How many 308 rounds does it take you to foul a barrel?

MartyK2500

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Today was a new learning experience.
I had prepared this very nicely crafted ammo, as I get bored and it's the only thing to do right now!
Sorted by bullet weight, measured all powder charges twice on my FX120, loaded 90 rounds, and only set aside 25 rounds that had absolutely 0 run out, the perfect ammo.

Was going to set my new personal record out at 200M (which is 5 groups of 5 rounds each at 200M, all sub 1/2 moa, under 30-35 minutes).
But something had eluded me, powder and possibly copper fouling.
Last time I went shooting, it was raining hard, and decided to shoot in the rain for my personal experience, to see how ammo and hits on target would react.
After that visit I did a full strip/clean/lube, which included a full bore maintenance and reset copper fouling.

Before going for my group this morning, I thought to myself 5 fouling shots and i'm all set to go.
Looking at the target, which I have numbered the sequence I shot them at, I would now think it takes about 15 shots to foul my barrel good.
This is at 200M. Funny how the cluster moves around while fouling is settling.
I am curious if next range visit will pick off where my last group (#5) was at, Zero wise.

How many shots does it take for you guys to foul a barrel properly after a full copper removal?

(paper tear on top right is me removing staple too hastily, the cluster is that tight)
pQjg2dRh.jpg
 
You did not mention the make of barrel.

A hand-lapped custom barrel that has been broken in properly will foul very differently than a factory barrel.

My barrels are the former type. I find it takes 3 shots to foul them. First 3 are half minute and then the bullets bug-hole.

I clean about every 250 rounds. Not because I have to, but because the need to clean just become too strong and I can't hold off cleaning. Then I have to find a way to fire 3 foulers again.
 
My barrel make is IBI.
Custom hand lapped barrel.
More testing is probably required, as i am not a professional shooter and there’s the human factor maybe going on here, even though i am sometimes quick to dismiss it.

In these groups, it looks like less than coincidence that more i shoot the tighter it gets.
My foulers made a 1.250’’ group at 200M give or take.
But these we’re my worst runout ammo too (2 to 2 1/4 thou runout)
 
I never strip out the copper. I use wipeout every 300 rounds (leave in for one hour then patch out). I put 4000 rounds through a Walther barrel that way, always shot great. Now I have a Hardy that was spun up by Insite Arms, shoots amazing.
 
Barrel fouling depends largely on the load you are using.

Think about powder burn rate.. fast burning powders vs slow burning powders.

Slow burning powders are best when alot of powder is used and with heavy bullets.

If the load is using a fast powder for the caliber, it will burn clean and take lots of rounds to foul.

If the load is using a powder with a slightly too slow burn rate, the powder will not burn cleanly and soot will accumulate and accuracy will degrade quickly.

It is for this reason that during load development when choosing between two powders that seem to work well, I always go with the faster of the two.

Not sure if that helps you understand what is happening.
 
I never strip out the copper. I use wipeout every 300 rounds (leave in for one hour then patch out). I put 4000 rounds through a Walther barrel that way, always shot great. Now I have a Hardy that was spun up by Insite Arms, shoots amazing.

Uh, Wipeout can says it clears copper.
 
Barrel fouling depends largely on the load you are using.

Think about powder burn rate.. fast burning powders vs slow burning powders.

Slow burning powders are best when alot of powder is used and with heavy bullets.

If the load is using a fast powder for the caliber, it will burn clean and take lots of rounds to foul.

If the load is using a powder with a slightly too slow burn rate, the powder will not burn cleanly and soot will accumulate and accuracy will degrade quickly.

It is for this reason that during load development when choosing between two powders that seem to work well, I always go with the faster of the two.

Not sure if that helps you understand what is happening.


That was an interesting read,
I have not researched yet if my setup was slow or fast burning
42.7gr Varget with 175 SMK
 
I never use copper solvents to clean a barrel.

Could also just be the "cold shooter" effect.

Because it's an IBI barrel I have to ask - did you shoot the first few groups at a faster rate of fire then the last groups?
 
I never use copper solvents to clean a barrel.

Could also just be the "cold shooter" effect.

Because it's an IBI barrel I have to ask - did you shoot the first few groups at a faster rate of fire then the last groups?


All we’re shot at the same rate.
I had bever acheived accuracy of groups 4 and 5 before, i believe this to be the result of my strict ammo parameters during this test.
Usually, hitting the range, first cold group ressembles group #3.
As i usually do not maintain the bore at all, it suffers very little cold bore effect.
This is 200M speaking, as i am limited to this very short range.

To add to this, all was shot under 30mins.
Last group that has phenomenal grouping, barrel was almost burning to the touch near the barrel nut, before attempting group.
I try not to overheat it without any good reason, but do not like the style of shooting of a round per minute, to impatient for that.
If my 308 barrel dies prematurely so be it, should still last longer than a 6.5 and being a savage small shank prefit means no gunsmith downtime.
 
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If my 308 barrel dies prematurely so be it, should still last longer than a 6.5 and being a savage small shank prefit means no gunsmith downtime.

I have approx 5000+ rounds through my McPhee stainless .308 barrel. I had a good friend bore scope the barrel and we found fire cracking and the first little bit of rifling gone. It still shoots pretty darn good, but there is the occasional WTF shot.........

I will be installing a .30 cal. IBI barrel this fall..........

I expect 2500 to 3000 rounds out of my .260 Rem barrel with the load I am currently running.
 

I have approx 5000+ rounds through my McPhee stainless .308 barrel. I had a good friend bore scope the barrel and we found fire cracking and the first little bit of rifling gone. It still shoots pretty darn good, but there is the occasional WTF shot.........

I will be installing a .30 cal. IBI barrel this fall..........

I expect 2500 to 3000 rounds out of my .260 Rem barrel with the load I am currently running.


Will your IBI be prefit style or you will finish ream yourself?
I am very happy with their prefit tolerances.
I have to headspace myself and have no control over troat lenght.

Tighting my barrel at exactly 1.630’’ headspace, and loading to avg 2.800’’ (as SMKs have varying OAL but constant Ogive), i have exactly a 20 thou jump to the thou close.
Troat has a sharp leade angle, so knowing where lands are at is very predictable and repeatable.
 
Will your IBI be prefit style or you will finish ream yourself?
I am very happy with their prefit tolerances.
I have to headspace myself and have no control over troat lenght.

Tighting my barrel at exactly 1.630’’ headspace, and loading to avg 2.800’’ (as SMKs have varying OAL but constant Ogive), i have exactly a 20 thou jump to the thou close.
Troat has a sharp leade angle, so knowing where lands are at is very predictable and repeatable.

I have someone who will install and chamber the new barrel. ;)
 
Like I said, yes it does take out copper, but it is not going to STRIP OUT ALL COPPER in one application. I’ve been using it for 6 years, I know how it cleans.
 
Like I said, yes it does take out copper, but it is not going to STRIP OUT ALL COPPER in one application. I’ve been using it for 6 years, I know how it cleans.

Depends on how much there is in there. I have done some guns where in an hour it for rid of all of it. I did a second application and patches came out clean.
 
I maintain a copper layer in my barrels. Each barrel behaves a little differently so I watch out for pressure signs and POI shift. It may take several hundred rounds to exhibit signs of excessive copper bore layer, when that happens, I do a light copper removal cleaning with copper solvent and nylon brush. There is another type of fouling I have noticed on my match Shilen (308 win), carbon fouling. After 15-20 rounds it can lose accuracy and groups open up. A quick run thru with oiled and dry patch and everything is back to normal. I actually use very little of Hoppe's 9 solvent for general cleaning, it's just of the carbon but I mostly use oil to clean up.
 
I've been using G96 military bore solvent for my cleaning needs, it seems to do a really good job. Barrel cleaning and care will really depend on the barrel. I haven't owned a custom barrel yet, just factory Remington's and my current SPS Varmint in 308 has been really good about not fouling up. I used a nylon brush for the initial cleaning of the barrel, havn't brushed since. I have just been using G96 soaked on patches, pushing that through the barrel a few times and then 2 dry patches and a light oiling patch or 2. That's it, my rifle has been consitently around 3/4 MOA.
 
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