So I just bought a 10" barrel chambered in .429 Desert Eagle.  It's a .50 AE case necked down for a .44 caliber bullet.  This had been done before in the '90s as the .440 Corbon.  This one apparently has a slightly different shoulder angle to address some issues with the older cartridge.  

Even though it's been out for a few years now, there still seems to be nothing out there for published data.  And this is the type of cartridge that will not get very far if people are relying on shooting factory ammo only.  

I did email Hodgdon already asking if they have developed any data, or if they have any plans to.  I'll report back if I hear anything from them.

The closest I've found so far is some info on The High Road where someone worked up some loads using H110.  Farther down in that thread is some data that was reportedly supplied by Magnum Research.  

I also found some Quickload info over at Calguns.  

Just checking to see if there is anything else out there.  .440 Corbon data would be a good starting point as well.  Or at least a good guideline.  

This looks to have some pretty good potential.  Over in the Arfcom Desert Eagle forum, we have reported velocities from factory ammo of 1790 fps. for a 240 gr. JSP, and 1943 fps. for a 210 gr. JHP.  I'm thinking we should be able to get up around 2100 fps. with a 180 gr. bullet.  You know, varmint loads for the Desert Eagle.  .

Just looking for any additional insight out there.

Sounds like a fun gun to shoot. Hope you get some help, I will follow along.

Reply from Hodgdon is that they currently do not have any data for the .429DE. No mention if they intend to develop data or not.

I was able to get out and run a few factory rounds through the gun. All went well. Otherwise, I’ve gotten as far as prepping brass, but otherwise have not done much with load development. Hopefully I’ll get some test loads put together and tested this week.

That sounds like a thumper.

Although I suppose from a parts & ammo perspective, going with one of your .458 SOCOM uppers would make more sense today. But an AR15 in .429 /.440 sounds like a lot of fun.

That also sounds excellent. Again, not as practical from a parts perspective, but I kind of like unique stuff like that.

I loaded and shot some 240 gr. Zero JSP over 28.5, 29.0, and 29.5 gr. of H110.  Average velocities were 1688, 1703, and 1754 respectively from the 10" barrel.  No excess pressure signs with fired primers still showing rounded edges.  

The Glacer Ridge factory ammo I shot pushed a 240 gr. bullet a little faster at 1814 fps.  I think I may try to bump this up just a little more.  

Still thinking about working up some loads using lighter bullets.  I suppose I should break down and get a copy of Quickload at some point for stuff like this.

So I went up to 30.0 gr. H110 with the 240 gr. Zero. Velocity was 1749 fps, which is just slightly slower than the 29.5 gr. load. Everything was loaded the same. It was 88°F when I tested the first loads, and only 70°F for the 30.0 gr. load.

Odd, I know H110 is somewhat temperature sensitive from summer to winter, but I wouldn’t think a less than 20° difference would be noticeable.

What I did notice is that the higher load shot more consistently and accuracy was better. I think I might standardize with this load.

Primers all looked the same as with the lighter loads.

I also found some AA#11FS and loaded 28.6, 29.0, and 29.5 gr. with the same 240 gr. bullet. Velocities from the 10” barrel were 1671, 1697, and 1712 fps respectively.

It seemed so shoot a little softer than the H110 loads, but that could have been my imagination. Accuracy with these was all very good as well.

Ok, looking through my stuff, I have a box of 180 gr. XTP and a box of 200 gr. Gold Dot bullets.  

The Gold Dots are marked as being intended for the .44 Special.  I'm thinking the .429 is going to push them just a bit faster than they were designed for.  They probably wouldn't penetrate very far, but I bet they make a mess of whatever they hit. That is if they don't come out of the barrel tumbling. Maybe I'll save them for later...

But I figure I can use the AA#11FS data for the 210 gr. bullets as a starting point for the XTPs.  I'm not usually all that excited about going out on a limb with no good data.  I'm thinking if i work up the 180 gr. XTPs to maybe 5-6% over the max load for the 210 gr. bullets should still keep me out of danger.  I have a handful of cartridgs loaded at 31.5 gr. and 32.0 gr. of AA#11FS.  

I'll see what they do and report back...

I had seen that, but so far haven’t tried reforming any .50 brass.

A couple thoughts:

1. When you reform, do you lube inside the case neck? I have found when reloading some bottleneck cases, the expander plug will grab and pull the neck as the case is being removed from the die. This changes the shoulder angle slightly. Although what usually happens here is the round will chamber, but will be sticky if you try to remove from the chamber without firing.

2. Modify the least expensive / easiest to replace component. If it’s only a difference of .018”, I would modify the shell holder rather than alter the die.

I’ll try reforming a couple .50 cases and see if they will chamber in my barrel.

@RiverSwine45
Good so far.  I took a Starline .50AE case, lubed it, and ran it through the. 429 sizing die.  It plunked into the chamber to what appears the same depth as a sized .429 case.  I then dropped the slide on it, and it closed completely.

I then trimmed to 1.275" to match the rest of my .429 brass. I primed and loaded the case, and it again chambered and the slide closed fully. The live round extracted and ejected normally.  I'll report if there are any abnormalities shooting it.

I am using an RCBS Rock Chucker press, with the sizing die set so the handle just starts to cam over on the full stroke.  I'm using Lee dies.

Ok, just got back from the range.  As noted, I have loaded some 180 gr. XTPs with AA#11FS at 31.5 gr. and 32.0 gr.  Velocities were 1889 fps and 1936 fps.  

Primers still look good with these loads, so I think I'll try to slowly go up a little more.  

Accuracy was also good with 25-yard groups of 1-1/2" and 1-3/4".  

I also stretched out and shot a couple of magazines of the 240 gr. Zero JSP with 30.0 gr. H110 at 100 yards from the bench.  Overall not unhappy, although I think I could likely do better with some more practice.  The first 6 shots made a group of 7-3/8".  Of the second six shots, only five appeared on the paper. I'm not sure where the 6th went.  I'm going to blame the loose nut behind the trigger.  

Sighted at 25 yards, I'm hitting about 6" low at this distance.  I think I may adjust the scope up a bit, and probably end up about an inch high at 25 yds.  I can live with that.



One other item of interest. I have now had 3 or 4 malfunctions where the case flips completely around and the mouth gets munched by the closing bolt, destroying the case.

You can see where I moved the scope forward somewhat, to try and avoid having the case hit the rear of the scope. I’m still getting hits there, and I’m afraid it will eventually start scratching the lens.

I wonder if it will help if I move the scope farther to the rear. The case will likely bounce off the bottom of the scope bell, but won’t hit the lens. This may also help ricochet the case away before the slide closes on it.

Maybe.

Here’s what the failure looks like.