Yugo M48 BO Mauser Rifle Has Very Rough Bore. Is It Safe To Shoot?

[oldgunner]

Today I shot my Yugo M48 BO at a range. It turned out that I overpaid for this military surplus rifle even when the price is $270, with a hard case, and shipping included.
The accuracy is 4 inch at 30 yards.

The ammo I used is PPU Match Line 8 mm Mauser FMJ BT 200 grain / 12.96 gram.

This is really a minute of man rifle at 100 yards!
My shotgun shoots slug with a much better accuracy.
Well, I think that I have just experienced something happened on many battlefields all over the world. Full-caliber cartridges are too powerful for steel that makes most military bolt-action rifles. After a few thousands of rounds fired, rifle barrels will be worn to such extend that accuracy dropped precipitously. Sometimes, the whole army was equipped with these inaccurate rifles. They could only adopt the tactics of ambush and shooting in short distances. When the opponent found covers and started to return fire, these worn-out rifles would not have the accuracy to hit the hidden enemies even in short distance. It was time for these soldiers to throw an avalanche of grenades and launch a bayonets charge. Bayonets is another weapon that is hard to manufacture, hard to repair, and easy to break. Such armies usually did not even have enough working bayonets. That is why many soldiers of these armies will have a big sword on their backs. A bayonets charge was usually a big sword and spears charge.

Maybe you're just a bad shot! (only kidding man)

 

[Qwikdraw45]

What about rebarreling it? If not a surplus barrel, anyone make new barrels that match original military ones?

 

[powerman]

It's to clean, shoot it some more, I bet it will settle down.

 

[easycity]

I should qualify myself when I blamed Yugo M48 BO. In the same range, side by side with this M48, I used a Norinco SKS with iron sight, and shot a pumpkin at 50 yard to pieces. Using a Smith & Wesson 15 22 and the peep sight, I could shot a 3 inch group at 50 yards. That is about 6 MOA.

I am thinking about replace the barrel, either with a M48 8mm mauser barrel, or a 308 Wilson barrel. Anyone know a reputable gunsmith to do this kind of job? cost?

Yugoslavian M48 24/47 K98 mauser 8mm barrel w front & rear sights nice condition, $109
Yugoslavian M48 24/47 K98 mauser 8mm barrel w front & rear sights nice condition | eBay

WILSON ARMS - 98 MAUSER BARREL (Brand New, High Quality, Cartridge: 308 Winchester) $162
https://www.brownells.com/rifle-parts/barrel-parts/rifle-barrels/98-mauser-barrel-prod16633.aspx

BROWNELLS - SHORT CHAMBERED MAUSER BARREL $94
https://www.brownells.com/rifle-par.../short-chambered-mauser-barrel-prod22531.aspx

 

[mac1911]

I should qualify myself when I blamed Yugo M48 BO. In the same range, side by side with this M48, I used a Norinco SKS with iron sight, and shot a pumpkin at 50 yard to pieces. Using a Smith & Wesson 15 22 and the peep sight, I could shot a 3 inch group at 50 yards. That is about 6 MOA.

I am thinking about replace the barrel, either with a M48 8mm mauser barrel, or a 308 Wilson barrel. Anyone know a reputable gunsmith to do this kind of job? cost?

Yugoslavian M48 24/47 K98 mauser 8mm barrel w front & rear sights nice condition, $109
Yugoslavian M48 24/47 K98 mauser 8mm barrel w front & rear sights nice condition | eBay

WILSON ARMS - 98 MAUSER BARREL (Brand New, High Quality, Cartridge: 308 Winchester) $162
https://www.brownells.com/rifle-parts/barrel-parts/rifle-barrels/98-mauser-barrel-prod16633.aspx

BROWNELLS - SHORT CHAMBERED MAUSER BARREL $94
https://www.brownells.com/rifle-par.../short-chambered-mauser-barrel-prod22531.aspx

What makes you think a new barrel will shoot any better.
How tight are the action screws, hows the draw pressure on the barrel. Where you shooting from a bench, supported, sling, prone? How many rounds did you shoot? How certain are you you used the same sight picture.
Try some different ammo. Put about 50 rounds through it before you dismiss it.

How many shots did it take to kill the pumpkin, how big was the pumpkin. Aperture style sights are much more accurate and easier to use.

4" at 30 yards is 12 moa. Not to bad for your first time out with a old rifle. Put it the hands of someone who shoots old iron sight rifles. More so some one who competes in something like cmp vintage military and see what they can do at 100 yards prone supported.

 

[gerrycaruso]

I agree with everything that mac1911 said. Don't be too quick to give up on that old rifle. As I said earlier, I have rifles with bores that look worse than yours that still shoot fine. I'm amazed at the accuracy that's still possible from bores that look hopeless.

 

[mac1911]

I agree with everything that mac1911 said. Don't be too quick to give up on that old rifle. As I said earlier, I have rifles with bores that look worse than yours that still shoot fine. I'm amazed at the accuracy that's still possible from bores that look hopeless.

OP let me know ho much you want for that poor thing. You can find a worse rifle for a wall hanger.

 

[easycity]

I used a 8 mm cartridge and tested the muzzle of this Yugo M48 BO.

Here is the picture of the cartridge itself.

It seems that this M48 is far from being worn out. Can I say that it is not likely to have severe throat erosion?

I also took out the action screws and re-tighten them. What I found is that both of the action screws are easy to unscrew, offering no resistance to my screwdriver. When I re-tighten them, I can only get the rear one very tight. The front one is stuck between two notches. I had to back off a bit, to align the notch to the hole of smaller screw (the locking screw). Then I can screw in the smaller locking screw.

As can be seen from this picture, the big action screw has 3 notches. One of the notches needs to be aligned to the hole of the smaller locking screw.
The front screw is too loose for one notch, but I could not advance to the next notch. So in the finished state, the front action screw is not tightly screwed in.

When I shoot the M48 with horrible accuracy, the two action screws are not tightly secured. Is that the cause of my problem?
Now I tightly secured the rear action screw, and the front action screw is still loose. Does that solve the problem? Is there any way for me to tighten the front action screw?

 

[mac1911]

I used a 8 mm cartridge and tested the muzzle of this Yugo M48 BO.

Here is the picture of the cartridge itself.

It seems that this M48 is far from being worn out. Can I say that it is not likely to have severe throat erosion?

I also took out the action screws and re-tighten them. What I found is that both of the action screws are easy to unscrew, offering no resistance to my screwdriver. When I re-tighten them, I can only get the rear one very tight. The front one is stuck between two notches. I had to back off a bit, to align the notch to the hole of smaller screw (the locking screw). Then I can screw in the smaller locking screw.

As can be seen from this picture, the big action screw has 3 notches. One of the notches needs to be aligned to the hole of the smaller locking screw.
The front screw is too loose for one notch, but I could not advance to the next notch. So in the finished state, the front action screw is not tightly screwed in.

When I shoot the M48 with horrible accuracy, the two action screws are not tightly secured. Is that the cause of my problem?
Now I tightly secured the rear action screw, and the front action screw is still loose. Does that solve the problem? Is there any way for me to tighten the front action screw?

Yes loose screws can be a problem, not being able to turn the screw to next alignment not so much. These screws where install many years ago and the wood had most likely compressed.
Do a google search on restoring accuracy to Russian captured K98s it will help.

Also try some 150 grain ammo if you can find some.
For starters I would tighten both screws to about 35inchlbs and shoot it some more

How’s the trigger usually they are pretty good for surplus rifles. By your own admission skill I think you just need to get comfortable behind the yugo. Get you sight focus and alignment in check, breath and let the trigger. Break on it’s own.

 

[easycity]

Thanks for the advice of searching for restoring accuracy to Russian-captured Mauser.
I will try to get tin foil under the screws and tighten the screws to 35 inch lbs. Since the screws are flat head screws, 35 inch lbs will feel very tight from a flat head screw driver.
When I first shot the Yugo M48 to the accuracy of 4 inches at 30 yards, both action screws were loose, and offered no resistance to screw driver. That may explain most of the problem.
The ammo I used is 200 grain. It may be too heavy for pitted rifling to stabilize. I will try to find 150 grain ammo.
The trigger of my M48 is very good, smooth, crisp, about 7 pound.

This is the picture of the crown, already posted in the first message of this thread:

Can we rule out the problem at the crown?

 

[Jason m]

Someone needs to Photoshop those bore pics with a James Bomd figure in them, other than that I got nothing.

Jason

 

[mac1911]

Thanks for the advice of searching for restoring accuracy to Russian-captured Mauser.
I will try to get tin foil under the screws and tighten the screws to 35 inch lbs. Since the screws are flat head screws, 35 inch lbs will feel very tight from a flat head screw driver.
When I first shot the Yugo M48 to the accuracy of 4 inches at 30 yards, both action screws were loose, and offered no resistance to screw driver. That may explain most of the problem.
The ammo I used is 200 grain. It may be too heavy for pitted rifling to stabilize. I will try to find 150 grain ammo.
The trigger of my M48 is very good, smooth, crisp, about 7 pound.

This is the picture of the crown, already posted in the first message of this thread:

Can we rule out the problem at the crown?

You can still see the groves and lands in that pic. I have rifles that are well worn and will swallow a bullet right to the neck and still shoot 4mao with out much effort.
On the flip side i had a M1 garand gauge 1 and 1 on muzzle and throat and holding the 8 ring was work!

What i would do is forget putting any foil under the action. Its only going to mess with the bedding.
Loosen screws again and then snug them thumb tight now bump the butt of rifle on the ground on a folded towel or rug.
now after the 2nd or 3rd thump leave the butt on the ground and tighten th e action screws. This will get the action seated up against the recoil lug. This is also the time where a torgue screw driver comes in handy even a cheap on will do.
35 inch pounds should not really feel tight even with a flat blade head. If your just using a screw driver try 2 fingers and a thumb over the top of th e handle. Like a claw lifting the drive from the handle vertically.
Then shoot it. Give it 10 rounds to settle in and season the bore.
Try this at 50 yards place as many 3" black bulls about 8" appart on center as you can fit on your backer. Shoot 2 rounds at each dot. Keep shooting 2 shots per bull until you see any changes.

 

[easycity]

I would like to report the latest progress on my Yugoslavian Mauser M48 BO.
With the advice given by so many experts here, I tightened the action screws, and practiced more, trying to improve my shooting skills. Recently I acquired some no-brand Russian-made 8mm Mauser ammo, at the price of 45 cents per round from fedarm.com.
This type of ammo is also available from GunBroker.
I shot more than 20 rounds yesterday. Not only is this ammo safe, it is a superb match for my M48.
With iron sight, simple Caldwell rest at the front, DIY rest at rear (rice in shopping bad in plastic lunch bag), I put 5 rounds within 1.3 inches at 50 meters, equivalent to 2.5 MOA. I was overjoy by such result from a dark-bore M48.

Thanks for everyone who helped!

 

[mac1911]

I would like to report the latest progress on my Yugoslavian Mauser M48 BO.
With the advice given by so many experts here, I tightened the action screws, and practiced more, trying to improve my shooting skills. Recently I acquired some no-brand Russian-made 8mm Mauser ammo, at the price of 45 cents per round from fedarm.com.
This type of ammo is also available from GunBroker.
I shot more than 20 rounds yesterday. Not only is this ammo safe, it is a superb match for my M48.
With iron sight, simple Caldwell rest at the front, DIY rest at rear (rice in shopping bad in plastic lunch bag), I put 5 rounds within 1.3 inches at 50 meters, equivalent to 2.5 MOA. I was overjoy by such result from a dark-bore M48.

Thanks for everyone who helped!

Awesome, thanks for the follow up

 

[daekken]

Nice. One thing to remember with milsurps is that even a for a military M16 - a "good example" is 2 MOA. The AK is about 4 MOA, SKS 3 MOA, etc.

That's plenty accurate for most people, and certainly the battlefield.

The "1 MOA" or "sub-MOA" stuff I think gets a bit overblown. Everyone likes accurate rifles, but for every 100 "this is a sub-MOA gun" comments at the range or posts on the web I see maybe a handful of shooters that can really do it on a target...I guess those sub-MOA shooters never actually go to the range and just stick to the internet.

 

[Uzi2]

I had a Mauser that had a bore that looked like that. I cleaned it real well and it shot fine.

 

[mac1911]

Nice. One thing to remember with milsurps is that even a for a military M16 - a "good example" is 2 MOA. The AK is about 4 MOA, SKS 3 MOA, etc.

That's plenty accurate for most people, and certainly the battlefield.

The "1 MOA" or "sub-MOA" stuff I think gets a bit overblown. Everyone likes accurate rifles, but for every 100 "this is a sub-MOA gun" comments at the range or posts on the web I see maybe a handful of shooters that can really do it on a target...I guess those sub-MOA shooters never actually go to the range and just stick to the internet.

There not showing up at the Nationals/CMP games either.

the accuracy requirements for military rifles and ammo is not a very high standard anyhow 4-6 moa was/is plenty vood enough for general issue.