7.8x19mm. Because, uh, Reasons.

What the world really needs is a .30-caliber pistol cartridge that, while more powerful that .32 ACP, is not so powerful that it requires a locked breech…” said no one ever. Not even me, and it’s my idea. It’s not even a new idea; the French had a .32 service cartridge that was rather similar. Hmm… better run it through the Wildcatter’s Checklist:

*Does it duplicate the performance of an existing cartridge? Check!

*Does it answer a question no one is asking? Check!

*Is it a pain in the butt to make? Check!

*Is it of dubious utility? Check!

*Will it be fun? Check!

Oh look, a perfect score! I guess we’d better get on with it then. Ladies and Gentlemen, I give you… drumroll please… the 7.8x19mm Auto!

75gr LFP and 65gr JHP versions, though I’m contemplating a 100gr bullet as standard. Have to see what I can come up with…

A couple years back someone gave me some .30 carbine brass, and it was inevitable that I’d find something to do with it sooner or later. Shortened and resized is turned out to be a pretty perfect donor-cartridge for the 7.8x19mm.

Umm… why 7.8mm? Well, because it turns out the .308 bullets are actually 7.82mm in diameter, not 7.62mm. No, I don’t get it either, but that’s the way it is. OK, why 19mm long? Because for the methods I had on-hand it was easy for me to shorten them to that length. I was shooting for 20mm and got 19 and said, “good enough.”

Of course I’ll need some way to test it, and as it happens I have a Maadi Helwan pistol converted to a .380 ACP straight-blowback already, and guess what new cartridge fits in a 9mm Helwan magazine?

Yep, the 7.8 fits in a 9mm Helwan/ Beretta M1951 magazine. It also cycles from the magazine, chambers and extracts from the .380 barrel.

OK, the 7.8 fits in the magazine, and it feeds, extracts and ejects from the .380-chambered barrel. So if I bore out the barrel, line it with a .308 barrel liner and cut the chamber for the new cartridge it just might work…

The goal here is to see if I can drive a 100gr. bullet to 1000fps. and still operate safely as a straight-blowback. This will yield 222 ft./lbs of energy at the muzzle, and the bullet’s high sectional density ought to give it excellent penetration, hopefully even with an expanding bullet.

The stock 9mm magazine positions the bullet well for feeding into the chamber, the extractor holds the case well and the ejector kicks it out. Now all I need is the right caliber barrel…

As it happens I have a short section of .308 barrel and some Speer 100gr. .308 Plinkers. I also have a .308 resizing die I use to resize .312-caliber bullets to .308 for use in my Mauser C96 broomhandle. This is a totally doable thing…

Of course the question of whether one should do a thing just because one can comes up… to which I say, ‘Why the hell not?’ It’ll be fun, and if it doesn’t work out I can always get another barrel for the Helwan and turn it back into a .380, or even get one of the new locking blocks from that fellow in Europe and restore it to 9mm.

So is this new cartridge going to set the world on fire? Uh, no. The world manifestly does not need this cartridge. I expect I will go to my grave as the only person to own a firearm chambered for it, in fact. But it will be fun, and that’s really the whole point.

Naturally whatever happens I’ll keep you posted.

Michael Tinker Pearce, 23 January 2021


Gilding the… Dandelion?

I have some handguns for specific purposes. I have a long-barreled .44 Magnum for hunting. I have a number of smaller guns for concealed-carry, and some just for recreational target shooting. Most of them aren’t quite as specialized as my Taurus Model 415 .41 magnum. That’s my, ‘Peeing-in-the-woods-oh-crap-is-that-a-bear?!’ gun.

The Taurus Model 415 .41 Magnum. Matte stainless finish, 2-1/2″ ported barrel and recoil-absorbing 1-piece neoprene grip.

There isn’t much chance I’m going to run into a dangerous animal in the woods while hunting, but it could happen. It makes sense to have a carry gun; something powerful enough to deal with an irritable or inquisitive Black Bear.

To be clear, this is not a ‘hunting handgun,’ it’s a sidearm to carry while hunting, just in case. IN Washington state a handgun used to hunt big game must have at least a 4″ barrel, so this one is right out of the running.

So, relatively small, only slightly larger and heavier than a S&W K-frame but firing a very powerful cartridge. Easy to carry, doesn’t get in the way too much… but it kicks hard. The stock grips do a pretty good job of making the recoil tolerable, but they are a bit ‘sticky,’ tending to grab clothing, and the squishiness of them isn’t ideal for control in rapid-fire. I made a set of custom grips, and while they impart excellent control they are painful with full-power loads. That’s a compromise I can live with; I mean, it’s not like I am going to care if I need to use it. But if I could come up with something better…

The custom grips on the Taurus. Excellent rapid-fire control, but not at all comfortable doing it.

A couple of years ago a friend gave me a set of grips for a large-frame revolver for Christmas. Very fancy, with black enamel and mother-of-pearl inlays. I have a large hand, so these worked out nicely. Some time later I sold that gun, but I kept the grips. I mean, I was bound to get another gun they fit sooner or later.

I ran across those grips last night and thought, ‘I wonder…’ The thing is the Taurus is based on their Tracker revolvers, meaning it has a non-ergonomic grip-frame; one piece grips are slipped on over the frame and secured with a screw at the bottom of the grip. So they might fit, but they’d need some adaptation to secure them.

The solution was pretty simple; I cut some wood pieces and glued them into the grips to properly surround and secure the tang.

The wood inserts secure the grip-frame nicely. The circular piece in the center secures the grips against slipping out.

So, quite a good fit and provides a really nice grip. But it seemed out of place against the matte stainless finish of the gun. OK, that’s easy enough to solve; some buffing, some 3000-grit sandpaper and Flitz metal polish and the now-shiny gun looks much better with the grips.

I left the top-strap matte; there are some bits you don’t want to be shiny.
Since this gun is meant to be deployed in a hurry I cut away the right side if the front of the trigger-guard so my trigger-finger can move between a safe position on the frame to the trigger more quickly and easily.

So, How’s it Shoot?

Better than I do, but that’s not unusual. The large grips have done the trick; while recoil with full-power loads was not what I would call pleasant it wasn’t bad, and with .41 Special loads (210gr. LSWC @ 900 fps.) it was downright tame. I mean, relatively speaking. This gun consistently shoots high and right; I’m likely to modify the sights.

,41 Special, 1 shot per second at seven yards. Shooting high and right, as usual. I think it’s time to make an adjustment to the sights.
Full power .41 magnum loads, rapid-fire at seven yards. Aim point was 6 o’clock.

OK, But… Why?

Not many people will bother to work on a Taurus, and the reason is simple; they can be an iffy proposition. Quality control on Taurus has been… let’s call it whimsical. Generally the Model 85s are consistently good, and some of their new semi-auto pistols are well regarded. Others are catch-as-can; if you get a bad one it’s bad. If you get a good one it can be very good indeed. This irregularity has caused people to regard them, somewhat unfairly, as junk.

This is a good one. But leaving that aside the question remains; why spiff up a working gun like this? My response is, why not? Why shouldn’t I have a ‘fancy’ gun as a sidearm for hunting? I’m not stalking perps through dark alleys; it doesn’t matter if the gun is reflective or has fancy grips. If the gun is holstered the shiny bits are covered; if I need it the shininess is irrelevant.

Anyway, it’s my gun, it’s cool and I like it. Good enough.

Michael Tinker Pearce, 18 January 21

Return of the Velodog!

The other day I picked up some .22 Hornet brass intending to make some .251 TCR cartridges. On my way out of Pinto’s Guns Chris asked, “Going to make some Velodog ammo?”

“Nah,” I responded. “Going to make some .251 TCR.”

He nodded, I left and went home. When I got there I thought about it. Making Velodog cartridges from tube and turned down .25 ACP cartridge bases is a bloody lot of work and the results are not really optimal; the tube is just a bit to thick. How would I go about making .22 Hornet into 5.5mm Velodog?

The Velodog with a single round of ammunition.

First I need to straighten the cartridge. It needs to be approximately 5.7mm outside diameter. It occurred to me to try my 5.56mm sizing die. I mounted my .357″ ram, screwed the die into the press and had a go. The result wasn’t bad, but the ram would only go so far into the die. OK, I needed a narrower ram to mount in the press.

Here’s the new ram and die mounted in the press with a case ready to run through the die.
On top is the new, tapered ram. Below is the steel ram I use for swaging .357 bullets.
The standard .22 Hornet case (top) with the case after running through the die.

I grabbed some 1/2″ round brass stock, chucked it up into the lathe and got to work. I used brass because I wanted the manufacture to be quick so I would have more time to refine the design. I put a nub on the face to sit in the primer-pocket to keep the case centered. I tried it in the press and the results were good. I have to remove the case by inserting a rod through the top of the die and tapping it out. As expected it left a fat area around the base of the cartridge next to the rim.

The .223 sizing die. On the upper right is the ram. In the center is a .22 Hornet case. To the right of that is a case after passing through the die. To the right of that is the case with the base turned down to size and cut to length, Furthest right is a loaded cartridge.

So now I had a mostly .22 caliber cartridge. I got a .224″ rod and mounted it in the lathe, slipped the cartridge on to it and pinned it in place with the live center in the primer pocket. I carefully cut away the thick ring of material in front of the rim, then turned the rim down to approximately .300″. I did fifteen cartridges this way.

The cartridge mounted in the lathe. Making these is labor-intensive, but not as hard as making them from tube and .25 ACO cartridge bases.

I used a divider to mark the overall length of 1.15″, then cut the cases off with a cut-off wheel in the Foredom tool. After deburring it was time to load a cartridge… umm, OK; how?

The first problem is priming the case. I don’t have a shell-holder that will work with the reduced rim. In the end I pressed the primer in place with my thumb and seated it with a wooden dowel and a soft-hammer.

OK, load data… uh… there doesn’t seem to be any. I found a forum post where someone had opened an old case and it contained 1.7gr. of powder of an unknown type. OK, Unique was actually around when this cartridge was in common use. I figured I’d try 1.5 grains of Unique. Bullet? Easy-Peasy- I pulled bullets from .22 LR cases. These bullets are nominally 40gr., but they actually weigh .38gr. Pretty close to the 34gr. weight of the original jacketed bullets used in the cartridge.

I don’t have reloading dies for 5.5mm Velo Dog, and the only other dies that work are .22 CCM… which I also don’t have. So I simply pushed the bullet in against the workbench until it was fully seated, and it was too tight to remove or twist. Seemed good enough, and it fit in the chamber. Time to try it. OK, it worked. it went bang and the bullet sank into the gel. I don’t have a velocity for it; the Chronograph has gone wonky because the illumination on one end has gone out. I’ll need to replace some parts. I loaded four more cartridges and fired them into the gel. Average penetration for three shots was 7-1/2″, and one shot fell far short at about 6″. All the bullets tumbled on impact and came to rest base-forward.

The four wound-tracks in the gel. Not a great picture, so I indicated the bullets with red dots. The track on the far right shows the bullet bounced back in the gel, so I have indicated the end of the track rather than the bullet.

All the tracks indicate the bullets were traveling straight on impact. A recovered bullet shows clear rifling marks, so it appears they were stabilized in the bore.

Rifling marks are clearly visible on the recovered bullet.

Ignition was inconsistent; two of four cartridges required multiple strikes before they fired. Federal primers are relatively soft, so I attribute this to the gun rather than the ammunition. Upon examination the un-sprung floating firing pin seems rather short; if I were planning on firing this gun regularly I might address that. I don’t expect to, so likely I’ll just leave it alone.

I think I will spring for the .22 CCM reloading dies though; the Velodog’s younger sibling intrigues me. I might have to chamber a gun for it and experiment.

Michael Tinker Pearce, 6 January 2021