German anti-tank rifle,WWI

[DARIVS ARCHITECTVS]

THIS Is some really COOL STUFF, amafrank. Thanks!

[Michael J]

Curse you canadian laws! I do not believe A/T rifle rounds to be legal here, while the rifle itself may be though... Basically, i might be able to buy one, just never shoot it .

I love the pictures guys, all these cool things . I should come over for a visit one of these days !

[DARIVS ARCHITECTVS]

A/T guns are legal here in the US, but there just aren't enough tanks around to shoot at.

[amafrank]

I heard that MarStar brought a bunch of PTRS's in to Canada last year and a lot of guys down here were mighty pissed when they found out they couldn't import them into the US. Between the Canadian stupidity and the US stupidity there is still some room for the odd allowable piece or two. We just can't mix them together for max fun.

Frank

[DARIVS ARCHITECTVS]

Canadian stupidity and US stupidity can make for ONE HUGE PILE of stupidity.

[BigBoy99]

Was the aluminum case something needed sepecifically or was it just a cost saving method?

I hand made the aluminum cases because of the price of brass. Machining a cartridge case from round solid brass bar stock gets to be VERY expensive when about 90% of the brass ends up in the scrap bucket. The aluminum cases are proof of concept. If they work and fire the rounds, then I'll work on a design to modify 50 BMG brass cases to work in the gun. I have found a place in Austria the makes new 13mm brass casess for the M1918 Mauser but they are asking $50 per single cartridge case plus shipping. I can do a lot of experimenting for that kind of money!

Bill

[amafrank]

We can't really discuss govt stupidity too much or we will all be angry and crying.

here is a pic of the boys rifle. This gun was originally shipped to Finland in one of the two shipments of 200 guns ea. The gun when I got it had the barrel cut off and a bar welded in the chamber. I made up a barrel in US .50 cal and she's a shooter again. We've fired somewhere around 1700rds through it so far and the throat is eroding bit. I'll have to set the barrel back and rechamber soon though accuracy doesn't seem to be too badly affected yet. A friend and I were shooting 4" groups @ 200yds with GI tracer ammo so it is pretty good still. We have taken the gun out to Colorado a few times and shot at targets over 1800yds away. The target is a big steel tank from the oil fields. Its about 4ft in dia and 20ft long but hitting it is not easy with open sights graduated to only 400yd. A lot of "kentucky windage" is required but still its possible to consistantly hit that tank at that incredible range.



The last pic here is an ammo comparison. From left to right, 60mm training/practice round with a loaded fin assembly below. The fins screw into the bomb body and can be readily changed in seconds. Next is the 20mm X 138B round for the Solothurn or Lahti A/T rifles, the 14.5mm API (B32) round for the KPV and if downloaded slightly for the PTRS, and last the little .50 cal US API for the Boys rifle.



Hope you guys like the pics.

Frank

[noonxnoon]

Frank,

For your smoke mixture, have you tried potassium nitrate(saltpeter) and sugar?

I think that is the correct term for saltpeter. You can buy it from the drugstore.

Back in KS, we used to mix saltpeter and soap to make slowburning fuses...you mix saltpeter and sugar and when it burns it gives a pretty decent smoke.

The primer on the mortar round looks like a shotgun shell! I take it the primer is much more powerful then just a 12gauge shell??

btw...how heavy IS that 20mm round?? looks like something you put in those big mortars...the ones that have the feet that you imbed in the ground!

What is the recoil like for the 20mm?

[noonxnoon]

BigBoy99,

Are you machining all this stuff on a metal lathe?

Pretty cool to be able to make your own shells. Not sure how much the raw material cost...but if you were to make brass cases, you are confident in it being strong enough to handle the charge pressures?

I imagine you know quite well what you are doing, but it all kind of blows my mind to be honest!

I'd love to be more 'self-suficiant' with things like this. Been wanting to take a gunsmithing course...learn how to reload ammo...etc etc...

time and money!

[Michael J]

Canadian stupidity and US stupidity can make for ONE HUGE PILE of stupidity.

Don't even get me started on stupidity , i don't want to hijack this thread, but lets just say it includes marstar.

@ Frank:
They never had it advertised on their website... mind you, doubt i'd be able to afford it anyways, and a very good chance i doubt i'd even be able to purchase it either . Some of these guys at marstar are real, well... "special", in terms of them not being able to get their facts straight, and stories right .

[amafrank]

Michael I know exactly what you mean about the MarStar guys. Having dealt with them a little there is no need to say more.

Noonxnoon, we have tried a few smoke mixtures, the potassium nitrate and suger mix was suggested and tried in small quantities but it has some problems with ignition and cleanup of the residue. We want to use the bombs more than once without sand blasting the goop out. We are trying to get a good HC smoke mixture from a local pyrotechnic guy as I don't want to mix my own if I can get it from a Pro.
The primer in the 60mm is a shotgun primer type 209 which is the standard unit used in everything from the .410 to the 8ga. There is a powder charge in the shell as well as the primer and the main lift is the powder charge. The shell cases we use are 20 ga and they are cut down in length to fit the fin. The powder is measured for each charge and there is a hard wad in the mouth of the case. When the shell is pressed into the fin the wad sits against the front (top) of the fin. The plastic shell actually blows out at the holes that you see in the sides of the fin body and the powder gas vents into the mortar barrel. That is what propels the bomb. The bombs have what are called obturation grooves in them to seal the bomb by creating turbulance that prevents the gas from blowing by the bomb. When we reload the fins a punch is put through the front end of the fin and the hard wad is tapped down til it hits the base of the shell case. At that point a good solid hit will push the case out of the fin. When they are removed the shells have holes in the sides that correspond to the holes in the fin body and they can't be reloaded. The US 60 and 81mm mortars use shotgun type shells for propulsion. The 60mm uses 20ga and the 81mm uses 12ga. Mortar crews were issued boxes of shells for loading fins though I'm not sure why since the fins were packed with the mortar bomb and were loaded with the main lifting charge to start with. I guess maybe they reloaded dud rounds or something....

Thats it for now
Frank

[amafrank]

Frank,

btw...how heavy IS that 20mm round?? looks like something you put in those big mortars...the ones that have the feet that you imbed in the ground!

What is the recoil like for the 20mm?

Sorry, I forgot to answer this part....

The 20mm round uses a 1500 grain projectile from the US 20mm vulcan round. They are hollow steel projos with an aluminum nose swaged in and a bronze driving band. For your reference there are 7000 grains in a US pound. I don't know what the weight of the complete loaded round is but its nowhere near the 60mm weight. The projos are relatively cheap compared to the brass ones I was making and cost to reload a round including powder, primer, projo and the cost of the shell case averages out about $10 a shot. Recoil on the gun, the Solothurn anyway is hard to describe because the gun is so heavy and it uses a pretty effective muzzle brake. The gun has more of a shove than a kick. Its unlike any other rifle or shotgun I've fired but the 12ga with slugs is probably the closest. My little wife shoots the thing an can actually hit stuff with it. I used to have one of the Finnish Lahti anti-tank rifles and it was gas operated where the Solo is recoil. I think the lahti had a sharper kick. The solo has a 43 lb barrel that moves about 4 inches when the gun fires so that absorbs a lot of energy.

I hope that answers the questions.

Frank

[noonxnoon]

I guess thinking about it, you burn sugar and it carmalizes!

We used to make balls of it or burn it out of a can...never shot it!

As for the primer...I guess you could use near any primer as long as you got a booster to boost it!

$10 a shot...that is about like 50 cal shooting or buying commerical .458 Lott rounds!

I'd love to get a rifle that can shoot the Lott...amazing energy that thing has...but the cost per round...wow!

Do you shoot a 50 cal? I'd like to get a 50 cal rifle, but again...the cost of ammo!

Thanks as always for the info.

What other exotic firearms you got??? flamethrower?? nebelwerfer??? one of those experimental sound guns???

[Michael J]

... one of those experimental sound guns???

I got me a darned alarm clock that is as loud as heck , i figure if i let it go off, it would simply drive the enemies insane, and induce suicide, or blow their heads up completely.

[noonxnoon]

Michael,

paint that clock green, spray on a WWII stencil and try to sell it on GB

[DARIVS ARCHITECTVS]

one of those experimental sound guns???

My stereo qualifies....

[noonxnoon]

I see the sound gun comment is making the peanut gallery come out of the woodwork!

On a serious note to Frank!

What about castor oil? I've never burned it, or rather heated it up...but I know you heat castor (or caster) oil up and it smokes like heck.

not sure if that would leave a residue. Maybe have the same gumming problem saltP & sugar.

I remember reading in the PMJB about making a smokescreen from your car's exhaust by dripping caster(or castor!) oil into the exhaust manifold and the heat from that causes the oil to smoke big time.

So Frank, tell us...did you ever get that WWII-cira railgun working??? I know you got to have one in your garage somewhere!!

Did the V-2 rocket ever take off? :P

[amafrank]

Well the rail gun is a secret project so I can't discuss that....
I never thought of castor as its not really very self contained. When I grew up and worked for a crop duster he had an oil injection system that pumped hydraulic oil into the exhaust to make smoke. It created a very heavy cloud for marking his passes on a field. Its not really a good way for smoking mortar bombs though...

I do have a fifty, its in the picture about 4 posts back, the Boys rifle. Its much cheaper to shoot then the 20mm. Projos are about 20-50 cents ea, primers about 25 cents and the powder around the same cost. Brass is good for 10 or more shots in the Boys rifle, it has a nice tight chamber. So total cost per round on the .50 is around $1 or so per round. I reload for this one too. When the rifles are this close to your face the trust level in someone elses work is too much for me. I do my own stuff. The cost is really not as bad as it sounds when you compare it to other recreational activities. What does a movie cost to go to now? How about boats, cars, dancing and drinking and any number of other pastimes we engage in? For my money the shooting is more than reasonable and I get to do all sorts of experiments like seeing if the 20mm can put a hole all the way through a car front to back. The answer is yes, it can. Brass solid 2350 grain projos of my own design and manufacture fired at about 2400 feet per second from a range of 100yds will penetrate the whole car and an aluminum engine block with the crank and internals still in place. The engine was pretty well wasted by the time the projo came out the front. (we fired at the license plate in back). Some of the stuff is tax deductible for me since I am in the business of repairing, manufacturing and transferring NFA firearms. Testing and experiments are part of the business.....
Someone has to do it and it might as well be me.

Frank

[Bil]

Some guys have all the fun!! I am just glad someone does,and shows up for 'show and tell'Thanks for the pics and info,frank! ---bil

[noonxnoon]

Yeah Frank,

I'm with Bil.

Can't appreciate what you got enough.

As I said, really off the grid stuff that you generally never see in a non-direct military context.