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PracticallySane
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Tue Nov 24, 2020 7:37 pm

Hey guys, its been a very long time. I previously used the name "*###*" I lost access to my account and it seems I'm sol as far as recovery is concerned.

I have built many more great toys over the years and I felt like getting back into the community to share my knowledge as well as to learn and become better my self.

This is my greats feat so far.

It has 50cal muzzle loader barrel rifled 1:70 from green mountain rifle barrels.

The main components of the rifle are 3/4" 3000 psi hydraulic plumbing. The 3/4" street tee has a 1-3/4 male male adaptert. A 1" cap drilled and tapped to fit a 1/4 nipple and reinforced with jb weld(the only component not rated to 3000psi at the time of writing).

It is operated by a custom spool valve made from a brass street t and a 1/4 cap. (At 3000 psi even a shreader valve take 250 pounds of force to actuate)

The operation is what I'm calling a spool valve opposed to a piston due to the fact I am using oring seals instead of a sealing face.

The piston is machined from aluminum round stock.

The rifle stock is from a ruger 10/22. I had it laying around and it fit, so why not?

I dont know of i covered everything. If you have any questions let me know.

I'll let the pictures day the rest!

Sorry for the random order of stuff.
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I’m a scientist; because I invent, transform, create, and destroy for a living, and when I don’t like something about the world, I change it. ~Rick Sanchez.
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Xamllew
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Wed Nov 25, 2020 11:05 am

That's very nice, I always like seeing rifled barrels on homemade airguns. Tell us about the performance.
PracticallySane
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Wed Nov 25, 2020 6:20 pm

I'm shooting 360 grain slugs at the moment. At 1800 psi it shoots clean through 2" plywood. No hesitation at all. At 3000 I feel like it could drop a grizzly bear. A chronograph is pretty high up on my list but currently I dont have any actual number for performance.
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I’m a scientist; because I invent, transform, create, and destroy for a living, and when I don’t like something about the world, I change it. ~Rick Sanchez.
PracticallySane
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Wed Nov 25, 2020 6:25 pm

Here's what I'm shooting.
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jackssmirkingrevenge
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Wed Nov 25, 2020 11:48 pm

Welcome back and nice work! What pressure are you running it at?

With a rifled barrel and the availability of commercially made projectiles it seems a shame not to have a sight on it.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Thu Nov 26, 2020 9:06 am

I usually shoot at 2000 psi. The pilot volume is almost non existent, so it opens with a sharp bang.

I am currently figuring out how to go about attaching the sights. But honestly its fairly easy to aim as is. Although it would be cool to see the performance at 50-100 yards.

I'd put this thing up against a texan without question.

Next step is a hybrid clone.
I’m a scientist; because I invent, transform, create, and destroy for a living, and when I don’t like something about the world, I change it. ~Rick Sanchez.
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jackssmirkingrevenge
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Thu Nov 26, 2020 10:41 am

PracticallySane wrote:
Wed Nov 25, 2020 6:20 pm
I'm shooting 360 grain slugs at the moment. At 1800 psi it shoots clean through 2" plywood. No hesitation at all. At 3000 I feel like it could drop a grizzly bear.
It probably could... 360 grains at say 1000 fps is 800 ft lbs of energy, and people have been dropping buffalo with that sort of performance.
A chronograph is pretty high up on my list but currently I dont have any actual number for performance.
I just received one of these, dirt cheap and apparently works very well. Will do a thread about it when I have time to check it out.

Image
I am currently figuring out how to go about attaching the sights.
Nothing wrong with attaching a rail using hose clamp, it's good enough for Heckler & Koch!

Image
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Thu Nov 26, 2020 10:56 am

I have been curious about the barrel chronograph, but I am seeing the traditional style as low as $70 on ebay right now. I might just go ahead and order one...

Maybe I'm just over thinking it but I have a tig welder and was thinking I would make something pretty.

I'll definitely check out what you find out with that contraption up there.

FX makes this thing but its a little steep at the moment.

https://www.pyramydair.com/s/a/FX_Radar ... graph/9078
I’m a scientist; because I invent, transform, create, and destroy for a living, and when I don’t like something about the world, I change it. ~Rick Sanchez.
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jackssmirkingrevenge
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Thu Nov 26, 2020 11:17 am

I was tempted by the FX but this is what put me off:
Velocity Range: < 335m/s (1099fps)
Basically useless for supersonic projectiles.

edit: just did a test comparing the cheap-o chrony to my F-1, using an airsoft rifle firing 0.25g BBs firing 5 shots each:

F-1 (feet per second) 402.7, 396.5, 400.4, 399.7, 398.6 - average 399.6 fps / 121.8 ms

Cheapo Chrony (meters per second) 121, 121, 121, 120, 121 - average 120.8 ms / 396.3 fps

Looking very promising, and unlike the F-1 it doesn't care about fluorescent lighting!
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Thu Nov 26, 2020 12:05 pm

Thats awsome. What is the maximum velocity on the cheapy?
I’m a scientist; because I invent, transform, create, and destroy for a living, and when I don’t like something about the world, I change it. ~Rick Sanchez.
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Thu Nov 26, 2020 12:07 pm

I launched a few arrows out of this thing. I got about 8" penatration on a old telephone pole at 2000#.
I’m a scientist; because I invent, transform, create, and destroy for a living, and when I don’t like something about the world, I change it. ~Rick Sanchez.
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Thu Nov 26, 2020 12:23 pm

I just pulled one up on ebay. It says max velocity is 999m/s which is about 3277 fps. It also say max energy of 800 joules which is 590 ft/lbs.

3277 fps with an energy of 590ft/lbs is roughly 1.6 grain projectile?

I am guessing more than 800ft/lbs on my rifle. Im not sure how there is a maximum energy for something that measures speed?
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jackssmirkingrevenge
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Thu Nov 26, 2020 12:24 pm

PracticallySane wrote:
Thu Nov 26, 2020 12:05 pm
Thats awsome. What is the maximum velocity on the cheapy?
999 m/s , so unfortunately not good enough if you're firing Panzergranate 40 from a Panther's 7.5cm KwK 42, put probably good enough for most amateur applications ;)

Shooting window width is around 35mm, and it's a short distance so I've be comfortable shooing say a 20mm projectile through it.
I am guessing more than 800ft/lbs on my rifle. Im not sure how there is a maximum energy for something that measures speed?
I guess they copy-pasted the description from another model because there's no programming or mode button as far as I can see, it only measures speed in meters per second so there is no limit to energy.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Thu Nov 26, 2020 1:24 pm

Well I went ahead a ordered one. Here in a week I should I have it at my door. I cant wait to see some numbers.

Did some more shooting. Decided to put the slug in backwards as a hollow point. 2200#. This is a piece of 2" plywood. Can I upload videos here?
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jackssmirkingrevenge
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Thu Nov 26, 2020 1:46 pm

PracticallySane wrote:
Thu Nov 26, 2020 1:24 pm
Did some more shooting. Decided to put the slug in backwards as a hollow point. 2200#. This is a piece of 2" plywood. Can I upload videos here?
Impressive!

There is no direct video upload but video links like say youtube will be automatically embedded.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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