Gunsmithing How do you know if your barrel is shot out?

[citysmasher]

I have a 223 Rem 700 that I built from an old Police/tactical back in 1998/1999. It was used when I got it (someone made it into a position gun with a position stock and match sights).

I full length bedded the whole action into a Zero laminated tactical stock (Bisonite bedded). The action and barrel out 3" is bedded and floated from there. This gun always shot well (it really used to hammer), and the moly bullets kept the fouling to a minimum in the factory barrel.

I figure I put about 2000 rounds through it (I have no idea how many rounds were through it when I bought it). A lot of hot 40 grain rounds in one PD hunt. I was shooting my 52 SMK loads today across a chrony, and I was surprised to see these were 3400 FPS!!!

Anyway, I use it for my short range practice gun. Recently, it does not want to group 5 shots. It will group 2-3, and then move and group 2-3. It shoots better after a cleaning now. It never cared how much you cleaned it before. Now, all of a sudden it wants to be cleaned. The first group of the day is the best one. That did not used to be case. Today, it shot some 2" groups. Never saw that...

I had a Kreiger 1-7.7 in my AR space gun that I used for across the course. It did nothing weird (ever), and really did not care if you cleaned it or not. It was also much more forgiving to bullets and loads, and would shoot 1/2 MOA with cheap bullets. My Rem just seems to get touchier and touchier.

Well? I suppose I know the answer...

 

[Hateca]

Re: How do you know if your barrel is shot out?

Clean it and that may help, but 2000 rounds down the barrel is not enough unless you did something really bad to it. Without you knowing the past history and round count it could be possible that the barrel is toast.

Don't try and shoot moly then naked bullets without cleaning. Some barrels just don't like the switch.

But I would also look at the scope set up. Base and rings, see if they are secure. Check the scope and see if it took a shit. Check the rifle with a known good scope. If you are getting two distinct grouping this is one sign of an optic or mounting problem.

Check the crown as well, and not just by eye have someone with a borescope look at it from the inside. Have them look at the throat as well.

 

[citysmasher]

Re: How do you know if your barrel is shot out?

I just mounted a new scope. New mounts too.

 

[Ol Rob]

Re: How do you know if your barrel is shot out?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Citysmasher</div><div class="ubbcode-body">I just mounted a new scope. New mounts too. </div></div>

This my be more than coincidence<sp>? Triple check everything about the scope, rings, base screws, paralax adjustment.
Have you fully strip cleaned the barrel? I would do a full monte cleaning for moly, carbon and copper then fire 20-30 fouling shots before judging results. Just my 2cents. YMMV
Rob

 

[dar1246]

Re: How do you know if your barrel is shot out?

Check your lands. My sons 243 went from 2.890 to 2.994. Clean the barrel and shot 6 rounds through it. Then clean it again. It didn't have any powder residue but tons of copper. The accuracy was great downhill.

 

[citysmasher]

Re: How do you know if your barrel is shot out?

I suspected the scope (or mounts) right away.

It simply would not group after installation. The mounts are Leupold quick release and I have another scope on my 308 with the same mounts. The mounts are tight (they have been triple checked) and the cam over is hard, so I suspect the scope (even though it is brand new). I can drop my 308 scope on this rifle, and even switch back and forth. If the scope is OK, it must be the mounts.

The parallax is quite good as far as I can tell. I cannot make the zero move with my head. Especially not enough to account for 2" groups. This gun was shooting 3/8 MOA to 1/2 MOA pretty consistently, and that is for 5 shot groups.
I can even throw this scope on my 308. No problems with that rifle.

The lands are in tact. The bullet jump in this rifle is only .072" from standard length with SMK 52 bullets (OAL length 2.230).

Truly, I do not see any copper coming from my barrel, only moly. I never shoot naked bullets.

 

[Greg Langelius *]

Re: How do you know if your barrel is shot out?

I would do a quick and dirty load confirmation/redevelopment just a little above and below the existing accuracy charge, to confirm that neither the gun nor the components have altered the accuracy load.

Two-grouping could be an indicator that bedding may not be optimal, maybe stripping and rebedding could help.

The appearance of the problem in close association with a scope alteration should mean something, but that should also respond to a swap test.

The other suggestions make sense too.

Greg

 

[Greg Langelius *]

Re: How do you know if your barrel is shot out?

One assumes you do not have access to a borescope.

Unmistakable evidence via a borescope:

Rifling washout anywhere along the bore, but especially in the first few inches.

Checkerboard heat damage patterns in the throat area show progressive bore deterioration, and any of those checkers having the 'block' missing is a basic "all she wrote" declaration.

Depending on the overall quality and condition of the barrel, It may be possible to set the barrel back, which involves removing enough length from the chamber end, then rechambering, rethreading, and headspacing the barrel. Because the tendency of the more typical patterns of bore wear is to develop a taper to the bore, broader at the chamber end, a 'choking' effect develops, and has been known to increase accuracy for barrels that have been set back. Some will suggest that a factory barrel is not worth the effort, and they could well be right. But if the barrel shows good bore condition aside from the portion which will be discarded, and has displayed good performance prior to the accuracy fade, it becomes a matter of shooter preference.

A good barrel is not defined by its cost, it's defined by its performance.

Greg

 

[Lumpy Grits]

Re: How do you know if your barrel is shot out?

Just for "grins" I would have the crown redone and see what that does.
You do clean from the chamber,right??
Respectfully,
LG

 

[citysmasher]

Re: How do you know if your barrel is shot out?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: lumpy grits</div><div class="ubbcode-body">Just for "grins" I would have the crown redone and see what that does.
You do clean from the chamber,right??
Respectfully,
LG </div></div>

Yes. Absolutely.

I think it is the scope. The vendor will stand behind the scope if it defective (which is good). I will just have to test it.

I would like to have the bore scoped.

 

[Smokin]

Re: How do you know if your barrel is shot out?

Are you shooting high pressure loads? I burned out my .308 in around 3K rounds shooting extremely high pressure loads. I went through this same process of not believing my barrel was toast until I finally sent it to GAP and they told me it was toast as well.

 

[Hateca]

Re: How do you know if your barrel is shot out?

Also if you just put on new mounts be sure the front scope base screw is not too long and pushing on the barrel shank. This can cause issues.

 

[Bacarrat]

Re: How do you know if your barrel is shot out?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Smokin</div><div class="ubbcode-body">Are you shooting high pressure loads? I burned out my .308 in around 3K rounds shooting extremely high pressure loads. I went through this same process of not believing my barrel was toast until I finally sent it to GAP and they told me it was toast as well. </div></div>

Hey Smokin, do you know if your previous barrel was a tight bore or not?

 

[gun-rx]

Re: How do you know if your barrel is shot out?

I'd put my money on throat erosion. 3000 rounds is normally where one sees a significant accuracy loss. Sierra conducted a test a number of years ago on barrel life. They used 2 Hart stnls barrels, a Douglas stnls. ( I believe), and a Black Star. Keeping record of the number of shots through each barrel, they all went south between 3000 and 3300. This test was published in Precision Shooting. From what I've seen in my career, I agreed with their findings.

 

[citysmasher]

Re: How do you know if your barrel is shot out?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: HateCA</div><div class="ubbcode-body">Also if you just put on new mounts be sure the front scope base screw is not too long and pushing on the barrel shank. This can cause issues. </div></div>

Wow...

I was shocked to find when I assembled the front mount that the bolt would not close with the rear screw installed. I had to shorten the screw. So, I did that when I installed it. Maybe the screw is still too long?

How would I know if it is pushing on the shank? Wouldn't it scratch the bolt?

 

[Hateca]

Re: How do you know if your barrel is shot out?

Not the second screw the very front screw. It is sort of like a blind hole. The hole is over the shank of the threaded barrel. If the screw is too long it will push on the shank and this can cause you issues.

A simple way to check is put that screw in first and only that screw, torque it down. If it's too long it will bottom out on the shank and the base will still wiggle around.

If the second screw is also too long and still hitting the bolt lug, then yes this to will cause you issues.

 

[bra260]

Re: How do you know if your barrel is shot out?

If you can hear the bullets rattle down the barrel!

 

[Hateca]

Re: How do you know if your barrel is shot out?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: gun-rx</div><div class="ubbcode-body">I'd put my money on throat erosion. 3000 rounds is normally where one sees a significant accuracy loss. Sierra conducted a test a number of years ago on barrel life. They used 2 Hart stnls barrels, a Douglas stnls. ( I believe), and a Black Star. Keeping record of the number of shots through each barrel, they all went south between 3000 and 3300. This test was published in Precision Shooting. From what I've seen in my career, I agreed with their findings. </div></div>

What caliber? What load date? No two calibers are the same. Hell even the same calibers can be different depending on the load.

Maybe for their test and load but I have a .223 that has about 7000 rounds and it's still going strong. I have seen .308 go 10,000 rounds and some go 3000 rounds, depends on too many variables. So a blanket statement based on one test with no details is stretching it.

His barrel my be toast but this history is in question and a scope change was recent so before I would definitely say it's the barrel there are other things to consider.

 

[citysmasher]

Re: How do you know if your barrel is shot out?

I do not think 223 is hard on barrels.

This is a great thread. I would love to hear more.

 

[citysmasher]

Re: How do you know if your barrel is shot out?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: HateCA</div><div class="ubbcode-body">Not the second screw the very front screw. It is sort of like a blind hole. The hole is over the shank of the threaded barrel. If the screw is too long it will push on the shank and this can cause you issues.
</div></div>

No sh@t...

 

[Hateca]

Re: How do you know if your barrel is shot out?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Citysmasher</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: HateCA</div><div class="ubbcode-body">Not the second screw the very front screw. It is sort of like a blind hole. The hole is over the shank of the threaded barrel. If the screw is too long it will push on the shank and this can cause you issues.
</div></div>

No sh@t... </div></div>

....No sh@t.

 

[DMS]

Re: How do you know if your barrel is shot out?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Greg Langelius *</div><div class="ubbcode-body">I would do a quick and dirty load confirmation/redevelopment just a little above and below the existing accuracy charge, to confirm that neither the gun nor the components have altered the accuracy load.

Two-grouping could be an indicator that bedding may not be optimal, maybe stripping and rebedding could help.

The appearance of the problem in close association with a scope alteration should mean something, but that should also respond to a swap test.

The other suggestions make sense too.

Greg </div></div>

Greg is correct about resetting a barrel working sometime. However, it usually works best when done prior to the bad being shot out. Meaning that if you know a specific caliber usually stops shooting well at 3000-3500 rounds, you set it back at 2500. It also works better with stainless barrels than chromemoly as cromemoly wears in a different pattern in the throut area.

 

[DMS]

Re: How do you know if your barrel is shot out?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: HateCA</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: gun-rx</div><div class="ubbcode-body">I'd put my money on throat erosion. 3000 rounds is normally where one sees a significant accuracy loss. Sierra conducted a test a number of years ago on barrel life. They used 2 Hart stnls barrels, a Douglas stnls. ( I believe), and a Black Star. Keeping record of the number of shots through each barrel, they all went south between 3000 and 3300. This test was published in Precision Shooting. From what I've seen in my career, I agreed with their findings. </div></div>

What caliber? What load date? No two calibers are the same. Hell even the same calibers can be different depending on the load.

Maybe for their test and load but I have a .223 that has about 7000 rounds and it's still going strong. I have seen .308 go 10,000 rounds and some go 3000 rounds, depends on too many variables. So a blanket statement based on one test with no details is stretching it.

His barrel my be toast but this history is in question and a scope change was recent so before I would definitely say it's the barrel there are other things to consider.
</div></div>
Also depends on range you are shooting at. I have barrels that still hammer at 200 yards, but groups are opened up at 300, and will get fliers at 600. Thats why my course gun upper for one year becomes my 200 yard practice upper the next year and the first upper gets a new barrel.I get about 3500 rounds on a Krieger before I stop using in full distance matches. I know it earlier than alot of people suggest, but I would rather know I have a good shooting barrel than have doubts.
The type of barrel making process is a huge factor as well. Cut rifle barrels will tend to shoot well longer than button rifled barrels. Stainless barrels also tend to give up their accuracy in a more gradual way than chromemoly barrels. This is due to how the throat wears. Chromemoly tend to loose chunks of throat after so many rounds (as Greg pointed out earlier).

 

[Downzero]

Re: How do you know if your barrel is shot out?

I'm willing to bet that it has way more rounds through it than you think, and that it's shot out.

On the plus side, I'm looking forward to that day for my rifle. The new tube will undoubtedly out-shoot the old.

 

[LOSTDOT]

Re: How do you know if your barrel is shot out?

ive got a 223 ruger heavy s/s barrel on my mki and is at 11500 rounds and counting. got it recrowned at 8000 and i have had mates look at it and 2 of the 3 reckoned it was a reasnobly new barrel.

 

[tmxring]

Re: How do you know if your barrel is shot out?

I would have the barrel scoped by a smith to make sure the throat is still good. Also check the crown, boat-tail bullets can "fish-mouth" the muzzel. If it's a custom tube I'd set it back and re crown(if needed). If it's a factory barrel, take it off and make a tomatoe stake out of it.

 

[citysmasher]

Re: How do you know if your barrel is shot out?

After determining, (by counting the number of rounds) that it was quite possible the front screw was bottoming against the barrel, I shortened the screw and took "Red" (my 223) to the range with some "money" loads.

I mounted my old B & L Elite 4000 (what was on the gun before I switched to the Bushnell Tactical) and shot a 5 shot group.

Bug hole. Maybe 1/4" with one flier that opened the group up to 3/8". That is pretty good for an old factory gun with a factory trigger.

So then I put on the new 30mm tactical (I have quick release mounts). The first thing I noticed is that this scope looks like crap compared to my old BL 4000!!! I never got the target crisp. I think my old made in Japan BSA might be more clear than this thing. My BL 4000 is so clear it is ridiculous.

The optics on the new scopes suck... the rifle scope business has gone to crap while I was on hiatus from shooting.

In regards to the barrel, I do believe it is starting to not shoot as well after a number of rounds. It shoots best after being cleaned.

 

[citysmasher]

Re: How do you know if your barrel is shot out?

I did not mean to kill the thread. I really want to know if there are an "signs" the barrel is giving up.

 

[Hateca]

Re: How do you know if your barrel is shot out?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Citysmasher</div><div class="ubbcode-body">I did not mean to kill the thread. I really want to know if there are an "signs" the barrel is giving up. </div></div>

Maybe, maybe not. I have seen barrels shoot great one group and the very next go completely south. Then I have seen barrels where the groups gradually open up and nothing you do will bring it back. So to say there is a particular sign, I say no.

There will be a combination of things that will lead you to suspect the barrel. Round count, how hard you push the cartridge, how hot you get the barrel before you let it cool, and several other factors. Take all of those into consideration then you can start to question the barrel.

A guy shooting hot and fast .308 loads may only get 3000 rounds before the barrel goes to crap. If he shoots lots of comps that require fast rates of fire he may get less. Other .308 barrels that are well within the pressure curve can go as high as 10,000 before the barrel goes to crap.

 

[sobrbiker883]

Re: How do you know if your barrel is shot out?

Mind sharing which scope it was that caused your problem?

 

[Greg Langelius *]

Re: How do you know if your barrel is shot out?

If it shoots best after it's cleaned, it's best suited to CCB shots only. Redevelop the load for fouled bore, i.e., shoot ten rounds just to foul, <span style="font-style: italic">then</span> start testing increments for accuracy.

Greg

 

[citysmasher]

Re: How do you know if your barrel is shot out?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: sobrbiker883</div><div class="ubbcode-body">Mind sharing which scope it was that caused your problem?

</div></div>

None of the scopes were actually defective, so it appears the mount screw might have been the problem.

With that being said, none of the new scopes I tried will touch my old BL Elite 4000. Optics have really gone downhill in mid range scopes. The old BL's and Nikons from the 1990's would blow the new ones out of the water.

Isn't industrial globalization great? Scopes made in 3rd world countries are great!!!!

 

[citysmasher]

Re: How do you know if your barrel is shot out?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Greg Langelius *</div><div class="ubbcode-body">If it shoots best after it's cleaned, it's best suited to CCB shots only. Redevelop the load for fouled bore, i.e., shoot ten rounds just to foul, <span style="font-style: italic">then</span> start testing increments for accuracy.

Greg </div></div>

Interesting... what effect on the load do you believe a fouled barrel would have? Do you think the fouling would change the OBT?

 

[sobrbiker883]

Re: How do you know if your barrel is shot out?

Fouling won't change the OBT much, but a certain amount of fouling may smooth up the bullet's ride to the muzzle in an otherwise choppy tube....
Accuracy is all about consistency, and Greg's post really made sense to me concerning tubes that shoot better clean, then fall off quickly, or shoot better fouled and open up after a thorough scrubbing.