Cosmoline
Member
I'm not sure what you mean. .308" is .308" everywhere. The bore of Russian and Soviet arms date back to the old "three line" measurement which is about .311"
Domestic 7.62x39 .308 bullets rifles and ammo fact or myth?
- Thread starter R.W.Dale
- Start date
- Status
Ed Harris (Ruger Engineer) respondsre minio 30 bbls
--- Ed Harris <ke4sky@x*yz.net> wrote:
When I was at Ruger the Mini Thirty barrels were made from the same blanks and using the same tools as standard .30 cal. barrels, but were selected among those towards the maximum allowable tolerance for a normal .30 or "slightly" oversized. Nominal .30 cal. specs are .300 bore and .308 groove + 0.0015 - 0.0000,
whereas the Mini Thirty is .301 bore and .309 groove + 0.0015 - 0.0000, so you see there is overlap. Twist is 10 inches per turn.
For a custom 7.62x39 to give best accuracy with standard weight bullets from 110-150 grains use a normal .300x.308 one turn in 14 inches. That's what my Sako AII has and it drives nails.
Ed Harris
--- Ed Harris <ke4sky@x*yz.net> wrote:
When I was at Ruger the Mini Thirty barrels were made from the same blanks and using the same tools as standard .30 cal. barrels, but were selected among those towards the maximum allowable tolerance for a normal .30 or "slightly" oversized. Nominal .30 cal. specs are .300 bore and .308 groove + 0.0015 - 0.0000,
whereas the Mini Thirty is .301 bore and .309 groove + 0.0015 - 0.0000, so you see there is overlap. Twist is 10 inches per turn.
For a custom 7.62x39 to give best accuracy with standard weight bullets from 110-150 grains use a normal .300x.308 one turn in 14 inches. That's what my Sako AII has and it drives nails.
Ed Harris
jerkface11
Member
Corriea I think it was about 100 fps. Krochus should be back tomorrow so he'll probably post pictures of the groups and everything for you.
R.W.Dale
Member
A little less than 100 FPS with this load, With more potent loadings the velocity diffrence is less
rangerruck
Member
you are right, amer ammo is typically 308 as well as the bbls, whereas everything else made everywhere else is 310 or 311. Ant that includes cz's, such as mine! it is a one hole punch with foreign stuff, but not with american ammo.
More Ruger Bbl info from Ed Harris (formerly of Ruger)
-- Ed Harris <ke4sky@xy*z.net> wrote:
During the development of the Ruger Mini Thirty the chamber we used
was derived from prints provided by the Lapua Cartridge Factory in
Finland which made our proof ammunition. JGS has these prints and
can provide tools under the designator 7.62x39 LAPUA. This is very
similar to the CIP (equivalent of SAAMI in the EU), but held towards
the minimum tolerance. Ball seat diameter is 0.3114" with a Mauser-
style long gradual forcing cone of about 1 degree included angle,
with no cylindrical ball seat.
The SAAMI print which was standardized is derived from the CIP and
uses the gradual angle to mitigate excessive chamber pressures if European
ammunition with bullet diameters of up to .311" is used in American
barrels with .308" groove diameters. Reducing barrel groove diameter
from .310 to .308 does raise pressure slightly, by about 5,000 cup,
but remains well under 50,000 cup within the design limits of modern
rifles.
The Lee and NEI bullets which i designed for the 7.62x39 were
developed to fit the CIP-SAAMI-LAPUA type chambers, but NOT the
Chinese ones!
The SAAMI-CIP is quite different from the chambers used in Chinese AK
andSKS rifles. These have no cylindrical ball seat at all, but simply an
angle taken from the .336" neck diameter with a very long neck, like a
WWII .303 British "trench chamber." Not conducive to best accuracy.
USSR, Yugo and East German SKS rifles have chambers which more closely
resemble the CIP.
Ed Harris <ke4sky@xy*z.net>
in C-B-L Paladin wrote
I have a Ruger Model 77 in 7.62x39mm. I'm under the impression
from information published when the rifle came out that the bore has
nominal 308" grooves but a very long throat which allows the
military surplus .310" bullets to "swage down" for passage.
Would you care to comment on any aspect(s) of this, especially
as it relates to cast bullet selection(s)???
********************
-- Ed Harris <ke4sky@xy*z.net> wrote:
During the development of the Ruger Mini Thirty the chamber we used
was derived from prints provided by the Lapua Cartridge Factory in
Finland which made our proof ammunition. JGS has these prints and
can provide tools under the designator 7.62x39 LAPUA. This is very
similar to the CIP (equivalent of SAAMI in the EU), but held towards
the minimum tolerance. Ball seat diameter is 0.3114" with a Mauser-
style long gradual forcing cone of about 1 degree included angle,
with no cylindrical ball seat.
The SAAMI print which was standardized is derived from the CIP and
uses the gradual angle to mitigate excessive chamber pressures if European
ammunition with bullet diameters of up to .311" is used in American
barrels with .308" groove diameters. Reducing barrel groove diameter
from .310 to .308 does raise pressure slightly, by about 5,000 cup,
but remains well under 50,000 cup within the design limits of modern
rifles.
The Lee and NEI bullets which i designed for the 7.62x39 were
developed to fit the CIP-SAAMI-LAPUA type chambers, but NOT the
Chinese ones!
The SAAMI-CIP is quite different from the chambers used in Chinese AK
andSKS rifles. These have no cylindrical ball seat at all, but simply an
angle taken from the .336" neck diameter with a very long neck, like a
WWII .303 British "trench chamber." Not conducive to best accuracy.
USSR, Yugo and East German SKS rifles have chambers which more closely
resemble the CIP.
Ed Harris <ke4sky@xy*z.net>
in C-B-L Paladin wrote
I have a Ruger Model 77 in 7.62x39mm. I'm under the impression
from information published when the rifle came out that the bore has
nominal 308" grooves but a very long throat which allows the
military surplus .310" bullets to "swage down" for passage.
Would you care to comment on any aspect(s) of this, especially
as it relates to cast bullet selection(s)???
********************
jerkface11
Member
Rangerruck you're mistaken. American made 7.62x39 uses .311 bullets. It shoots like crap for other reasons.
American made 7.62 x 39 W/W white box?
A cant document it, but it is widely known in my circles, includng a European Firearms dealer, that Sellier & Bellot makes a LOT of the WW white box pistol Ammo. I know fer sure the W/W 7.62 x 25 is S & B
I DO hope that Yugoslavia's (or is it now SERBIA?) Privi Partisan's manufacturer (Manufacturer of WOLFE GOLD) makes W/W 7.62 x 39 white box, but I doubt it.
Privi is high quality, reloadable, VERY pretty, resembles Lapua brass, and their corrollary WOLFE gold product appears excellent to but it aint cheap...almost $10.00 a box.
Century sometimes offers Privi under their house brand (HOTSHOT) for $6.95 a box.
I reload my own gas checked 7.62 x 39 for 'bout $13.00/C with my own cast bullets.
yodar
A cant document it, but it is widely known in my circles, includng a European Firearms dealer, that Sellier & Bellot makes a LOT of the WW white box pistol Ammo. I know fer sure the W/W 7.62 x 25 is S & B
I DO hope that Yugoslavia's (or is it now SERBIA?) Privi Partisan's manufacturer (Manufacturer of WOLFE GOLD) makes W/W 7.62 x 39 white box, but I doubt it.
Privi is high quality, reloadable, VERY pretty, resembles Lapua brass, and their corrollary WOLFE gold product appears excellent to but it aint cheap...almost $10.00 a box.
Century sometimes offers Privi under their house brand (HOTSHOT) for $6.95 a box.
I reload my own gas checked 7.62 x 39 for 'bout $13.00/C with my own cast bullets.
yodar
R.W.Dale
Member
I would like to bump this topic in hopes of gaining more info.
Join the curio & relics news list and you will have my source, about 800 BATF licenced 01 and 03 collectors whot shoot and reload military rifles
Undocumented source, I was a vendor of QC/Inspection instruments to Olin Brass, a W/W cartridge-ammunition manufacturer in East Alton Illinois, where years ago I heard that informal talks with European Manufacturers was in consideration
I have been collecting and reloading since 1964
C-R-FFL mailing list - [email protected]
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Undocumented source, I was a vendor of QC/Inspection instruments to Olin Brass, a W/W cartridge-ammunition manufacturer in East Alton Illinois, where years ago I heard that informal talks with European Manufacturers was in consideration
I have been collecting and reloading since 1964
C-R-FFL mailing list - [email protected]
Subscription options:
http://lists.crufflecarp.com/mailman/listinfo/c-r-ffl
Interesting.
I'm curious where RangerRuck got his information from. This is factory Winchester 123gr FMJ ammo.
Somebody asked me if I was certain that it was .310-.311" bullet diameter, and that I hadn't measured it wrong.
The component Winchester bullets I buy in bulk mike the same .311".
I'm curious where RangerRuck got his information from. This is factory Winchester 123gr FMJ ammo.
Somebody asked me if I was certain that it was .310-.311" bullet diameter, and that I hadn't measured it wrong.
The component Winchester bullets I buy in bulk mike the same .311".
R.W.Dale
Member
Gewehr98 Thanks, that's the kind of hard evidence I'm lookin for. As the saying goes "a picture is worth a thousand words"
R.W.Dale
Member
Another bump in hopes of adding more useful info.
chris in va
Member
I read the whole thread. Now if US ammo is 311 and my CZ's bore is 311, why do people say it shoots worse than Wolf, etc? I haven't tried it, just curious as I may be hunting with it this year.
R.W.Dale
Member
My guess it that the domestics inaccuracy stems from inconcinstities other than the bullet diameter. The absolute worst "groups' fired from my little CZ carbine was with remington 7.62x39 we're talking 10" at 100 yds. whatever you do don't try to hunt with this ammo if your rifle shoots it as badly as mine does.
Harley Quinn
Member
Typically in small firearms, the diameter of the bullet matches the diameter of the circle that encompasses the bottoms of the rifled grooves, the groove diameter. The bore diameter is the measure across the tops of the lands. When the cartridge is fired, the bullet is forced into the barrel and the rifling engages the bullet, engraving it with an impression of the rifling. As the bullet is propelled down the barrel, it begins to spin. This rate of spin is dictated by a bullet's muzzle velocity and the twist rate of the rifling. As mentioned earlier, for a given caliber, faster rates of twist are needed to stabilize longer bullets.
Bullets fired from a rifled barrel should ideally be at or slightly under the groove diameter, and definitely larger than the bore diameter. A bullet that is too large will have to swage down to fit in the bore, which can cause excessive pressures, while a bullet that is too small will either leak gas or obturate at an angle, both of which will provide poor accuracy
Bullets fired from a rifled barrel should ideally be at or slightly under the groove diameter, and definitely larger than the bore diameter. A bullet that is too large will have to swage down to fit in the bore, which can cause excessive pressures, while a bullet that is too small will either leak gas or obturate at an angle, both of which will provide poor accuracy
chris in va
Member
Alright, so bottom line...what is the most accurate commercial HP/SP ammo I can buy for my CZ carbine?
R.W.Dale
Member
The best FACTORY ammo I've fired in my CZ is the Wolf 154grn SP This ammo is fast 2200fps from my cz, Accurate (for factory ammo) 2 to 3 MOA and by all accounts hits deer hard.
http://www.brassfetcher.com/7.62x39mm Wolf 154gr Soft Point.html
This ammo is so good it's caused me to give up on trying to beat it's velocity with 150grn handloads. I can far surpass it's accuracy but not it's power the best I can do with 150 grn handloads is 2050 fps
chris in va
Member
Thanks Krochus, I'll have to pick some of that up. Have some S&B softpoint right now but haven't tried it yet.
R.W.Dale
Member
I have yet to shoot any S&B x39 but if it's anything like their x54r loading it should be excellent ammo.
S & B 7.62 x 39
It's almost as good as Privi Partisan
S & B is fine ammo
I cast my own and at 100 yards, my handloads hit a 3" target spinner on good days and a 5" spinner routinely Lee 155 2R mould of antimony enhanced with tin wheelweight metal
yodar
It's almost as good as Privi Partisan
S & B is fine ammo
I cast my own and at 100 yards, my handloads hit a 3" target spinner on good days and a 5" spinner routinely Lee 155 2R mould of antimony enhanced with tin wheelweight metal
yodar
Harley Quinn
Member
Hi yodar,
Regarding your cast bullet: Do you get much lead build up?
What are your specs (fps) loads (powder etc.)? overall length of the bullet and the twist of the shooter?
Thanks
Regarding your cast bullet: Do you get much lead build up?
What are your specs (fps) loads (powder etc.)? overall length of the bullet and the twist of the shooter?
Thanks
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