.30 Carbine Blackhawk v. .327 Fed Mag Blackhawk

[jski]

In the end gentleman, I think the guys at Real Guns, in their article Ruger's 30 Carbine Blackhawk, got it right:

The 30 Caliber carbine holds only 2 grain more powder than the diminutive 327 Federal Magnum and 4 grains less than the mundane 357 Magnum. However, seat typical bullets in all three and the long overall length and long cylindered .30 Carbine has a net capacity 2 1/2 time greater than the 327 Federal magnum and only half a grain less than the ubiquitous 357 Magnum. The 30 Carbine also packs more pressure than the other two rounds with 46.4k psi, compared to 44.9k psi for the 327 Fed Mag and 35.0k psi for the 357 Magnum. If the 30 Carbine poses a challenge, it is identifying a powder that will burn efficiently within a revolver's relatively small bore volume; at equal 7.5" barrel lengths expressed in cubic inches of volume: 30 Carbine 0.559, 327 Fed Mag 0.630, 357 Magnum 0.751.

The 30 Carbine version [of the Blackhawk] has a different feel, shooting with close to rifle accuracy, probably better than M1 Carbine accuracy.

 

[eldon519]

Not as right as you might think, he definitely gets the pressures wrong. .30 Carbine MAP is 40kpsi. .327 MAP is 45kpsi. I'm very skeptical of the 2.5 net volume claim. A bit disappointing, I really like Real Guns.

He's also saying that the .30 carbine struggles to effeciently burn all that powder in such a small volume. That problem is exacerbated by the lower MAP of the .30 carbine. But you can always load a .327 long too if the platform allows for it, and then you have the benefit of the increased powder volume and the increased pressure limit to take advantage of it.

http://www.saami.org/specifications_and_information/specifications/Velocity_Pressure_CfR.pdf

http://www.saami.org/specifications_and_information/specifications/Velocity_Pressure_CfPR.pdf

 

[jski]

I noticed that too. He seems to get the .357 and .327 mags correct:

The 30 Carbine also packs more pressure than the other two rounds with 46.4k psi, compared to 44.9k psi for the 327 Fed Mag and 35.0k psi for the 357 Magnum.

So I wonder where he's getting the 46.4k psi figure for the .30 Carbine?

I too have always found Real Guns to be a quality site.

 

[Ed Ames]

I noticed that too. He seems to get the .357 and .327 mags correct:


So I wonder where he's getting the 46.4k psi figure for the .30 Carbine?

I would ask the author...you may save someone from a bad day. From what I've read the original high pressure test loads were 47.5k so loading to 46.4k seems imprudent.

 

[CraigC]

Real Guns is one guy and his wife. He's an arrogant hack that runs a gun shop and writes articles. When he gets his facts wrong, he will argue, deflect and ultimately drag the messengers name through the mud.

 

[eldon519]

Real Guns is one guy and his wife. He's an arrogant hack that runs a gun shop and writes articles. When he gets his facts wrong, he will argue, deflect and ultimately drag the messengers name through the mud.

I had forgotten that there were issues along those lines, but I do recall that now that you mention it. Perhaps best not to take everything he says as gospel, but I do appreciate that he often posts lots of chrono results for a wide variety of handloads.

 

[jski]

I sent the editor of Real Guns:

In your article you stated: "The 30 Carbine also packs more pressure than the other two rounds with 46.4k psi, compared to 44.9k psi for the 327 Fed Mag and 35.0k psi for the 357 Magnum."

The figures look correct for the .357 and .327 mags. but the SAAMI spec for the .30 Carbine is 40K psi. Is there another source you used?

The was the response:

Yes. The 46.4 kpsi is the current CIP Ptmax expressed as 3200 BAR. It is the standard currently followed by Sellier & Bellot, Remington, Winchester, and PRVI, the companies that actually produce the ammunition sold under many brand names. I am aware of the 40 kpsi SAAMI PMAP standard, however, it isn’t applied to most production and it is only a reference pressure, not a mandated specification.

The military high spec for the cartridge, MIL-C-743A issued in 1949 and remained in place through 1997, was 47,500 +/- 2,500 psi. I believe the cartridge actually started at 32,000 psi then progressed to 40,000.

SAAMI is the “bible” 95% of the time, but there are times when other recognized standards group also apply.


Joe

 

[Ed Ames]

CIP doesn't use the same test methodology for measuring pressures. You can't compare the numbers directly because they are measured differently. The author just messed up (comparing apples to oranges) and is now trying to "baffle 'em..."

The rifle was designed for a 40kpsi max pressure. The proof load/blue pill pressure was 47.5kpsi, when using the same methodology SAAMI uses.

 

[Barry the Bear]

Real Guns is one guy and his wife. He's an arrogant hack that runs a gun shop and writes articles. When he gets his facts wrong, he will argue, deflect and ultimately drag the messengers name through the mud.

Kinda like a certain .30 carbine fan we know.

 

[eldon519]

Ed beat me to it. Measuring the same load with CIP and SAAMI methodologies will yield two different results.

 

[jski]

Alright guys, I must admit that I posted this with a certain degree of trepidation. This doesn't give poor ol' Joe a chance to defend his "honor" ... so to speak.

Also, I was unaware of CIP. SAAMI is the only standards I was aware of. Interesting, NATO uses yet another: EPVAT.

I have to admit guys, when I look at Hodgdon's reloading data website, the highest pressure loads don't necessarily equate to the best performing loads. So, I'm not sure this tells us much?

And Barry, that's below the belt ;-) but, I must admit, somewhat humorous.

 

[CraigC]

For a six page "argument", I think this has been very civil and we could all still meet up for lunch & shootin' without breaking out into a fist fight.

 

[jski]

CraigC, sounds good to me. Just let me know when and where;-)

 

[Jason_W]

Apologies if this has already been mentioned in this thread, but Henry will apparently be releasing a carbine in .327 next year.

http://www.personaldefenseworld.com/2016/12/henry-repeating-arms-rifles/

My interest in the round has been renewed.

 

[LOLBELL]

CraigC, sounds good to me. Just let me know when and where;-)

Not CraigC here, but how about Central Alabama- bout mid point between you guys

 

[jski]

I do believe CraigC was correct with his opinion on Real Guns. This is my last communication from "Joe":

The problem is that some folks find the SAAMI site, download or looks up reference sheets and have no other agency or industry information for context. Please do not write anymore. I am always happy to talk about firearms and provide information, but I don’t have the time to waste on Internet trolls.

If you guys remember, my sole communication with Joe was:

In your article you stated: "The 30 Carbine also packs more pressure than the other two rounds with 46.4k psi, compared to 44.9k psi for the 327 Fed Mag and 35.0k psi for the 357 Magnum."

The figures look correct for the .357 and .327 mags. but the SAAMI spec for the .30 Carbine is 40K psi. Is there another source you used?

Plus an offer to share some of your responses, if he were interested.

 

[CraigC]

What part of Alabama? My mother's family is from Eufaula and I have cousins in Birmingham.

That's the way he acted when I provided the CORRECT information about the new Ruger .454 and .480 Bisley's last year. Actually slandered me on Facebook.

 

[eldon519]

My mom's side is from around Gadsden. That little main street part of Eufaula is one of the prettiest streets anywhere, especially when everything is in bloom.

 

[khari]

Meetup at CMP Talladega?

 

[LOLBELL]

What part of Alabama? My mother's family is from Eufaula and I have cousins in Birmingham.

That's the way he acted when I provided the CORRECT information about the new Ruger .454 and .480 Bisley's last year. Actually slandered me on Facebook.

In the Fayette area, West of Tuscaloosa