Duplex Bullets in a 357

[Ganderite]

This my current project. 115 gr SWC on a 95g CamPro. Total 205 gr.

357 case with 2400. Cases were already primed with a S&B standard primer. 2400 really needs the magnum primer, otherwise ignition is poor and the ES is high.

I loaded 5 rounds with 9.5, so I could shoot 3 at a paper target (5, 10 and 15 yards) and then 2 at the chrony.

On paper, at 5 yards the two bullets were 1/4" apart.

at 10 yards they were 1/2" apart.

At 15 yards, 1 inch apart. (You can't see the bullet kissing the edge of the paper in the picture.)

I also loaded 2 each of 10.0, 10.5 and 11.0 for the chrony. I was looking for 1200 fps. Did not quite get there. 11.2 would be about right.

For a 38SPl, 7.0 gr of 2400 is about max at 850 fps.

 

[MuthaFunk]

Madness!!!! The things you get up to! lol

 

[Janeau]

Has long that you do not blow yourself or the gun..why not ! Another idea will be to use a plated wadcutter 148 grains cut in 2...

 

[Ganderite]

Tried 11.2. Velocity was still well under 1200 fps, but the ES improved. 11.5 looks like the load.

On paper, the separations were the same at 10 yards (1/2") and at 15 yards (1")

 

[Ganderite]

Has long that you do not blow yourself or the gun..why not ! Another idea will be to use a plated wadcutter 148 grains cut in 2...

You cut them, I will shoot them. I tied that about 4 years ago. No easy way to cut a bullet in half, if you want to make more than a handful. best is to use light bullets or round balls.

 

[Snider shooter]

I had a similar idea but I used buck shot instead. I drilled a hole in a piece of steal plate and beat the 00 buck flat. Three in 38 and four in357. I coated them in Lee lube sized them 359. I weighed them and used the data from a bullet weighing the same. Would make a deadly close quarter round.

 

[Ganderite]

I had a similar idea but I used buck shot instead. I drilled a hole in a piece of steal plate and beat the 00 buck flat. Three in 38 and four in357. I coated them in Lee lube sized them 359. I weighed them and used the data from a bullet weighing the same. Would make a deadly close quarter round.

Did they lead the barrel?

 

[Snider shooter]

I decided to check for leading after firing 24 rounds. I ran the brush down with some Hoppes a half dozen times. The thought crossed my mind that if I ever needed to use such a load I probably wouldn’t need to fire 24 rounds. Some of the pieces stayed together making one hole.
A short range defence load you probably wouldn’t need a full cylinder load of 18 bullets hopefully.
Another multi projectile load I tried was with my 14ga percussion shotgun. I picked up a few spent 22 casings and loaded them. Does a good job on pumpkins.

 

[Ganderite]

OK. Testing is complete. I used 2400 over a S&B standard primer, because the brass was already primed when I decided to do this. When I load from scratch I will switch to the CCI Magnum primer, because 2400 can be erratic when downloaded.

Bullet weight 205gr (115 + 95)

9.5 - 932 fps
10.0 - 1020
10.5 - 1035
11.0 - 1124
11.5 - 1141
12.0 - 1167

3 shot average form a 4" barrel.

I will use 12.0 gr as my standard load. Cases extract smoothly.

the 12.0 gr load put the 2 bullets 1" apart at 15 yards.