Model 642 in .380 ACP. Wait, wut?

[Michael Tinker Pearce]

I have a Model 642 I've customized. In the course of this i lost a couple of parts and discovered i could pick up a 'stripped gun' kit off Gunbroker cheaper than i could buy the parts. This mean I had an extra cylinder assembly. I was talking to a buddy and had a weird idea- what If I cut the cylinder for moon clips and shot .380 ACP? Well that extra cylinder was just sitting there and I have a workshop, poor impulse control and a distinct lack of adult supervision so it was quickly done. I took it to the range and tested it and it works great. Ballistics are comparable to a 3" barrel .380 semi auto and recoil was practically no-existent. Y'know, for someone seriously recoil sensitive this might actually make sense. The Altamont grips are temporary; I'll be making my own.

 

[cfullgraf]

Interesting project.

The extra 380 ACP moon clip ammunition would be a bit easier to carry due to the shorter length than 38 Special.

 

[Tallball]

Great idea!

 

[NIGHTLORD40K]

Will it accept 9mm too?

 

[Pat Riot]

That’s a neat concept!

 

[Jim Watson]

What clip do you use?

 

[Mr. Mosin]

I love it

 

[fxvr5]

. . . recoil was practically no-existent.

Not really. Doing the math shows the (380) 95 gr. bullet at 900 fps produces about as much recoil as a 38 Special 148 gr. Wadcutter at 640 fps (ballistics from my S&W shorty). Recoil could be reduced to well below the 380 by shooting 38 Short Colt, and there's no need to modify the gun.

calculations for a 1 pound gun

148 grain wadcutter, 640 fps = 4.02 ft lbs recoil (38 Special)
95 grain bullet, 900 fps = 3.88 ft lbs recoil (380 Auto)
125 grain lead, 600 fps = 2.67 ft lbs recoil (38 Short Colt)

 

[fxvr5]

Will it accept 9mm too?

Chambers usually have to be cut to accept 9mm.

Smith & Wesson 9mm Revolver Rechambering

Send your Smith & Wesson Model 686, 627, 66, or 60 revolver to TK Custom. Your S&W will accept 9mm rounds after installing the 9mm revolver cylinder.

tkcustom.com

 

[Mr. Mosin]

Not really. Doing the math shows the (380) 95 gr. bullet at 900 fps produces about as much recoil as a 38 Special 148 gr. Wadcutter at 640 fps (ballistics from my S&W shorty). Recoil could be reduced to well below the 380 by shooting 38 Short Colt, and there's no need to modify the gun.

calculations for a 1 pound gun

148 grain wadcutter, 640 fps = 4.02 ft lbs recoil (38 Special)
95 grain bullet, 900 fps = 3.88 ft lbs recoil (380 Auto)
125 grain lead, 600 fps = 2.67 ft lbs recoil (38 Short Colt)

You quite finished ?

You forget to take into account the grips on the gun, and the fact that MTP has bear paws for hands (no insult intended Mr. Pearce). His definition of felt recoil and your definition are quite likely entirely different.

No need to nitpick trivialities

 

[Michael Tinker Pearce]

Will it accept 9mm too?

No, 9mm is not a straight-walled cartridge and the base is too big.

 

[Michael Tinker Pearce]

What clip do you use?

These are S&W 9mm clips. They needed slight modifications to hold the smaller .380 ACP rims.

 

[Michael Tinker Pearce]

Not really. Doing the math shows the (380) 95 gr. bullet at 900 fps produces about as much recoil as a 38 Special 148 gr. Wadcutter at 640 fps (ballistics from my S&W shorty). Recoil could be reduced to well below the 380 by shooting 38 Short Colt, and there's no need to modify the gun.

calculations for a 1 pound gun

148 grain wadcutter, 640 fps = 4.02 ft lbs recoil (38 Special)
95 grain bullet, 900 fps = 3.88 ft lbs recoil (380 Auto)
125 grain lead, 600 fps = 2.67 ft lbs recoil (38 Short Colt)

The math doesn't lie, does it? I think the range loads I was using are a lot milder than the 95 gr. load you specify.

 

[fxvr5]

The math doesn't lie, does it? I think the range loads I was using are a lot milder than the 95 gr. load you specify.

What ammo did you use? Did you chronograph it?

 

[Jim Watson]

If you feel froggy, SOME .38 Special cylinders will take SOME .38 Super ammo. It is an overload, though.

 

[BlackHand1917]

A couple of years ago Taurus made a .380 revolver. I don't know if it was any good.

 

[fxvr5]

A couple of years ago Taurus made a .380 revolver. I don't know if it was any good.

It's still on their website.

And:

https://www.shootingtimes.com/editorial/taurus-380-revolver-review/365617

 

[WestKentucky]

I had a Taurus .40sw revolver for a while. It was a truly great gun that I regret letting go of. The recoil comparison between a revolver and a semiauto is about the same as comparing apples and watermelons. Both make ya grin when you touch one off but that’s about where it ends. Revolver recoil is fast. You have the shot, the blast plate takes a haymaker and the gun moves. With a semiauto you have the shot, the barrel and slide move together to unlock the gun and the whole mass moves backwards slowly with spring tension pushing forward the whole time. When that travel is abrubptly interrupted you get a 1 pound slide hammer whack transferred to your wrist. It may be a few thousandths of a second but it is comparably slow, and when you feel it longer you perceive it as heavier. I’m not a huge fan of most polystriker whizbang .40sw but that revolver I had was sweet.

Take that cheap (yeah I know) box of .380 FMJ and run 5 through a semiauto and then 5 through the little wheelgun. Do it until the box is empty, and then somebody might have a valuable opinion, and my money says that the revolver recoil would be seen as easier on the shooter.

Edit to add, tinker keep it up. Another fine firearm modification that is somewhat off the wall but all kinds of fun and interesting.

 

[Michael Tinker Pearce]

What ammo did you use? Did you chronograph it?

Blazer Brass, and not yet, but it I looked at the box and it is a 95gr. Bullet. I'm going to borrow a 3" .380 and chronograph them side-by-side.

 

[toivo]

Sounds like a great idea. I have shot .32 ACP in my Ruger SP101 chambered for .327 Federal Magnum. It's a semi-rimmed cartridge, so no clips are necessary.

 

[fxvr5]

Blazer Brass, and not yet, but it I looked at the box and it is a 95gr. Bullet. I'm going to borrow a 3" .380 and chronograph them side-by-side.

It should be close to what I quoted. Blazer lists 945 fps and the 900 fps i used is based on 380 ammo that lists at 955 fps that was chronographed from a Taurus 380 revolver with a 1.75" barrel.

 

[doubleh]

Once again I am always interested in what you come up with in firearms. This one is not quite as wild and off the wall as most but I like it.

 

[ThomasT]

Gotta love it when MTP starts a thread. You know its going to be something crazy different.

@fxvr5 I have an S&W 431PD in 32 mag. I usually use 85gr JHP bullets loaded to the max with Lil'Gun. I don't know the snubby speed but they do get just over 1300fps from a 5.5" Ruger Single Six. I am guessing they pass the 1000fps mark in the snubby. Any idea what the recoil would be from that 13oz gun? It weighs 15oz fully loaded.

The recoil isn't bad but the muzzle blast is right up there with a 357 load.

I really like my 32 caliber revolvers. With 100gr lead bullets loaded to 850fps they are like shooting a 22 mag snubby. And the 850fps was from a 2" model 30-1. These ain't your Grampa's 32 long loads. That gun weighs around 20oz.

 

[bluejeans]

These are S&W 9mm clips. They needed slight modifications to hold the smaller .380 ACP rims.

Can you elaborate on how you modified the clip? Perhaps you used the “slits” model and bent the fingers inward slightly?
I am interest to try this but wasn’t going to modify a j frame for it yet… then I realized that my 627 is cut for moonclips and I should be able to use a 929 clip to do the same thing.
My interest is just for plinking with the kids because I have 10’s of thousands of .380 projectiles and no gun to shoot them.

 

[Jim Watson]

I was wondering about that, too.
I once had a 686 cut for clipped .38s only to find that the dash number mattered and my clips did not match my cylinder. I spent a lot of quality Dremel time grinding the notches a bit.