M3 Grenade Launching cartridges........

[BossHoss]

Seeing how scarce these are, I was wondering if anyone had a source for them.

Also, after a lot of reading it seems that they may be easily made by an accomplished reloader.

Anyone here ever make their own ?

I got my hands on a M7 for my Garand, and have been collecting Practice Grenades for a while, and would like to try to lose a few!!!

[AllanD]

Somewhere I have two of the sealed "spam tins" of grenade launching blanks.

If I stumble across them I'll take and post a picture

AD

[Outpost75]

Original USGI WW2-era grenade launching blanks were a duplex IMR1175 and A5 black powder load.

You can get almost identical results mixing 1 shot glass of 3Fg Goex with three shot glasses of IMR4895, IMR4064, RL15 or Varget, mixing thoroughly, then filling a .30-'06, 7.62mm NATO, 7.62x39, or 5.56mm case full to the shoulder, pushing a Dacron polyester fiber filler into the case neck, then plugging the neck with Gulf canning wax and crimping the mouth closed with needle-nosed pliers. We used these to launch a 1 kilogram steel proof slug off the rifle with the buttstock rested on concrete to test synthetic stocks for cold-weather breakage. At -50 degs. F a birch Ruger Mini-14 GB stock was reduced to splinters, but a laminated one of Maine yellow birch passed with flying colors.

[BossHoss]

Somewhere I have two of the sealed "spam tins" of grenade launching blanks.

If I stumble across them I'll take and post a picture

AD


Thanks,....I will be drooling....If you wish to part with one ...let me be first in line.


Outpost, thanks for the reply. I am interested in someone's results launching Practice Grenade from a M1 Garand with a M7 and a modern load. One of the FA heads recommended removing the BP from the duplex load, his tests showed it wasn't needed, the myth was it helped ignition.. After the war it WAS removed from subsequent loadings.

All of this written knowledge is great, I would just like a post from someone who has done it (made their own M3 equiv) AND has launched M31 Practice Rifle grenades with them.

[Outpost75]

Thanks,....Outpost, thanks for the reply. I am interested in someone's results launching Practice Grenade from a M1 Garand with a M7 and a modern load. One of the FA heads recommended removing the BP from the duplex load, his tests showed it wasn't needed, the myth was it helped ignition.. After the war it WAS removed from subsequent loadings...

Good info. When I was at Ruger in the 1980s the company made modified GB models for the French Gendarmarie and they had a requirement to be able to launch grenades and also to be able to throw a 1 kg proof solid steel slug at a minimum velocity and range which was used by entry teams for door breeching. VERY effective!! Found out later that the French police actually were launching the door breeching slugs with M193 Ball as they said the slug was designed as a bullet trap and would heave the 1 kg cylindrical steel projectile at 200 +/- 10 m/s!

We loaded our own 5.56mm grenade launching blanks using the 4895-3Fg mix and they worked fine.

Of course you wouldn't want the BP fouling in an M16 gas tube, but the duplex loading caused no issues for the Mini-14GB and AC556 and was addressed by ordinary cleaning measures.

[AllanD]

Thanks,....I will be drooling....If you wish to part with one ...let me be first in line.


Outpost, thanks for the reply. I am interested in someone's results launching Practice Grenade from a M1 Garand with a M7 and a modern load. One of the FA heads recommended removing the BP from the duplex load, his tests showed it wasn't needed, the myth was it helped ignition.. After the war it WAS removed from subsequent loadings.

All of this written knowledge is great, I would just like a post from someone who has done it (made their own M3 equiv) AND has launched M31 Practice Rifle grenades with them.

I also have two white-star parachute flares made to be fired from a rifle grenade launcher.

Like most reloaders and/or "gun enthusiasts" I am a pack-rat, and I don't "visit" surplus stores as much as I search every "nook" & "crannie", very little escapes my searching eyes!

[BossHoss]

Those are awesome, I would love to light up my river valley with one on a moonless night.

I have been searching nooks and crannies for militaria, at every mom and pop shop, and every once in while find something to make it worthwhile.

I found a Camillus MarkII Fighting Knife(Early KA BAR before the name was used) marked U.S.M.C. just a week ago, got it so cheap I was stunned. Found a box of M31's a while back, they were shot and dented, but still good for a little more practice. Just found the M7 adapter last Sunday.

I am going to make the cartridges , I just would like to know from someone who made them, if they used 4895, was it a full case , wadded, sealed and crimped. I know re-enactors use the parade blanks to throw them a 100ft or so, but I want to send them the real distance using the sight and graduations and table. Just for fun, and nostalgia.

There is a good amount of info out there on the M3, just no testimonials on a modern loading. I wouldn't experimenting a bit, If I had a beater rifle and some extra parts. And it may come to that. Just gonna need another crate of M31's....