12.7x108mm (R)

[ralfabco]

Ideal barrel length and twist rate.

The caliber is not listed on the CIP table.

The only information I found online, is with Snipex, Zvi, and Zastava Arms.

Yes, it is great that school is out and I have some extra time on my hands.

What is the ideal twist rate for the barrel ?

Thanks for your interest.

ZVI – Products – Sniper Rifle Falcon

Společnost orientovaná na výrobu výrobce zejména středorážových zbraní a munice pro armádu a policii.

www.zvi.cz

Long Range Rifle M12 - Black Spear - Zastava oružje ad

Long Range Rifles M12 Black Spear Description Technical characteristic Images Description New model of long range rifle M12 is designed on the basis of Mauser action. Its purpose is ellimination of various types of targets at large distances, up to 1,800 m, in all environments.Cold forged heavy...

www.zastava-arms.rs

SNIPEX

snipex.com

 

[jasent]

It’s a 50 cal. Proper twist will depend on bullet used.
Barrel length is up to you really

 

[ralfabco]

It’s a 50 cal. Proper twist will depend on bullet used.
Barrel length is up to you really

Hunting cartridge 12,7х108

www.tulammo.ru

I believe this is the only 'normal' off the shelf ammo you can find in the USA ^^.

Magtech may consider importing some ammo later in the year. It is listed in the Brazilian division.

The barrel lengths are listed on the attached websites, from 29" to 39."

 

[THEIS]

Hi,

Magtech is not going to be importing x108 brass into the USA and if they did you would not want to shoot it in anything other than a heavy machine gun.

What action do you intend to put this barrel on? More importantly what stock do you plan on putting the barreled action into?

Sincerely,
Theis

 

[ELR researcher]

Ideal barrel length and twist rate.

The caliber is not listed on the CIP table.

https://bobp.cip-bobp.org/uploads/tdcc/tab-i/12-7-x-108-170419-en.pdf

The only information I found online, is with Snipex, Zvi, and Zastava Arms.

50 BMG | 50 semi-auto | 50 caliber | M18 | 510 DTC | 416 Barrett

Vigilance Rifles M18 Russian 12.7 x 108mm. California legal. Shoots and feels like a .50 caliber, legal most places a .50 caliber may not be. Offered excusively through Vigilance Rifles. Read more about your next rifle here.

www.vigilancerifles.co

Yes, it is great that school is out and I have some extra time on my hands.

What is the ideal twist rate for the barrel ?

Thanks for your interest.

ZVI – Products – Sniper Rifle Falcon

Společnost orientovaná na výrobu výrobce zejména středorážových zbraní a munice pro armádu a policii.

www.zvi.cz

Long Range Rifle M12 - Black Spear - Zastava oružje ad

Long Range Rifles M12 Black Spear Description Technical characteristic Images Description New model of long range rifle M12 is designed on the basis of Mauser action. Its purpose is ellimination of various types of targets at large distances, up to 1,800 m, in all environments.Cold forged heavy...

www.zastava-arms.rs

SNIPEX

snipex.com

 

[jasent]

Rcc would make brass I’d imagine
Pierce 20x would work. Never have found out the max col the 20x can eject for live round.

 

[ralfabco]

Hi,

Magtech is not going to be importing x108 brass into the USA and if they did you would not want to shoot it in anything other than a heavy machine gun.

What action do you intend to put this barrel on? More importantly what stock do you plan on putting the barreled action into?

Sincerely,
Theis

I am talking with Voere Austria. The X5 rifle has a barrel switch system and the bolt face can be changed out.

I believe 1:15 barrel twist is good to go with 680-750 grain ball bullets.

 

[THEIS]

Hi,

Well in that case, lolol...Go with whatever Sven tells you instead of random members here. Most that have never seen a 12.7x108 rifle, lol.

Sincerely,
Theis

 

[ralfabco]

Hi,

Well in that case, lolol...Go with whatever Sven tells you instead of random members here. Most that have never seen a 12.7x108 rifle, lol.

Sincerely,
Theis

You know his first name ? WoW. Small world.

Herr Ruhland asked me for additional information.

 

[ELR researcher]

Rcc would make brass I’d imagine
Pierce 20x would work. Never have found out the max col the 20x can eject for live round.

True, the 20X is a .50 BMG-capable action. However, the CIP rim diameter (R1) max for the .50 BMG is .804, for the Russian its .858. Also, the CIP cartridge OAL (L6) for BMG ammo is 5.45, while the Russian is 5.79 - dimensions where long "after market" bullets are not factored into the numbers.

 

[jasent]

I thought I remember reading the 20x had a 6” oal. I had forgot about the .804 vs .858

 

[ELR researcher]

I thought I remember reading the 20x had a 6” oal. I had forgot about the .804 vs .858

Per CIP, the case is 4.25 long (L3) . If the concern is extracting a loaded round with a very long bullet, simple remove the bold and case as one. From the product page the port is well over 4.25 long. More about the 20X at https://pierceengineeringltd.com/20x-action/

John would likely be willing to open the boltface.

 

[jasent]

That’s what I would do is ask John to open bolt face and not worry about oal
The op’s question was mainly what barrel length which is totally up to the shooter and what twist which is totally up to bullet desired. Figured I’d throw in an action that could work as well with good design imo

 

[Frank Green]

I think the OP and I talked yesterday as well.

For a FYI if I remember correctly the original specs for the 12.7x108 rounds are 8 groove barrels, 1-15.5 twist and the DSHK barrels if I remember correctly are 38.5” finish length. Again if I remember correctly as I had one that was the measurement from breech face to muzzle crown. Doesn’t include the muzzle brake.

The 15 twist will handle any conventional bullets and I’ll say including the Hornady 50bmg Amax match bullet with out any issues. You start shooting some of the new solids/match type bullets of around 800gr. I’d go a little faster on the twist. Won’t hurt ya. We’ve made 13.5 twist barrels for 50BMG and shot awesome.

20 years ago I had a gun and made my own chambering in 14.5 Russian necked down to .50cal. Still have my prototype dummy round that I had the chamber reamer and sizing die reamer made from. That barrel was 52” long and 15 twist. The 750gr Amax bullets with my light load came out at 3100fps.

Later, Frank
Bartlein Barrels

 

[ralfabco]

I think the OP and I talked yesterday as well.

For a FYI if I remember correctly the original specs for the 12.7x108 rounds are 8 groove barrels, 1-15.5 twist and the DSHK barrels if I remember correctly are 38.5” finish length. Again if I remember correctly as I had one that was the measurement from breech face to muzzle crown. Doesn’t include the muzzle brake.

The 15 twist will handle any conventional bullets and I’ll say including the Hornady 50bmg Amax match bullet with out any issues. You start shooting some of the new solids/match type bullets of around 800gr. I’d go a little faster on the twist. Won’t hurt ya. We’ve made 13.5 twist barrels for 50BMG and shot awesome.

20 years ago I had a gun and made my own chambering in 14.5 Russian necked down to .50cal. Still have my prototype dummy round that I had the chamber reamer and sizing die reamer made from. That barrel was 52” long and 15 twist. The 750gr Amax bullets with my light load came out at 3100fps.

Later, Frank
Bartlein Barrels

Frank,

Thank you for taking the time to answer my questions.

Ralph

 

[Frank Green]

Frank,

Thank you for taking the time to answer my questions.

Ralph

Interesting on the CIP spec.....
Bore = .4984"
Groove = .5118"
Groove width = .110"
Twist = 14.96 (I'll call it 15)

Looking up my documents we made test barrels for the 12.7x108 (this was a accuracy test barrels) we we're requested to make...

39.5" finish length
Bore = .4995" +.0005" tolerance
Groove = .5095" +.0005" tolerance
Groove width = .098"
Twist = 15.5

Hmmm....interesting on the changes to the bore and groove size that CIP made? Wonder why? Especially going tighter on the bore to .4984".

Actual bullets/ammo I have the bullets measure .510"

Later, Frank

 

[THEIS]

Hi,

For some old school reading on the x108...

https://apps.dtic.mil/dtic/tr/fulltext/u2/a165896.pdf

These guys were walking around this past Shot Show trying to peddle up 12.7x108 importation business.

https://www.pof.gov.pk/download/POF_Catalogue.pdf

Sincerely,
Theis

 

[Frank Green]

Here a couple of pic's for comparison. The last picture is of a WW2 vintage 50bmg ball round next to a standard 12.7x108 round. I think it is a AP/tracer round if I remember correctly. I'd have to dig out my ammunition identification book to look up if it's a APT or a API round.

In the first picture is a line up .... from left to right....
50bmg ball round, 50bmg w/Hornady Amax bullet, 50BMG w/Barnes 800gr solid bullet, 800gr Barnes and custom 900gr Barnes 50cal bullet (they made me a small batch 20 years ago), then the 12.7x108 Russian (dated 1945. Just below the black painted tip is a faint band of red) and last but not least my prototype round for the 14.5 Russian necked down to 50cal.

 

[badassgunworks]

True, the 20X is a .50 BMG-capable action. However, the CIP rim diameter (R1) max for the .50 BMG is .804, for the Russian its .858. Also, the CIP cartridge OAL (L6) for BMG ammo is 5.45, while the Russian is 5.79 - dimensions where long "after market" bullets are not factored into the numbers.

The pierce 20x will work just fine and the bolt can be made in what ever size wanted we are using to with a .875 diamiter case and the 420 blitzkrieg is 5.923 long and it ejects it just fine. And the tennon is 1.500 16 tpi is its more then big enouch the 458 goliath is .875 in diamiter and it will fit threw the ejection port as well