I know you can't really "fix" a pitted bore, but is there a way to at least make one shootable? I've got a K98k that can't group even at 50 yards. Anything to be done or just get rid of it and look for a new one?
Cleaning a pitted bore?
- Thread starter npconnor
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In your case I think you would have nothing to loose by trying an electronic cleaning system.
There is plenty of info on the internet about building your own set up but I'll try and give you the highlights.
Use a cell phone charger that is going to put out .3 milli-amps.
Go to the welding supply shop and get one rod of 3/32 stainless steel TIG welding rod.
Hardware stores sell the o-rings to insulate the SS rod from the barrel.
Find a funnel that you can slip onto the barrel, tape in in place to catch any over-flow that may bubble up above the top of the muzzle.
You can home brew the solution, or buy it from midway usa.
Recipes for home brew are available online.
Degrease the barrel before you use the electro-cleaner, oil and grease will inhibit the cleaning action.
After using the electro-cleaner run some of the J-B non-embeding bore paste through it to finish the process.
Using an electro-cleaner is not a set and forget process. You'll need to use a brush and your normal bore cleaner between sessions of electro-cleaning to get carbon out. Stay in the general area and keep an eye on things.
It'll take a few cycles of electro-cleaning and brushing, with degreasing in between but it'll get the bore back down to bare steel.
If you run the cleaner too long (like over night), or at too high of an amperage setting it will harm the barrel but it's pretty hard to actually do that. You would need to use a car battery charger for power supply, or leave the thing running over night but it's a worthy caution all the same.
If you read up on the info readily available online (make sure you are reading stuff written by people whom have actual first hand experience with this...) for an hour or so you'll be good to go.
I would not recommend this for general cleaning but in your case I think it'll do your rifle a lot of good.
There is plenty of info on the internet about building your own set up but I'll try and give you the highlights.
Use a cell phone charger that is going to put out .3 milli-amps.
Go to the welding supply shop and get one rod of 3/32 stainless steel TIG welding rod.
Hardware stores sell the o-rings to insulate the SS rod from the barrel.
Find a funnel that you can slip onto the barrel, tape in in place to catch any over-flow that may bubble up above the top of the muzzle.
You can home brew the solution, or buy it from midway usa.
Recipes for home brew are available online.
Degrease the barrel before you use the electro-cleaner, oil and grease will inhibit the cleaning action.
After using the electro-cleaner run some of the J-B non-embeding bore paste through it to finish the process.
Using an electro-cleaner is not a set and forget process. You'll need to use a brush and your normal bore cleaner between sessions of electro-cleaning to get carbon out. Stay in the general area and keep an eye on things.
It'll take a few cycles of electro-cleaning and brushing, with degreasing in between but it'll get the bore back down to bare steel.
If you run the cleaner too long (like over night), or at too high of an amperage setting it will harm the barrel but it's pretty hard to actually do that. You would need to use a car battery charger for power supply, or leave the thing running over night but it's a worthy caution all the same.
If you read up on the info readily available online (make sure you are reading stuff written by people whom have actual first hand experience with this...) for an hour or so you'll be good to go.
I would not recommend this for general cleaning but in your case I think it'll do your rifle a lot of good.
GBExpat
Member
There is a good chance that the pitted bore is not the problem but, rather, a worn muzzle. As a crude test, insert a cartridge, bullet first, into the muzzle until it stops ... how much of the bullet is still visible?
If only a tiny sliver or none (it sinks right up to the case mouth) of the bullet is visible, your muzzle is probably too worn to group.
Also an unevenly worn muzzle can be the cause of the issue you describe.
tahoe2
Member
pitted barrel
I also have a German M98k (duv-41) with a pitted barrel and strong rifling, it seems the more I shoot it the better it gets. I have put a couple hundred rounds through it, in three years, it used to shoot 6"-8" groups @ 100yds, now it shoot's 3"-4". When I first got it, I would shoot a full mag (5 rnds) and then clean it (while the barrel is hot), I did that for 50 rnds and it cleaned up pretty nice. It is still dark but the rifling is more pronounced. I don't know if yours will come back in, but if not, you could just put a new/used 98 military barrel back on it. If you don't want it to stay military style, there are plenty of aftermarket barrels available.
I also have a German M98k (duv-41) with a pitted barrel and strong rifling, it seems the more I shoot it the better it gets. I have put a couple hundred rounds through it, in three years, it used to shoot 6"-8" groups @ 100yds, now it shoot's 3"-4". When I first got it, I would shoot a full mag (5 rnds) and then clean it (while the barrel is hot), I did that for 50 rnds and it cleaned up pretty nice. It is still dark but the rifling is more pronounced. I don't know if yours will come back in, but if not, you could just put a new/used 98 military barrel back on it. If you don't want it to stay military style, there are plenty of aftermarket barrels available.
It might be a muzzle problem. If you find that the muzzle is nicked or worn out you might be able to find a gunsmith to counterbore your muzzle for you. I have a Mosin that has been counterbored and it shoots great.
Thanks for the suggestions, I'll look into making my own electro-cleaner. Should be a fun experience.
I'll be sure to check this, can't believe I haven't done that yet.
Yeah, mine has strong rifling but the bore is dark and pitted to hell. I looked into getting a new action + barrel from http://www.rguns.net/ but I kept reading bad reviews that what they had was just nasty dark bores with little rifling left.
I'll be sure to check this, can't believe I haven't done that yet.
Yeah, mine has strong rifling but the bore is dark and pitted to hell. I looked into getting a new action + barrel from http://www.rguns.net/ but I kept reading bad reviews that what they had was just nasty dark bores with little rifling left.
The pitted bore can be a problem in group size. Have you also considered the bore diameter? You may want to check the diameter and use the right sized bullet to fit. Possibly your barrel may be oversized and .308 bullets just wobble down the barrel. Just a thought.
morcey2
Member
Check the crown. The Spanish K98 ( air force M44 ) that my dad gave me was having the same issue. The crown didn't have any serious dings, but many little ones. I recrowned it and it went from a 10" group @ 30 yards to 1.5" groups @ 100.
Get some Yugo M75 surplus ammo if you can find it. Very accurate, but remember to clean after as it's corrosive. Speaking of which, what ammo are you using? I've never been able to get any of the big three domestic 8mm loads to group well in any of my mausers.
Matt
Get some Yugo M75 surplus ammo if you can find it. Very accurate, but remember to clean after as it's corrosive. Speaking of which, what ammo are you using? I've never been able to get any of the big three domestic 8mm loads to group well in any of my mausers.
Matt
tahoe2
Member
Robert101
That mauser should be shooting .323 bullets not .308, you might be confusing that photo of the Mosin Nagant (7.62x54R) with a Mauser 8x57.
npconner; morcey is right, I would try the re-crown method before writing that barrel off, and also check bore dimensions. You can get cast bullets up to .325-.326, but that's a handloaders deal. Good Luck and keep us posted.
That mauser should be shooting .323 bullets not .308, you might be confusing that photo of the Mosin Nagant (7.62x54R) with a Mauser 8x57.
npconner; morcey is right, I would try the re-crown method before writing that barrel off, and also check bore dimensions. You can get cast bullets up to .325-.326, but that's a handloaders deal. Good Luck and keep us posted.
Skylerbone
Member
The simplest solution would be a good cleaning and inspection of the sights and muzzle (as previously described) to start with, no need to be overly aggressive.
Assuming you're shooting irons, though the same applies to optics, check everything that can be checked. Start cleaning with Sweet's and shoot it. Progress to JB Bore Paste if needed. JB will get you to bare steel faster than you might think so proceed in stages if improvement is noticed.
It's a good idea to establish ahead of time an acceptable threshold for accuracy. Your current barrel may never be capable of more than X at 100 yds. without spending more or chancing a bit of home modification that may not improve things substantially.
Assuming you're shooting irons, though the same applies to optics, check everything that can be checked. Start cleaning with Sweet's and shoot it. Progress to JB Bore Paste if needed. JB will get you to bare steel faster than you might think so proceed in stages if improvement is noticed.
It's a good idea to establish ahead of time an acceptable threshold for accuracy. Your current barrel may never be capable of more than X at 100 yds. without spending more or chancing a bit of home modification that may not improve things substantially.
tahoe2
Member
morcey2 said:
I'll take some detailed pictures of my crown for you. If I recall, it's not in great shape. I'm using PPU (Prvi Partizan) this stuff is amazing in my No.4 Mk2 in .303 Brit and I got a killer deal on a lot of it. So surely it's not the ammo.
tahoe2 said:
I'll do the bullet trick and see what's what.
skylerbone said:
Any more information on this "Sweet's?" I think I know where to get JB bore paste.
I'm not expecting sub-moa from this thing. But as long as I can get minute-of-man at 600m I'm good. That's the farthest I shoot. My Mosin, FAL, M1 Garand, etc... all seem to be able to do that just fine.
I'm a University student and won't be home to check on the rifle until Nov 20th.
Skylerbone
Member
Available at Brownells, MidWayUSA, Cabelas, Gander Mountain, (lots of places). http://www.brownells.com/gun-cleaning-chemicals/solvents-degreasers/bore-solvents/sweet-s-7-62-bore-cleaner-prod1404.aspx
Remember on those pictures the crown is the very last point of bullet contact at the muzzle. Just pointing it out as many snap a pic highlighting nicks and dings around the outer barrel circumference. Careful macro pictures with natural lighting work best.
Remember on those pictures the crown is the very last point of bullet contact at the muzzle. Just pointing it out as many snap a pic highlighting nicks and dings around the outer barrel circumference. Careful macro pictures with natural lighting work best.
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