Improving Old Barrels

[TheAbe]

There might be other posts on this topic, and surely on the subtopics it will involve, but how does one go about improving the performance of old military rifle barrels?

I have an Dutch M95 KNIL carbine and an M91 Carcano long rifle that both fail to stabilize their respective bullets the majority of the time at 25 and 50 yards. Targets have bullet-shaped holes instead of round holes in them. Both barrels slug at .267” and I’ve tried nominally .263”, .265” and .268” jacketed bullets, with no noted improvement. The KNIL has dark, worn grooves with a fair bit of pitting, while the M91 has stronger rifling, but also a fair bit of pitting.

Between re-crowning, fire-lapping, and other processes, what steps would others suggest I take and in what order, to attempt to get these rifle barrels serviceable again?

[steveu]

I have found that using "J" bullets, flat base, round nose work best.

[akajun]

If they’re keyholing with jacketed bullets
Not much you can do other than rebarrel
You can try to counterbore if it’s a muzzle erosion issue but unless you have a lathe, generally not worth it

[Hannibal]

What you are describing is 'keyholing' and it indicates a bullet stability problem. Simply put, the bullet is not spinning fast enough to stabilize. In order to be stable a bullet has to spin when fired. Like a football for instance. If there is not enough spin then the bullet will wobble and turn sideways, which is why you have the bullet shaped side profile in your targets resembling the old skeleton key keyhole. You may already know that but if not it's necessary information to understand the problem.

The bad news is if the bore of your barrels is damaged enough the only viable options you have is to have the bores sleeved with rifled inserts, overbored and new rifling cut which will also require cutting a new chamber or replacement of the barrels.

Firelapping will only increase the bore dimensions and remove more rifling. It's a problem crowning won't correct as it's not just an accuracy issue, it's a stability issue.

I'd suggest finding a competent gunsmithing with a borescope and the knowledge to interpret the images to assess the condition of your bores. Only then will you know for certain what you are dealing with.

[TheAbe]

If they’re keyholing with jacketed bullets
Not much you can do other than rebarrel
You can try to counterbore if it’s a muzzle erosion issue but unless you have a lathe, generally not worth it
I’ll try everything else I can first, if for no other reason than the experience. The KNIL may have some muzzle erosion issues, so I’ll look into counterboring.
If this does become my eventual solution, where can one go to get a new barrel made to the appropriate patterns of these rifles? I’d save up and put the money in if I could get something made that would be the right profile externally and would be cut to accept standard .264” projectiles intended for modern (and old) 6.5mm cartridges.

[TheAbe]

I’ll ask around a couple of long-time shops in the area to see who would recommend a smith. Unless anyone here has recommendations for a good smith in the Twin Cities, MN area?

[schutzen-jager]

is it actually pitting or dark fouling spots ? - try plugging filling bore with white vinegar, let soak for an hour, + than give it a good scrubbing with snug fitting brush -

[TheAbe]

White vinegar. I’ll give it a shot. Fairly sure it’s pitting though, as I’ve given both a good cleaning with Hoppe’s and a wire brush cleaning bit...100 passes on the Dutch.

[Ford SD]

Never had any real bad ones but try

cleaning-with-peroxide-and-vinegar try 15 min flush / clean / repeat as required/ clean / oil
and clean it again with reg gun cleaning stuff in a couple of days as more stuff will loosen up and come out on a patch

https://www.marlinowners.com/threads/cleaning-with-peroxide-and-vinegar.14470/


you can also try plugin the barrel and filling the barrel with eds red (cleaning solution) muzzle down overnight

cast bullets with a gas check use a round nose or a flat nose and do not try to push it too fast try in the 1500 to 1800 fps or stop when groups open up

[schutzen-jager]

forgot to mention - keep vinegar off of any blued surfaces ! -

[Shawlerbrook]

I had some pretty ugly bores shoot pretty good. If the barrel is as clean as you possibly can get it and you are shooting proper sized bullets and they still keyhole the a replacement barrel is the only option.

[rockrat]

I would suggest plugging the bore, filling with transmission fluid and let it sit for a week, then scrub.

[ShooterAZ]

I have had a few sewer pipe barrels "wake up" after shooting several dozen paper patched boolits through them. I've even coated some of the patches with a light coat of JB Bore beforehand. The barrel gets mighty hot afterwards, but it does a really good job of cleaning them out. Might be worth a try, I would.

[TheAbe]

Some fun suggestions coming in. Exactly what I was looking for. At this point, these barrels aren’t so much blue as brown... I’ll look at transmission fluid first, then patched and even cleaning polish embedded boolits.

[LAGS]

I had a Lee Enfield that keyholed no matter what I shot or at any distance.
I soaked the bore with Vinegar for several days.
That was to loosen up any rust.
Then I soaked the bore several times over a week with Ammonia to remove the copper fouling.
Then I soaked the bore with ATF for several days.
I lapped the bore by hand with a tool made out of epoxy and an old cleaning brush.
After all that work , it started shooting way better.
The slugs that shot the best were lead Boolits.
They were heavy weights, cast with very hard lead.
And sized to fit very snug to the bore diameter.
The powder loads were not that hot of a load and I used slower burning powder and kept the speed down under 1200 fps.
Light Boolits still keyholed as did jacketed bullets at higher speeds.

[TheAbe]

I think the KNIL will be the first project, both because it’s shorter and because it’s worse... here is a rough photo of what I’m starting with for the interior of the barrel.
319462

[zymguy]

I’ll try everything else I can first, if for no other reason than the experience. The KNIL may have some muzzle erosion issues, so I’ll look into counterboring.
If this does become my eventual solution, where can one go to get a new barrel made to the appropriate patterns of these rifles? I’d save up and put the money in if I could get something made that would be the right profile externally and would be cut to accept standard .264” projectiles intended for modern (and old) 6.5mm cartridges.

What are your goals for the rifles , I don't know your rifles but i think the 91 is a small ring Mauser. That means that a take off savage barrel in 6.5 Creedmoor which are cheap and easy to obtain could be cut with a new tenon and chambered in your 6.5 Probably not enough there to replicate the military barrel but itd get you shooting. For more dough you can probably find a military style correct pre fit.

[M-Tecs]

I’ll ask around a couple of long-time shops in the area to see who would recommend a smith. Unless anyone here has recommendations for a good smith in the Twin Cities, MN area?

You have a couple of issues for barrel replacement. First the Dutch Mannlicher M95 KNIL carbine and an M91 Carcano long rifle are not commonly rebarreled. That limits your cost effective options. Replacement barrels sources are basically limited to eBay or a custom from a blank. From eBay condition and headspace could be an issue. From a blank the cost will exceed the value of the rifles unless they have significant sentimental value.

If they were Mauser based, you would have lots of options for lower cast short chambered or pre-fits.

[M-Tecs]

What are your goals for the rifles , I don't know your rifles but i think the 91 is a small ring Mauser. That means that a take off savage barrel in 6.5 Creedmoor which are cheap and easy to obtain could be cut with a new tenon and chambered in your 6.5 Probably not enough there to replicate the military barrel but itd get you shooting. For more dough you can probably find a military style correct pre fit.

Per the Frank de Haas book "BOLT ACTION RIFLES". the Italian Carcano M91 shank is .805 long including .050 unthreaded dia .968 at the rear, outside diameter of threads 1.065 with "approx 14 V threads per inch".

[hoodat]

I've got a few that were pretty crusty, and I used strands from a Frontier 45 scrubby, wound around a bronze brush with PB Blaster. (Kroil would prolly be better). I kept at it, because there was nothing to lose, and pretty soon I was convinced that the corrosion was gone. The rifling doesn't look great, but there is plenty of it there, and both rifles shoot pretty darned good, and no key holing. One is a K98 Mauser, the other a sporterized Enfield two groove. I've since shot plenty of cast and jacketed through both of them. jd

[Photog]

Both barrels slug at .267”
your minimum size is going to be .268" and the carcano is gain or progressive twist, made specifically for a LONG jacket bullet. Without the long boolit, you jump a huge gap at the throat, and cast boolits strip the rifling due to the gain twist. IMO its a lost cause to try anything other than factory style loads.

[zymguy]

Per the Frank de Haas book "BOLT ACTION RIFLES". the Italian Carcano M91 shank is .805 long including .050 unthreaded dia .968 at the rear, outside diameter of threads 1.065 with "approx 14 V threads per inch".

sounds like the savage would be .010 too small then, bummer

[TheAbe]

My intent is to keep the original chamberings. Approximately how much does a custom-profile new barrel cost these days? The most cost-effective solution would probably be for me to find a barreled receiver with a good bore. I’ve seen those floating around for Carcanos, but not KNIL carbines. In the meantime, I’m going to experiment with the suggestions here and see what impact each process has. I’ll post results here with before/after photos, though it’s going to take me a while to actually test shooting results.

[Scrounge]

There might be other posts on this topic, and surely on the subtopics it will involve, but how does one go about improving the performance of old military rifle barrels?

I have an Dutch M95 KNIL carbine and an M91 Carcano long rifle that both fail to stabilize their respective bullets the majority of the time at 25 and 50 yards. Targets have bullet-shaped holes instead of round holes in them. Both barrels slug at .267” and I’ve tried nominally .263”, .265” and .268” jacketed bullets, with no noted improvement. The KNIL has dark, worn grooves with a fair bit of pitting, while the M91 has stronger rifling, but also a fair bit of pitting.

Between re-crowning, fire-lapping, and other processes, what steps would others suggest I take and in what order, to attempt to get these rifle barrels serviceable again?

See if you can lay hands on a .269" boolit. My Lyman's #3 Says that most casters & shooters think .002" oversize is the largest you should go, so it should be safe if your barrel is reasonably consistent the whole way down. Of course, if it won't chamber properly, DO NOT shoot it. If the barrel has been slugged properly, and it chambers, 5 or 10 rounds downrange should tell it if it's worth the effort. You might also try a paper patched bullet or boolit. I'm told Zigzag cigarette papers are .001" thick. Machinists use it for checking clearances.

I have a 91/30 Mosin, for which the nominal groove diameter is .311, bore is supposedly .314. Factory ammo will not print on a 100 yard target except by accident. It does pretty well with .316 cast boolits.

Bill

[elmacgyver0]

When you finally give up on those barrels, try one more thing.
Wrap some scotch bright around a bore brush, wet it and sprinkle some scouring powder like Comet or Ajax on it and go to work on those bores.
Stainless steel scour pad material used the same way also works well.
You will be surprised on the gunk that will come out of those barrels.
Will they shoot better, maybe, but you will never know until you try.

[ascast]

I have a few old black cartridge guns that are very sewer pipe like, but rifling still shows. With a cast bullit 2 to 3 or even 4 thousands over groove dia they seem to shoot much better. My Stevens 32-40 will print about 1 1 1/2 inch at 90 yds. with black or pistol powder. The crowns can be checked by doing a "chamber cast" of the first few inches. (open breach to drive it out?). I have done this also with a Bannerman Trapdoor that (like new) was a junk shooter to now hitting rams all day. Cleaning rod damage. Bored out about two inches. ave a side hammer Peabody that somehow got a horrendous ding right on the crown. That got a trim and now shoots well. Problem with counter bore is you need a good spot back there to bore to. good luck

[TheAbe]

If nothing else, I’ll end up with a couple of shiny, of ineffective bores.
How does one make a chamber cast? Just push some soft lead into the muzzle, then push out to look at the shape? Sounds like I need to invest in some low-temperature melting slugging material.

[Bent Ramrod]

Bores that are dark and even speckly or have a few pits will still usually deliver at least halfway decent practical accuracy. But what is fatal is a barrel that has been converted into a blunderbuss by cleaning rod wear at the muzzle.

Tap one of your bore measuring slugs about 1/2” into the muzzle, push it out from the breech, and compare the measurement to the one(s) you pushed all the way through. If it’s any larger, the barrel will never shoot. Cutting it off ahead of the damage at the end and repositioning the sight might help, if you have the capability.

[elmacgyver0]

If nothing else, I’ll end up with a couple of shiny, of ineffective bores.
How does one make a chamber cast? Just push some soft lead into the muzzle, then push out to look at the shape? Sounds like I need to invest in some low-temperature melting slugging material.
You may indeed.
What I suggested is a very last-ditch effort, prior to rebarreling and you can still reline if it doesn't work out.
At that point you do not have anything to lose.

[M-Tecs]

My intent is to keep the original chamberings. Approximately how much does a custom-profile new barrel cost these days? The most cost-effective solution would probably be for me to find a barreled receiver with a good bore. I’ve seen those floating around for Carcanos, but not KNIL carbines. In the meantime, I’m going to experiment with the suggestions here and see what impact each process has. I’ll post results here with before/after photos, though it’s going to take me a while to actually test shooting results.

You will be lucky to find a contoured and threaded unchambered or short chambered barrel for under $250. Since these are not commonly rebarreled chances are you will have to go custom all the way. If that is the case $500 is a starting point.

https://www.fieldandstream.com/guns/rifle-barrel-makers/

[john.k]

A takeoff Mauser 98 barrel is easily fitted to a Mannlicher ...........even a beginner can reduce the thread the few thou with a hand chaser .........however ,the 95 is one of those guns with a fully supported cartridge ,so the barrel has to 'clock' with extractor and ejector recesses.........IMHO ,the Mannlicher action is a klunker ,and not worth time or money ..........get a 98 Mauser.

[nekshot]

Slow down fps and try paper patching. At this point any thing is worth trying if safe!

[Good Cheer]

For a Dutch '95 with badly corroded rifling I did extensive work to try to recondition the bore and finally concluded that nope, it was a lost cause with either lubed lead or paper patched. I really like the piece otherwise so my plan was to have it rebored to .338" and the chamber neck diameter and length enlarged to suit. Brass of course would be formed and fire formed to suit, eventually having a full length sizing die. I discussed the job with a person who had done reboring for me previously and we were good to go, him suggesting that .358" would work as well though I was hesitant due to the lesser wall thickness. I got everything together, got my molds, got the dies worked out. Then again tried to contact the person before sending him the '95. No response. Tried leaving phone messages and received no responses. Not knowing what to think at that point and becoming concerned, I sent a letter with a self addressed stamped envelope. In return the person scribbled a terse don't want your project. Well, that killed my project and I was out the monies involved. I'm stuck with it so perhaps the '95 will make a nice floor lamp.

[Dusty Bannister]

Not the expert here, but the use of various mild acids to remove jacketed fouling in old military rifles might not be the best idea. It will only deepen the pits and may not solve the build up of copper fouling. One might consider the use of Hoppe's bore solvent and repeated brush and soak cycles over a period of time. Swab to wet the bore, scrub with a good Bronze brush to loosen fouling, wipe with dry patch, swab with wet patch and let sit several hours. The SS brushes are so hard that you will just etch the barrel surface where the bronze brush will just scrub and loosen the rust and copper fouling. It might take wearing out two brushes to get the job done and down to bare metal. It has taken years of incomplete cleaning and building up in layers to allow the bore condition to get to this point so expect to take some time to get it cleaned up again. There have been a lot of suggestions as how to clean the bore, pick one and see if you can get a clean bore and improve the way it shoots.

[schutzen-jager]

a few years back i purchased Remington 510 barreled receiver that was damaged by sea water from hurricane Sandy - i purchased it for the receiver, which cleaned up with some filing + polishing - the bore was dark + no rifling visible let it set in scrap pile for months - one boring day i plugged it for the white vinegar treatment - after 3 days now can see rifling + it looks like it might be very shootable -

[ascast]

If nothing else, I’ll end up with a couple of shiny, of ineffective bores.
How does one make a chamber cast? Just push some soft lead into the muzzle, then push out to look at the shape? Sounds like I need to invest in some low-temperature melting slugging material.

yes. but I use a hunk of aluminum foil, just a wadded up ball, snug is good. Get an inch or two into barrel so whole throat, lead, area is captured. Same can be done on the front end ( muzzle) Cerosafe can be reused and it melts around 150.

[Harter66]

I have a pair of Arisakas a 99 at .3165 and a 38 at .270 for those not aware they have Metford type rifling, just humps and valleys . The 6.5 didn't care much for anything I tried until I tried a 266469 as cast and paper patched .272 . 1.5" at 50 doesn't seem like much but compared to jacketed that was jumping the lands and other softer cast it was a huge improvement. The first load key holed at just 5.5 feet at 25 yd jackets were better at 3.5' at 50 yd. The verdict is still out on the 7.7 but the 8×57 neck die is perfect, just lacking in 8mm bullets and really fat 30/31s .

The Carcano shank is actually larger than the LR Mauser . A 1.128 dia blank doesn't leave much room for a shoulder .

The current bid I have for a Savage prefit from a raw blank I own is $200 to turn , thread , and crown to a #2 contour at 24" from a 25" blank and double action thread length with 6" of .750 at the muzzle end .

Past experiences with Malcolm Ballistic Tool makes it worth every penny to me .

[TheAbe]

More interesting comments and suggestions. Keep them coming!
I’m thinking at this point the Carcano barrel is likely salvageable, because though dark, the rifling is fairly strong. I’ll give it a good cleaning, polishing, crown check, and then try cast boolits.
The Dutch M95 I have less confidence in. Apparently a number of these KNIL carbines were rechambered to .303 British by the Indonesian military in the 50’s, and while I’d be hesitant to go that extreme a change, I had the idea that I could have the barrel re-bored to .270 (.277). If I could find a button combo cutter to 6.8 Western specs (.270 land, .277 grove, 1:8 twist rate), that would likely leave a fresh rifled surface (assuming none of the pits are that deep) and give a twist rate close to the 7.7” twist of the original. I have to form 6.5x53R brass anyway, why not make it a 6.8x53R? I would think I could use the same loading data and get very similar performance to the 6.5x53R cartridge, and being a carbine, the greater surface area of the back of the bullet might yield slightly higher velocities at the end of 18”.
Thoughts? I’ll still try to get this one the best I can with 6.5 first, but it’ll make an additional interesting project...

[725]

+1 for an ammonia treatment to attack copper fouling. Followed by some hand lapping with an abrasive and if you can, shoot some paper patched bullets. I've had success with fire lapping, too. Just go slow. Once the metal is gone, it's gone. My final suggestion is to have Bobby Hoyt do a reline. Not that expensive and it retains the exterior condition & markings. Hoyt relined a 43 Egyptian sewer pipe for me and now it's perfect! Even very close exams can't tell it's a reline.

[TheAbe]

I’ve disassembled the KNIL in preparation for transmission fluid...should get that started tonight...

[zymguy]

What was the accuracy expectation of each of these rifles in their prime ?
What's acceptable to shoot and enjoy ?

[Hannibal]

I'm sure they didn't keyhole at 25 yards for one .....

[Somebody]

Another option to retain the original chambering is to reline the barrel. It can be tricky to find liners that are not .22LR, but they do exist. Bore out, solder/epoxy the liner in place, recrown, and ream the leade.

Is it economical? Absolutely not, but the material cost is cheaper than barrel blanks.

[TheAbe]

What was the accuracy expectation of each of these rifles in their prime ?
What's acceptable to shoot and enjoy ?
For the M95, I’d be ok with 4MOA. I’m thinking if I can get a stable bullet, the accuracy will show itself.
Transmission fluid comes out today...we’ll see how it looks.

[TheAbe]

Before
319735
After
319736
It’s cleaner, shinier...but I’m even more convinced there isn’t any worthwhile rifling remaining. I will test it, but I think this one is heading for a re-sleeve, or rifling button...possibly both. Carcano will be next.

[TheAbe]

Took my Carcano apart today, covered the muzzle, and filled with automatic transmission fluid. Decided to do the same to my Krag while I was at it, since it was already apart.
I think there may be another issue with the Carcano besides the barrel, and that is the receiver. I get the idea it suffered a detonation or over-pressure round at one point, as when I got it the stock was cracked through the receiver, the receiver had a significant gap between it and the stock, and the bolt is very loose in the receiver. How loose? I noticed today that without a round, with the bolt closed I can wiggle the front of the bolt if I push at it, and the handle is loose (significantly) in its channel at all points when unlocked. I’ll check the performance once it goes through a week of AT fluid. I’ll note that spent brass is not noticeably larger than live rounds or spent brass from my other Carcano. Could a deformed receiver cause keyholing, even if the chamber and barrel are fine?

[john.k]

carcano is front locking.....any deformation is more likely from handling ,as in stacking in a big heap for surplus sale......where the stock got cracked ......also consider military rifles are fitted loose to work in mud ,dust ,and sand ........the Italians would have to cope with a lot of sand and dust in North Africa.

[TheAbe]

Here is the Carcano after a week of transmission fluid and a good cleaning. The patches actually come out clean now! It’s better than the KNIL, and has grooves that are more pronounced, even to the muzzle.

As for the lock, yes and the fact it’s front-locking is what has me concerned. I would think being front-locked, the front of the bolt should not move when the bolt is closed and locked, but perhaps that’s just when there isn’t a round chambered. I’ll try it with some empty brass as well.

As for next steps, there does appear to be some pitting and roughness...should I go for some valve grinding paste or perhaps a bit of fire lapping?

320095

[TheAbe]

And instead of the bore, after reading some other threads here, I decided to use the grinding compound just to re-crown the Carcano. I think this will work...
Before:
320518
After:
320519

[TheAbe]

One month later, and I got to the range and tested a few projects including my long Carcano. The results I believe point to the barrel being worn, but capable with the right bullet design, and the crown DID need attention. 24 rounds total, all using .268” PPU bullets.
First 6 were the 139gr FMJ BT’s with an open base. Lots of keyholes here, and the worst indicator was 7 holes in the target with 6 rounds fired. I don’t want to think about how that happened, but the performance makes sense with what I’ve read about the Carcano design for long rifles with gain twist rifling. Rifle was designed to function with obturating bullets, and BT’s do not obturate well.
321728

Next 6 rounds were with the 123gr SP bullet with a flat base. While the holes weren’t all perfectly round, they were almost all perfectly round, and so these were followed by 12 more rounds of the 123gr SP’s. All of these also had almost perfectly round holes. Shots were taken at 30-50 yards indoors. Im thinking these, because of their flat base, did obturate, caught the rifling, and were mostly stabilized. These would probably show even better stabilization at longer distance...I’ll try when I get the chance.
Previously the 123’s performed worse, and I’m thinking this was because the uneven crown was a controlling factor and had a greater impact on the lighter projectiles.
321729

[Jim22]

a few years back i purchased Remington 510 barreled receiver that was damaged by sea water from hurricane Sandy - i purchased it for the receiver, which cleaned up with some filing + polishing - the bore was dark + no rifling visible let it set in scrap pile for months - one boring day i plugged it for the white vinegar treatment - after 3 days now can see rifling + it looks like it might be very shootable -

A detail: Household white vinegar is normally 3% acetic acid. Stronger vinegars are available if you look for them. Up to 30%. Don't know if this will help but maybe.

Jim

[303Guy]

This has been an interesting thread. I have a key-holing rifle. It's a Lee Enfield two-groove with a rager large bore and probably a worn throat. With some loads it would shoot some bullets nose first and some would go sideways. In this case, just reducing the load and using a slower powder did the trick. But what might be of some interest to you folks are the captured bullets. Some would show signs of just skipping the rifling then engaging while others just skipped. Reducing the charge would produce full rifling engagement.

Would you believe that this bore shoots cast? There is actually rifling in there. I fire-lapped out the rust. This is not the rifle in question though. The point is that very bad bores can sometimes still be made to shoot.

https://i.postimg.cc/YqZRKNnK/Rusted-303-bore-007.jpg (https://postimages.org/)

Back to the rifle in question.

These are 150gr Hornady's. The only reason why they hit near nose first is that the catch medium was inches from the muzzle. One can see the bore striations are straight so no spinning at all.
https://i.postimg.cc/6pSJyYPB/DSCF7914-I.jpg (https://postimages.org/)

Here is a bullet that skipped at first then picked up the spin. It shows parallel striations then angled and the rifling grooves can be made out on it. There rifling impression can be made out if one looks carefully but what can't be seen in the photo is that in the rifling impression, the striations are not angled. I should try taking a better zoomed photo of it.
https://i.postimg.cc/SsdgzKKc/DSCF6046.jpg (https://postimages.org/)

174gr fmj BT. These just skipped the rifling. Well actually, one didn't. I'd forgotten about that one.
https://i.postimg.cc/FKLtc0t3/1943-180gr-PPU-BTSP-2.jpg (https://postimages.org/)

This is a 110gr Hornady driven by 35gr H47895. Low pressure as the primer image indicates.

One can clearly see the full rifling impression.
https://i.postimg.cc/tRzKhXcS/DSCF7910.jpg (https://postimages.org/)

What's interesting is that these bullets are very short in a very long throated rifle.

And the range test. I couldn't see the top of the foresight post too well so maybe the group could have been a bit rounder. This is only 25m so not stellar but promising once I've improved the front sight - which I've done but not tested.
https://i.postimg.cc/5y9kPCrP/23-09-10-1943-2-Groove.jpg (https://postimages.org/)

And this is a 150 Hornady driven by a slower and lower pressure powder, BL-C(2). Not only that but it's a .308 bullet in a .305 bore.

https://i.postimg.cc/Dzqjn6kj/150gr-30-40gr-BLC-2.jpg (https://postimages.org/)

Increasing the powder charge by 2 grains from 40 42 gr did this. Still nose first and I think it may have spun up a bit.

https://i.postimg.cc/wvgWvN96/150gr-30-42gr-BLC-2.jpg (https://postimages.org/)

Skidded and keyholed 174gr fmj BT
https://i.postimg.cc/6610sg46/DSCF6080.jpg (https://postimages.org/)

One of these spun up and I'm guessing like the 150gr Hornady above.

This bore does shoot cast with full rifling engagement. It's not a terrible bore, just too large and too much jump for normal j-word loads. I did counter-bore it due to the bore condition near the muzzle.

[john.k]

Probably the safest way to remove bore rust is Evaporust ......Deck cleaner (oxalic acid ) is a lot cheaper and faster ,if you are in a hurry.........I would not use mineral acids ,with the exception of phosphoric acid .....iron buffered phosphoric acid will not dissolve steel ,and also leaves a protective coating......which is of little use in a gun bore..........however ,all that leaves a moonscape where the rust was ......IMHO ,the way to improve rusted bores is to recut to clean metal .........with a bit of fiddling around,its quite possible to recut the rifling ,then ream or hone the bore ......obviously ,it will all be oversize and require custom bullets.

[TheAbe]

Some fascinating information 303Guy. It’s seeming more and more like my next experiments should be with lighter loads, and see what happens. I will also try and get my hands on some 6.5 cast boolits. A lead melter and other equipment are in my near future.

I’m also considering having the KNIL re-chambered to .303 British or wildcatting to .270 Dutch or .280 Dutch. I have heard there is a gentleman by the name of Jom Kolb in my general area who might be willing and skilled to do such a re-chambering. Others have been strongly recommended on this forum, but I’d rather not have to ship anything.

As for evaporust, yes I have a gallon and it’s great stuff. I recently used it to clean up a rusty M1842, and the results were impressive. I think that would be a case where fire-lapping would be helpful after the rust was removed to smoothen the pits and the like, but if the rust wasn’t even it might just make things worse. I will try both lighter loads and patched bullets in the KNIL before re-chambering though.

[TheAbe]

I know it’s not been mentioned much on this thread, but my Krag Barrel seems about hopeless. I re-crowned, cleaned with ATF, and scrubbed, but everything I’ve shot through it so far still keyholes. Took it out with a friend the other night and was shooting loads of ~35gr H380 over .309-sized 311284’s, and this was the result. Friend was a bit shocked. He’d never seen holes so large in a paper target before...incidentally the round holes are from a different gun on the same target.
Any suggestions of what else I might try with my Krag barrel, or what I should attempt to look at?

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