450 Mongo

[dannyabear]

Does anyone have any info or load data for this cartridge?

 

[Steve Koski]

Is that the short version of the .45 GAP?

 

[TN Shooter]

Danny:

I once messed around with this round for several months when I owned a Rexio .45 LC/.410 single shot handgun. I was getting gawd-awful accuracy with regular .45 LC ammo and I thought that getting the bullet closer to the rifling would help. It did, but not a whole lot. As it turns out, the workmanship of the pistol was very poor, so that was probably the cause of the problem. Nevertheless, the idea of having a do-it-all handgun was the driving force behind the experimentation. I was getting great results from the various shot loads I was trying but I couldn't get acceptable accuracy using solid ball projectiles.

To make .450 Mongo brass, I used both .303 British brass and .444 Marlin brass that I would fireform in the Rexio's chamber to hold a .45 LC bullet. I did this by using a healthy powder charge of a fast-burning powder like Bullseye, wadding, corn meal filling, and then a wad of wax to hold it all in place. The .444 Marlin seemed to work better because the .303 brass was so much thicker in the base area and it didn't expand as well. I used a Lee Universal Decapping die to decap and then a .45 LC resizing die to resize the area of the brass holding the bullet. I seated the bullet and crimped with a regular .45 LC die

Due to the unknown strength of the Rexio handgun, I kept the loads in the medium-to-warm range for a .45 LC (bearing in mind that there was a lot more case capacity in the .450 Mongo brass). Besides, I was going for greater accuracy instead of a hand-cannon load (definitely a wise choice given the poor workmanship of my particular pistol). I noticed that I got less vertical stringing when I used a polyester filler to keep the powder in the back of the case next to the primer.

For accuracy, my best results were with hollow-base 250 grain .454 bullets (unsized and lubed with Lee Alox) that I cast myself. The next best results were with .454 round lead balls. For whatever reason, this pistol seemed to like none of the conventional .45 LC bullets.

Recently, I got a 5-shot Taurus .45 LC/.410 revolver. This gun shoots regular factory .45 LC ammo SO FREAKIN WELL that I haven't bothered with the .450 Mongo loads. However, it doesn't pattern the shot loads as well as the Rexio because it lacks the "choke" that stops the spinning of the .410 wad. With these handguns, the best patterns are with the shorter barrels.

I would be interested to hear about any experimentation you do. Remember to BE SAFE and HAVE FUN!

 

[dannyabear]

Thanks for the info; I have the same pistol except now it is called a Super Comanche. And i'm looking for the same thing, just better accurcy not more power. I think the 444/45 load should be called a 45 XLC.
I'm picking up some 444 brass tomorrow and will work on it next week;
It is a cheap gun but it is a Hoot to Shoot/thanks again

 

[wmbwinn]

more ideas here:

http://www.thehighroad.org/showthread.php?t=6686&highlight=450+mongo