Building a Hybrid Yugoslav M70B1 from a Stub with Screws

Building a Hybrid Yugoslav M70B1 from a Stub with Screws

Part 7

George Spafford is building a replica of the Yugo M70B rifle using a stub parts kit. A new installment will appear here every Friday

M70 Barrels


Inserting a bullet in the muzzle helps indicate bore condition. In many cases, Yugo


bores are so bad the cartridge will drop in all the way up to the shoulder.

This brings us to the barrels. Another issue I had to confront was the condition of the Yugo bores. I wasn't until the 1980s that Zastava put the chrome plating process for barrels into place. As a result, many of the M70 kits imported into the USA do not have chrome bores, and almost all saw heavy combat use. Because of this, many Yugos have what are called "dark bores" — the bores have been shot out and are so corroded/worn that they literally look black.

To test the bores, people take a 7.62x39 cartridge or just the bullet and see how far it can be inserted into the bore. If it falls down to the shoulder of the cartridge, then the barrel is pretty much a sewer pipe and will more or less shoot like a smoothbore, resulting in fairly poor accuracy — we're talking feet, not inches, at a 100 yards in these cases.


Using CLP's foaming bore cleaner. George applied, soaked, and then removed it

with a patch at least four times combined with a wire brush to scrub the dark bore.

By using CLP's Foaming Bore Brush and bore cleaner plus extensive wire brushing and dozens of patches, I was able to clean up the chamber and bore. After all the crud was gone, I could then test my kits and find which barrel the bullet went down the least meaning it presumably had more rifling.


The kit selected had a barrel where the bullet would only go a little over 3/4 of the way down the length of the bullet itself before stopping. Now, for the sake of argument, if that were my only kit and it failed the bullet test, then I would need to decide whether to change to another surplus barrel, perhaps purchase a new U.S. barrel (and their reputation is spotty), or even just use the worn out Yugo barrel as-is. If you have a fried barrel, you can either use it as-is or at least have potential options.

GET THE NEWSLETTER Join the List and Never Miss a Thing.

Recommended Articles

See More Recommendations

Popular Videos

Shooting the 20mm Lahti

Shooting the 20mm Lahti

David Fortier had the chance to fire the Lahti L-39 while filming the 2018 season of Guns&AmmoTV while on location at DriveTanks.com.

See More Popular Videos

Trending Articles

This will be the first of many investigative reports about the NRA by Firearms News. 2nd Amendment

Firearms News Investigates the NRA: Part 1

Nedd Scott - July 18, 2019

This will be the first of many investigative reports about the NRA by Firearms News.

CRKT makes 17 different knife models exclusively for Ruger, from fixed hunting knives to tactical folders, and many of their models are offered in several different styles. Accessories

Ruger CRKT Knives Review

James Tarr - July 08, 2019

CRKT makes 17 different knife models exclusively for Ruger, from fixed hunting knives to...

No one can restore receptivity to another Trump term with these disaffected gun owners but the president himself. 2nd Amendment

2020 is Trump's to Blow with Gun Owners

David Codrea - July 09, 2019

No one can restore receptivity to another Trump term with these disaffected gun owners but the...

Rhode Islanders are setting brushfires for freedom once again as they advance a Second Amendment Sanctuary Town movement. 2nd Amendment

SPECIAL REPORT: BIG 2A HISTORY BEING MADE IN LITTLE RHODE ISLAND

John Peterson - May 22, 2019

Rhode Islanders are setting brushfires for freedom once again as they advance a Second...

See More Trending Articles

More Gunsmithing

On the bench in front of me was a customer's M&P Shield he'd dropped off complaining about the Gunsmithing

Apex M&P Trigger Kits

Gus Norcross - July 11, 2014

On the bench in front of me was a customer's M&P Shield he'd dropped off complaining about...

Lone Wolf Distributors are now offering the Advantage Arms .22 Conversion Kit for Glock pistols. Gunsmithing

Lone Wolf Advantage Arms .22 Conversion Kit

SGN Online Editors - April 16, 2014

Lone Wolf Distributors are now offering the Advantage Arms .22 Conversion Kit for Glock...

Cerakoting of firearms has become hugely popular, more so for decoration than protection, although the finish does both. Gunsmithing

Cerakote - The Hottest Finish in Firearms

James Tarr - February 14, 2019

Cerakoting of firearms has become hugely popular, more so for decoration than protection,...

AR gas blocks are available in many styles. This article will help you choose the part you need for your build and demonstrate various installation techniques. How-To

How To Install AR Gas Blocks

Gus Norcross - August 05, 2020

AR gas blocks are available in many styles. This article will help you choose the part you...

See More Gunsmithing

GET THE MAGAZINE Subscribe & Save

Digital Now Included!

SUBSCRIBE NOW

Give a Gift   |   Subscriber Services

PREVIEW OUR CURRENT ISSUE

GET THE NEWSLETTER Join the List and Never Miss a Thing.

Get Digital Access.

All Firearms News subscribers now have digital access to their magazine content. This means you have the option to read your magazine on most popular phones and tablets.

To get started, click the link below to visit mymagnow.com and learn how to access your digital magazine.

Get Digital Access

Not a Subscriber?
Subscribe Now