44 mag case not expanding?

[coondogger]

I just ran some 44 mag rounds through my Rossi 92 lever gun. I used a 165 lead round nose projectile powered by 6.5 grains of Universal. It generates 10,350 psi. This is from the latest edition of the Lee Precision loading manual. Here's the problem. The cases are exceedingly blackened after firing. I'm wondering if there is insufficient case pressure to fully expand the case in the chamber. So there is a slipstream of gasses backwards from the mouth of the case along the outside of the the brass. While this is possible in theory, I find it hard to believe they would publish a recipe with this built-in fault. Any thoughts?

 

[Soonerpesek]

That is very possible if that is a listed STARTING load.
Might need to up the powder charge for improved obturation…

 

[243winxb]

SAAMI Maximum CUP 40,000. Hodgon has 11,500 CUP @ 7.2 grs at maximum. 1138 fps. A low pressure loading.

 

[coondogger]

I believe I will. But for the current batch I’m putting a heavier crimp on the bullet. Just to eliminate that as a possibility. Then I load some with 6.8 g. (7.2 is max).

 

[GeoDudeFlorida]

I used a 165 lead round nose projectile powered by 6.5 grains of Universal. It generates 10,350 psi. This is from the latest edition of the Lee Precision loading manual.

A couple of questions which may help you with this:
1 - you say “a 165 lead round nose,” but is it the same lead round nose? Is it the same length and diameter as the one tested? If they are only similar then how similar? You’re assuming a very precise pressure but is it accurate?

2 - while scorching might be annoying it does not necessarily - or even typically - indicate a dangerous condition. It probably does indicate a delay between the point where sufficient pressure has built up to dislodge the bullet and the point where the case mouth has expanded sufficiently to seal completely. How far down the case does the scorching stop? Are you seeing signs of hot gases on the breech face? Is the velocity consistent (low standard deviation) and is it in the predicted range according to the loading tables?

 

[GRIZ22]

Low pressure load. End of story

 

[Bronco72]

Maybe a heavier bullet is required ?

 

[Walkalong]

Yes, the lighter bullet and a low charge weight combined is the issue.

 

[AJC1]

The solution your looking for is a faster powder to get a higher peak pressure, at the same velosity. If your not needing that low velosity up your charge till it goes away. You will need to scrub your chamber...

 

[MEHavey]

Insufficient to expand/seal the case mouth

 

[MEHavey]

10,350 psi

Insufficient to expand/seal the case mouth

Also: I've looked at the Lee Manual (p 562).
That "165gr Lead Bullet" section is pure powder puff.
The Starting 6.5gr/1.5" Universal Load doesn't even break 8,000 psi
Fine to shoot for fun, but it's going to "soot up" the cases no matter what.

Unless the lead bullets you're using advertise themselves as pure lead, I'm going to predict they are likely Lyman#2 hardness (BHN 15)
Even bare-based/no gas check they can handle 18-20,000 psi.
I suggest at least 8gr Universal to get to into the 13-14,000 psi range

Your mileage may vary of course (so take care ), but that is a 40,000 psi-rated cartridge/gun

 

[Bazoo]

Low pressure loads do that. You might get the load to seal if you use Remington brass.

I have a batch of Hornady brass that soots the case all the way back to the primer with medium pressure 44 Special loads, but didn't with a magnum load.

 

[Riomouse911]

I get that a lot with light bullet loads in .44 Spl-.44 Mag-.45 Colt.

The 165 gr TCFP from MBC over a mild charge of AA#5 soot up like a chimney in .44 Spl cases.

Stay safe.

 

[coondogger]

Insufficient to expand/seal the case mouth

Also: I've looked at the Lee Manual (p 562).
That "165gr Lead Bullet" section is pure powder puff.
The Starting 6.5gr/1.5" Universal Load doesn't even break 8,000 psi
Fine to shoot for fun, but it's going to "soot up" the cases no matter what.

Unless the lead bullets you're using advertise themselves as pure lead, I'm going to predict they are likely Lyman#2 hardness (BHN 15)
Even bare-based/no gas check they can handle 18-20,000 psi.
I suggest at least 8gr Universal to get to into the 13-14,000 psi range

Your mileage may vary of course (so take care ), but that is a 40,000 psi-rated cartridge/gun

I ran a second batch using Trail Boss. It produced a much higher pressure -- around 18,000. Still sooted up.

 

[goon]

I’ve noticed a fair amount of scorching like this with milder .38 Special loads. Agree that it’s just a low pressure load, and it’ll probably go away as you work the charge up.

 

[Walkalong]

.44 Mag cases are pretty tough, designed to take high pressure

 

[reddog81]

I find it hard to believe they would publish a recipe with this built-in fault. Any thoughts?

There is no built-in fault there, that's just what happens with really light loads. Different guns with different chamber sizes or using bullets made of different materials sized to different diameters might yield different results. You're using a light charge on a light bullet that is probably sized .429 and shooting down a barrel that probably has a .432 groove diameter.

 

[MEHavey]

As note abovez:
- 'Recipe's' doin' what it oughta.
- 44 MAG brass is doin' what it oughta.

Don't worry about (or expect not to get) soot w/ that low-powered combination