44mag Over Pressure?

[Pbaker]

Hi all,

I've been scratching my head over my latest 44mag loads I made. I'm experiencing bulging at the base, our web, of the case. I don't think I am making hot loads, but the brass says otherwise. Here's the details on the load;

1. New Starline Brass
2. 255gr RNFP (noe htc mold to be exact)
3. 19gr AA#9
4. WLP primer
4. OAL 1.615

I originally was shooting these out of my Henry and assumed it was case forming to the chamber. But I fired some from my SRH, and while not as bad as my Henry, it's still there. Not sure if it's a bad batch of brass, too hot, or ****ty powder, or ****ty chambers.

[onelight]

Have you done before and after measurements on them to see how much they are expanding in the web of the case ?
If you have a factory load before and after measurements it could give you a base line for comparison in your guns.

[Silver Jack Hammer]

Are you re-sizing with Dillon shell holders and RCBS dies? I have found the Dillon shell plate is thicker and prevents the brass from being run all the way into the RCBS sizer dies, at least with .45 Colt.

[Win94ae]

I get the same thing with my Marlin 1894, it happens with light loads too. It isn't quite as bad as yours looks. The chamber isn't quite right in mine; because with my super Blackhawk, that couldn't handle the full power loads, bulging was never an issue.

[trapper9260]

I have not seen any problems in my Marlin 1894 or my Redhawk. The brass is ok. Maybe someone else have any idea on it for what the OP asking

[winelover]

Are you sure it's not your dies oversizing the brass? Carbide dies have a reputation for that look.

Winelover

[Tatume]

What you are seeing is commonplace. It is not a sign of too much pressure. The case walls expand to the chamber walls. The solid case head does not. The difference is the bulge you see.

This is the result of normal manufacturing tolerances. There is nothing wrong with the chambers either.

[44MAG#1]

What your showing is normal. While I don't have the knowledge as some on here have I have been reloading for around 49 years or there about. 44 Mag much as any caliber.
If I would have a question about things such as this I would fire a few factory loads as a "control load" just to see. The FL may not use the exact same brass but it would give me an idea of where my loads fell.
Buffalo Bore has a "standard" load for the 44 Magnum that uses the 255 "Keith" bullet and they use Starline brass. While too long to feed from the magazine one could single shot load the rifle to use the BB ammo as a control load. While not cheap the BB ammo could answer your question as a control load.
I started loading when there weren't any computers and the availability of info as there are today and one had to do a lot of determining on there own. Today info is more plentiful which is good.

[Pbaker]

Thanks for the feedback everyone. None of these cases have been resized in the photos. However, I did resize a handful and took some measurements.

Before resizing, case diameter avg was .459, down towards the web measured .455-.456. bulge is noticable like shown in the pictures.

After sizing, case diameter avg was .451, with the web area averaging .455-.456 still. Bulge is also still noticable.

I am using Dillon carbide dies on a 650. All the brass is new, never fired (until now). It is weird how the web didn't expand as much as the rest of the case, yet after resizing, the web diameter is bigger. This tells me it did expand, and supports my theory of chamber forming (kind of). That's why I thought I might have an out of spec chamber, or maybe the guy who did the ramp feed/chamfer on the chamber was having a good time?

[megasupermagnum]

A quick check of the SAMMI website shows the chamber spec for a 44 magnum diameter is .4598" +.004". Your chamber is good to go. The cartridge spec for diameter is .4569" - .006". So the web is good, chamber is normal. Pistol sizing dies are always smaller than needed, but .451" is typical. Your load appears to be more than safe, and I see no pressure signs.

I don't know why, but it seems Starline brass shows the ring more than other brands. I wouldn't worry about it.

[Pbaker]

Thanks for the feedback mega. This is my first go with magnum rounds. I've seen signs of head separation in my rifle rounds before, so I was a little nervous about the rest of my loads (approx 250). I also cut a few cases in half to check for cracking on the inside, and all looks good to me. I just wanted to make sure I wasn't about to blow up my firearms, or get a bunch of stuck cases. Speaking of stuck cases, none of the rounds were hard to extract. They all ejected great from my Henry, and my SRH they pretty much fell out.

Again, thanks for the feedback. It's much appreciated!