the AR15). The ones I have seen that seems to shoot themselves the fastest are the single shot rossi's. I got my son one for his first deer rifle and he took a 6 point with it on his third day on his first hunt. 3 seasons later and it started shooting shot gun patterns at 100 yards. Now after about the same time frame my buddies son's 243 is starting to do the same thing. I think they are the Saturday night specials of rifles.
 

·
Registered
Joined
·
400 Posts
Recoil junky,
I also have a 788 junker field gun in 22-250, I have had this gun since 1977 and have put well over 3k plus
rounds through it and I bought it used, it will still hit quarters at 300 yards. I know it's days are numbered. The old 788 was quite a deal back then.
Just wondering how yours was used. I bought one in 67 and put over 1200 rounds through it in the first year. The gilt edge accuracy was gone at that time. I tried to keep it clean using Hoppes (only thing we had) but the sessions shooting rapid fire at running coyotes, jacks over wheat fields, and sometimes at prairie dogs generated a lot of barrel heat and I've always blamed that for the early demise of accuracy. My load was the Hornady 55 sp pushed by 35 gr of IMR 4320.

Similarly, my 700 243 lost it (very noticeable eroded throat) around 1800 but it shot well enough for deer if you didn't clean the barrel. Load was 87 sp pushed by 46.5 gr of surplus 4831. There were times I'd have the barrels of either rifle so hot they would burn you.
 

·
Registered
Joined
·
6 Posts
Any advice? Browning Xbolt .223

I recently bought the Browning xbolt varminter in .223. The barrel is 1-12 twist. I have tried several different rounds to try and find the most effective/accurate round to choose. I have had pretty good luck with the 55 grain Winchester Silvertip, but was wondering if there was a better round out there. Looking just to hunt coyotes etc. Any advice would be greatly appreciated.

Thanks
DIAMOND L
 

·
Registered
Joined
·
2,055 Posts
You want your gun to last forever? Shoot lead alloy and use faster powders like Unique or Red Dot. As a practical matter, the bore will last forever. Speed is good on occasion, but as a general matter, my 30-30 with Red Dot or whatever with a 170 grain cast bullet makes me real happy. I do enjoy knowing that there are people shooting 1,000 yards and then some. And yes, I have some slower burning "rifle" powders, but I am a cowboy at heart. This is my world.
Lever Gun Performance Studies
 

·
Registered
Joined
·
2,862 Posts
It basically boils down to this. The faster the bullet the shorter the life span of the barrel (unless crome lined bores like the AR15). The ones I have seen that seems to shoot themselves the fastest are the single shot rossi's. I got my son one for his first deer rifle and he took a 6 point with it on his third day on his first hunt. 3 seasons later and it started shooting shot gun patterns at 100 yards. Now after about the same time frame my buddies son's 243 is starting to do the same thing. I think they are the Saturday night specials of rifles.

So how many rounds did that?? I guess someone would know it if it was 1000-2000, ie someone had to buy or load the ammo.
 

·
Registered
Joined
·
2,265 Posts
I have a 7mm RM, Rem 700 actually, 26" SS barrel. That rifle has had over 6k rounds of worked up max loads run through it, all slow burning powders, and the barrel just doesn't go away. OTOH, I have another Rem 700, not stainless steel, I shot that barrel out in less than 2k rounds, it was almost a smooth bore when I re-barreled it. Funny thing though, even though velocity fell off drastically, accuracy never did suffer. I could drop a .277" projectile down the barrel without it ever touching the lands,

Back in the 80's I was shooting a custom M98 7mm RM, Douglas. That barrel burned out in just over 1k, but it saw some long days at the range too, and probably got a little too warm on a few occasions also.

I have had probably a dozen .270's, one had some where in the neighborhood of 10k rounds of worked up max slow burner's run through it before I started noticing obvious signs of barrel erosion. It's interesting what proper shooting and barrel care can do to help the life of a factory grade barrel.

I'm currently loading for a couple of 22-250's, both have had at least 2k rounds put through them, one is starting to noticeably slow down, while the other is still going pretty strong, though I think it's about to have seen it's better days in the past.

I started my high powered rifle craze with a Rem 700 ADL chambered in .270 win.. I bought it new, think I spent $159 for it from K-Mart. I immediately took it over to my my late friend and mentor, an accomplished BR shooter, to show it off, and see if he would teach me how to do a trigger job, float the barrel, lapping and all that good stuff. As soon as I told him it was a .270 win. the first words out of his mouth were, so you bought a barrel burner, huh.

I immediately wanted to do a load development, something he mentored me with, and then ran those 130 grainers across his chony. I was pleased as pie, they were flying nice and straight and running about 3100 fps with my current development. After I had reloaded and shot in excess of 10k rounds through that barrel, my late friend asked me if I wanted to run it across the chrony again, stating that it's probably done. But I responded no way, it's still a tack driver. To my shock, the same trusty load that had shot 3100 fps was running just under 3000 fps, that barrel was finished. I still used it for a while before re-barreling it.

My point being, that just because a barrel may still shoot straight, doesn't always mean it's not shot out. Often times, well at least in my experience, barrels will slow down when reaching the end of their life, some may not even lose their accuracy until on their last leg.

SMOA
 

·
Registered
Joined
·
354 Posts
Submoa,
Great information! I had a Ruger American in 243 Win that I played with developing some pretty hof loads for. I mean 55 grainers @ 4025 over a chronograph hot. Not many hot loads, but enough to know the rifle.
@ 2000+ rounds, Ruger suggested l send the rifle back for bore scoping as the groups started to open up. I expected a rebarrel, but instead they sent me a new rifle.
I'm currently working up new loads for this gun based on OCW accuracy at the lowest practical speeds(first node).
Keeping the barrel cool and reasonably clean( I was anal about cleaning the last one), I figure it should outlast the old one, but we will see.
Seems that smaller charges of faster powder with short bullets allow the barrel to cool faster than bigger charges of slow powder with longer bullets. More friction with longer bullets?
Anyway, its a great day to go out back to my bench and continue testing.
 

·
Registered
Joined
·
13 Posts
The .270 is probably similar to the .308 in that normal barrel life is likely around 3000-4000 with chrome moly and maybe 500 more with stainless. That is based on Sierra's testing, which did not let the barrels cool a lot between rounds, I expect. In a .308 they got 3000 in CM steel and 3500 in ss. Their criterion was more sensitive than some shooters can manage, which was the first appearance of a flier. Since they have machine rests set up and use only bullets from a special set aside extra accurate lot of 168 grain SMK's that serve as their reference ammo, they could identify that moment pretty certainly. Cryo treating then extended their ss barrel life by about 15% or 20% IIRC.
UncleNick, I have anecdotal data about a specific 308 barrel, using different criteria from Sierra. Shooting 308 in a Winchester 70 SS, my average 5-shot group accuracy went down by 35% after 6,500 rounds, after which I re-barreled. I clean my barrel roughly every 50-60 rounds, or before I put my rifle away for a season. I don't shoot my barrel fast or hot.

Not conclusive by any mean of course - but one data point that may be useful to others.
 

·
Registered
Joined
·
31 Posts
I managed to shoot one out. It was a 7 x 64 Sharpe and Hart. Shot it a LOT working on long range. Had the rifle rebarreled and rechambered to 7MM Mag. The action stretches cases, though. Shutlze and Larsen.
 
161 - 180 of 206 Posts
Top