Update on developing new load for .30 Carbine Blackhawk

[jski]

Just got back from shooting my "experimental" loads:

1. 7.7 gr of Ramshot True Blue
2. 115 gr GC, Linotype RN bullets
3. CCI Small Rifle Magnum primers

The case capacity of the .30 Carbine is 21.050 gr H2O and 19.0 gr H2O for the .327 Magnum. Meaning the .30 Carbine has an 11% greater case capacity. The max load for a 115 gr bullet in the .327 is 7 gr of True Blue, so 7.7 gr for the .30 Carbine seemed reasonable.

The result from shooting 100 7.7 gr rounds: they were very pleasant cream puffs, much softer than my rounds loaded with 15 gr. of Hodgdon's H110. As a matter of fact, my wife tried them out in her M1 Carbine and they consistently failed to cycle. With the M1 Carbine, the spent cases barely came out. Instead of the cases flying high overhead and far away, these cases flew low, landing next to the gun. And that's only when they came out.

As for the Blackhawk, at 35 yds, they were as accurate as my rounds with 15 gr of H110.The recoil from the Blackhawk was very mild but a few of the cases required more than a gentle tap from the ejector rod to get them to come out. I'm only talking about a very few, maybe a half dozen out of a 100 rounds.

But these were new cases from Hornady. I've never used Hornady's brass before so I have no experience with which to judge this. All my previous experience has been with Starline brass and I must say I believe that Starline offers a superior product, at least in the case of .30 Carbine brass.

As for the primers, I saw to obvious signs of over pressure. They appeared no different from the spent primers from my H110 loads.

 

[jski]

BTW, someone asked if there were any indications of high pressure?

Absolutely not, quite the contrary, the fact that these rounds consistently failed to cycle my wife's M1 Carbine tells me there was insufficient pressure generated for that purpose. My rounds with 15 gr of Hodgdon's H110 never failed to cycle the M1 Carbine. I'd also add, the recoil from the Truth Blue rounds was much gentler than the H110 rounds, as I said they were real cream puffs.

 

[Walkalong]

A round can have high pressure and not cycle an auto, depending on the powder speed, but it does indeed sound like you are fine. Are you going to bump it up a hair to get 100% positive cycling and see how they are?

 

[Toprudder]

The velocity of the bullet is a result of the total "area under the curve" pressure, not the peak pressure. The peak pressure is the limiting factor for how hot you can load any given powder. The peak occurs very soon after ignition. With fast powders, this could occur before the bullet has fully left the casing; also, the pressure drops off much quicker with fast powders compared to slower burning powders. In the case of the M1 Carbine, the gas port for operating the bolt is about a third of the way down the barrel, so the pressure available at the gas port is the important factor for reliably cycling the action, not the peak pressure that occurred much earlier. A fast burning powder will have much less pressure at the gas port, slower burning powders will have more pressure.

Also, magnum primers have thicker cups and can withstand higher pressures than standard primers. They would not be a reliable indicator of pressure, IMHO.

 

[WelshShooter]

That's interesting, I use True Blue for gallery loads in my Marlin 1894 using a 158gr 357mag load. I use Accurate No2 for my M1 carbine gallery loads, but my carbine is a straight pull rifle as I'm in the UK. I don't need the rifle to cycle is it's all manual extraction, so this would be interesting to try out with cast bullets.

 

[jski]

Actually, that is the purpose behind this experiment: trying to use a faster (than Hodgdon's H110) burning powder for my .30 Carbine loads for my Blackhawk. As most are aware of, any .30 Carbine ammo you might buy at your local gunshop is intended for the M1 Carbine rifle with its 18" barrel, NOT the 7 1/2" barrel for the Blackhawk.

Ramshot's True Blue seemed like an excellent candidate because it has a 2X faster burn rate than H110 and meters well with small loads (< 10 gr). Unfortunately but not surprisingly, most of the pistol powders I considered didn't have data for the .30 Carbine, so I'm left winging it a bit.

What is my next load? I'm think of going to 8.7 gr. of True Blue.

 

[WelshShooter]

If you have it, try Accurate No 2 or Alliant Bullseye. Here's some pics from my load development along with some chronograph information (from Magnetospeed). These were from 115gr cast bullets all seated at 1.670" overall length. This was shot from a bench at 25m at local indoor range. Sight was set to 250 yards and point of aim was 6 o'clock. I didn't care for shot placement, just group size. My gallery range has limits on muzzle energy, and for a 115gr projectile I must ensure my velocity is below 1,350fps. My testing concluded that my loads were within the range limits and were safe to shoot. I've shot around 500 of these gallery loads with no problems. Cases are soot free (much cleaner than H110!) which shows that the case obturates and is not too low pressure.

I think these loads should work well in your revolver!

I used QuickLoad to determine the starting and finishing loads. 5.50gr of Bullseye would generate 29,765psi which is well below max of 38,500psi so I know my testing up to 4.5gr was safe.

5.50gr of D032 would generate 33,459psi which is well below max of 38,500psi so I know my testing up to 4.7gr was safe.

Bullseye Load. Best group was 3.3gr. 5 shots per load.




Lovex D032 (it is exact same powder as Accurate No 2). Ten round groups. Good grouping at 4.4gr and 4.5gr. Shot placement was pretty spot on, despite using same POA as the Bullseye loads.

 

[Walkalong]

What is my next load? I'm think of going to 8.7 gr. of True Blue.

That's a big jump.

 

[Toprudder]

What is my next load? I'm think of going to 8.7 gr. of True Blue.

That is more than a 10% jump all at once. I normally work up loads in 0.2 or 0.3gn increments. I always try to approach max loads cautiously, and that is when I am working with published load data.

 

[jski]

If you have it, try Accurate No 2 or Alliant Bullseye. Here's some pics from my load development along with some chronograph information (from Magnetospeed). These were from 115gr cast bullets all seated at 1.670" overall length. This was shot from a bench at 25m at local indoor range. Sight was set to 250 yards and point of aim was 6 o'clock. I didn't care for shot placement, just group size. My gallery range has limits on muzzle energy, and for a 115gr projectile I must ensure my velocity is below 1,350fps. My testing concluded that my loads were within the range limits and were safe to shoot. I've shot around 500 of these gallery loads with no problems. Cases are soot free (much cleaner than H110!) which shows that the case obturates and is not too low pressure.

I think these loads should work well in your revolver!

Were these fired from an M1 Carbine or a Blackhawk? I assume the answer is M1 Carbine.

BTW, thanks for both the time and effort putting together that presentation.

 

[jski]

That is more than a 10% jump all at once. I normally work up loads in 0.2 or 0.3gn increments. I always try to approach max loads cautiously, and that is when I am working with published load data.

I think I'll drop down to 8.5 gr of True Blue. It's just seems I should both proceed cautiously but also get something that would be noticeable a step up.

BTW, I need a new chronograph. Any suggestions?

 

[Toprudder]

BTW, I need a new chronograph. Any suggestions?

Three types of chronographs: Optical (most popular, many brands), magnetic (Magnetospeed) and radar (LabRadar).

If money is no object, get the Labradar. $550+. Does not have to be in front of the firing line, so no chance of it getting shot. Can tell the velocity of the bullet well downrange (up to 75 yards for a 223 bullet).

Magnetospeed mounts to the barrel, so may not work with some guns (snub nosed revolvers, for instance).

Optical - many brands available. I have a Caldwell that works with my iPhone, and really like it. Before that, I used a F1 Shooting Chrony, that I still have as a backup. Not as nice a user interface as the Caldwell, but it will operate standalone and give statistics, whereas the Caldwell chrono in standalone will only show the last shot velocity, the app on the phone must be used for statistics (which the app is very nice!). Competition Electronics makes the Pro-Chrono which is a nice unit as well. The optical chronos are about $100, sometimes $80 on sale.

The downside to the optical chronos is that they must be place in front of the firing line, and the bullet must pass just over the top of the sensors. This makes them very susceptible to being hit by the bullet. I am proud to say that I have shot well over 1000 shot groups across my Caldwell and have not hit it (yet). The opticals are also susceptible to lighting conditions, I sometimes have to tilt mine so the sun is not shining down into the sensors.

 

[Toprudder]

IMHO, jumping from 7.7 to 8.5 in one step is not proceeding cautiously. I would try 8.0 first, just load a few rounds.

I typically will carry loads to the range to test, with 5 or 6 steps in charge, maybe 5 rounds each. I've been known to stop before I get to the highest charge, and pull the ones I did not shoot. But, that is MY way of being cautious.

 

[WelshShooter]

Were these fired from an M1 Carbine or a Blackhawk? I assume the answer is M1 Carbine.

BTW, thanks for both the time and effort putting together that presentation.

These were indeed from an M1 carbine. The point I was trying to make was that those powder charges had enough pressure to shoot the bullets out of the rifle without getting stuck in the barrel. Therefore, these should work with your shorter barrel revolver

 

[jski]

IMHO, jumping from 7.7 to 8.5 in one step is not proceeding cautiously. I would try 8.0 first, just load a few rounds.

I typically will carry loads to the range to test, with 5 or 6 steps in charge, maybe 5 rounds each. I've been known to stop before I get to the highest charge, and pull the ones I did not shoot. But, that is MY way of being cautious.

Thanks for your input. I haven't loaded anything yet so nothing is cast in concrete. I think I'll take up your cascading suggestion.

 

[jski]

Three types of chronographs: Optical (most popular, many brands), magnetic (Magnetospeed) and radar (LabRadar).

If money is no object, get the Labradar. $550+. Does not have to be in front of the firing line, so no chance of it getting shot. Can tell the velocity of the bullet well downrange (up to 75 yards for a 223 bullet).

Magnetospeed mounts to the barrel, so may not work with some guns (snub nosed revolvers, for instance).

Optical - many brands available. I have a Caldwell that works with my iPhone, and really like it. Before that, I used a F1 Shooting Chrony, that I still have as a backup. Not as nice a user interface as the Caldwell, but it will operate standalone and give statistics, whereas the Caldwell chrono in standalone will only show the last shot velocity, the app on the phone must be used for statistics (which the app is very nice!). Competition Electronics makes the Pro-Chrono which is a nice unit as well. The optical chronos are about $100, sometimes $80 on sale.

The downside to the optical chronos is that they must be place in front of the firing line, and the bullet must pass just over the top of the sensors. This makes them very susceptible to being hit by the bullet. I am proud to say that I have shot well over 1000 shot groups across my Caldwell and have not hit it (yet). The opticals are also susceptible to lighting conditions, I sometimes have to tilt mine so the sun is not shining down into the sensors.

Had Magnetospeed suggested to me but I'm not convinced this is a good solution for pistols, e.g., my Blackhawk with a 7 1/2" barrel.

 

[Toprudder]

If I only shot rifle, I might go with Magnetospeed. I'm saving up my coin for a Labradar. I have a friend that has one, and occasionally I get to use it. I could use that at the indoor range to check my pistol loads (not allowed to put anything in front of the firing line, so no optical chronos).

 

[jski]

Quick update: I took my hogleg (Blackhawk) out to the range and shot my 8.5 gr True Blue rounds with 115 gr Linotype bullets. At 35 yards it was dead on. No sign of over pressure yet.

Still haven't purchased a new chronograph yet. Still trying decide which would work best with my pistols?