Author Topic: .25 Disco fever.... add another project to the pile (Read 38923 times))

rsterne · « **Reply #80 on:** September 30, 2011, 04:29:24 PM »

Actually not too bad at 50 yards for just the first pellet.... It will be interesting to see how it groups with JSB Kings and EunJin Domes.... My bet is on the Kings.... You can also try the 31 gr. RWS Superdomes and the 26 gr. Predator Polymags.... I have some of each but have never done any accuracy tests in .25 yet.... So far, everyone shooting a quarter-bore at the longer ranges raves about the accuracy of the JSB Kings....

BTW, how much velocity are you gaining from the 30" barrel compared to 24".... I know you can figure that out (and probably have).... Did you know that you can get a 23.8" long choked Lothar Walther barrel in .25 cal that is only 12mm OD? (special order).... just requires a skim off it to fit the breech and it still clears the main tube (barely).... That is what I have on my .25 Disco....

Bob

lloyd-ss · « **Reply #81 on:** October 02, 2011, 09:25:21 AM »

Bob, yes, the diff between 25" and 30" calcs to be only 40 fps. I have a 16mm (.630) x 25" LW .25cal barrel in my stash. It's the one I used in the max velocity video from 2008. Not sure what I am going to do.

The 30 " barrel seems excessive and right now I have it secured and cushioned with some Sorbothane and I am not too confident in its stability, but it seems too whippy for free floating, I think. I ought to try and zero in on its accuracy capability in this long barrel configuration first.

I could see maybe going to a tall breech and a .25 cal rotary magazine, with the .630 dia .25 cal LW barrel and an LDC. That would probably be a sweet setup,

but it is really a $$ commitment, too.
But I have been neglecting the big bore stuff and that wants some $$ and hours, too. [Funny, that almost sounded like what I say at work, and I want to keep it fun.

] Anyway, got numerous directions to choose from, so I will just see how it evolves.

Oh, and I have at least one more mod to make to the valve head configuration in this thing to see if I can wring any more out of it.

Lloyd

lloyd-ss · « **Reply #82 on:** November 19, 2011, 10:54:42 AM »

This is the first of a series of 4 videos about how I did the modifications. Much of the info is already in this thread, but the videos tie it all together (and you don't have to read

).

This first video is a demonstration of the .25 caliber power and is also ion the PCP gate, but I wanted to have all 4 videos in the same thread for continuity.

Video number 1.
.25 cal Disco Power Demo

lloyd-ss · « **Reply #83 on:** November 19, 2011, 10:57:26 AM »

Video number 2.
.25 cal Disco Pellets and Hammer Springs and Adjuster

lloyd-ss · « **Reply #84 on:** November 19, 2011, 01:35:37 PM »

Video number 3
Hammer assembly, breech, barrel, and the second air tube

dk1677 · « **Reply #85 on:** November 19, 2011, 04:46:17 PM »

Lloyd you da man!

lloyd-ss · « **Reply #86 on:** November 19, 2011, 05:34:48 PM »

Here we go! This is the last one.

Video number 4
Air Tube and Valve Assembly

0351_Vet · « **Reply #87 on:** November 19, 2011, 05:37:38 PM »

Read 1449 times........Today at 01:34:48 PM

I rest my case, the Man is a Master. Great Video's Lloyd.

rsterne · « **Reply #88 on:** November 19, 2011, 09:03:57 PM »

Great videos, Lloyd.... Interesting how different your prototype valve is from the production Disco one.... with the screw in ends retaining the screen and the O-ring.... I even have one Disco valve without any O-ring seal on the stem!!!.... The production valves are aluminum, of course as well....

Bob

lloyd-ss · « **Reply #89 on:** November 20, 2011, 09:29:50 AM »

Bob,
Yes, there have apparently been variations over the years. My Discos are older plus many of the parts in the video are my fabrication. With the exception of the barrel, someone with good shop skills and a lathe and mill, and lots of time, could build something similar from scratch. Or even better, as you have done.

Rescue35 · « **Reply #90 on:** November 20, 2011, 12:23:45 PM »

Quote from: lloyd-ss on November 20, 2011, 09:29:50 AM

Bob,
Yes, there have apparently been variations over the years. My Discos are older plus many of the parts in the video are my fabrication. With the exception of the barrel, someone with good shop skills and a lathe and mill, and lots of time, could build something similar from scratch. Or even better, as you have done.

It is amazing how simple of a design these rifles are. Great example of the KISS philosophy at work.

lloyd-ss · « **Reply #91 on:** November 20, 2011, 06:07:13 PM »

General Disclaimer

Hey Everyone,

Thanks for all the comments and encouragement, but I do want to make just a few general comments on the subject of modifying airguns.

As I have said many times, if I couldn't work on airguns, I probably wouldn't own them. And by work on them, I mean try new and different things. Its about the creativity and the learning. I like to learn from what other people have done, but I usually dive in and try something my own way first. Later I might find out that it has already been tried, and that there is a better way. No big deal, I learned something anyway.

As I said at the beginning of video number 3, there are a lot of folks out there that know a lot more about airguns and have a lot more experience than I do. I have learned a lot from them. They have tried and true methods that not only work for them, but will work for other people, too. I am sure that some of my modifications make them shake their head. That's fine. My methods work for me and serve my purpose, but are definitely not for everyone. I like the results (mostly

), but others might not have any use for them. It's about the challenge of making something better, and that is my interpretation of "better".

So take what you what you want from what I have presented.

A guy I used to work with did automotive work on the side. Mostly custom modifications and difficult repairs, special stuff. His guarantee was, "30 seconds or 30 feet," but he had a long waiting list of customers. And he never lost his love of working on cars.

I'm glad I have airguns, and all the good folks of the GTA.
Lloyd

airpuffhunter · « **Reply #92 on:** November 20, 2011, 07:27:59 PM »

lloid thank you for the videos
lots of info in there

john · « **Reply #93 on:** November 20, 2011, 08:57:51 PM »

Quote from: airpuffhunter on November 20, 2011, 07:27:59 PM

lloid thank you for the videos
lots of info in there

^+1 really helps us newbies understand how these things work.

0351_Vet · « **Reply #94 on:** November 20, 2011, 09:13:15 PM »

Quote from: lloyd-ss on October 02, 2011, 09:25:21 AM

Bob, yes, the diff between 25" and 30" calcs to be only 40 fps. I have a 16mm (.630) x 25" LW .25cal barrel in my stash. Not sure what I am going to do.

I could see maybe going to a tall breech and a .25 cal rotary magazine, with the .630 dia .25 cal LW barrel and an LDC. That would probably be a sweet setup, but it is really a $$ commitment, too.

Lloyd

Lloyd,

I think you should just build it for me in the 25", (and apply that money to towards your BIG BORE projects that were put on hold, whilst perfecting this here beauty).

I have a brand new (DOD) "Disco Organ Donor" just waiting for surgery from "Dr. Lloyd".

Man, I love this thread.

Walt

Rescue35 · « **Reply #95 on:** November 21, 2011, 10:06:00 AM »

Hey Lloyd,

On your 30" inch barrel. If you want to lighten it up and let it free float, flute the barrel. Like the barrel on 0351_vet's signature photo.

Here is some more reading I looked up in a hurry. http://en.wikipedia.org/wiki/Fluting_(firearms) You will appreciate the first link in the references on why fluting does not stiffen barrels.

lloyd-ss · « **Reply #96 on:** November 21, 2011, 06:04:36 PM »

I have always liked the look of a fluted barrel. My 30" .25 cal is really a barrel liner ans is only .437 O.D., so not too much extra. The other .25 is .630 dia, so plenty of material. I am wondering how barrel fluting is normally done: before or after rifling, by hobbing or grinding? I don't know but it looks like a lot of work unless you have the right equipment.

I know that when I thread the end of a thin barrel liner, it has the effect of choking the barrel, which is fine at the muzzle, but not at the breech. So I am thinking that getting too thin with the bottoms of the flutes might do something odd (as in - not good) to the rifling. Maybe a little localized decorative fluting, but nothing too serious.

0351_Vet · « **Reply #97 on:** November 21, 2011, 08:21:14 PM »

Quote from: Rescue35 on November 21, 2011, 10:06:00 AM

Hey Lloyd,

On your 30" inch barrel. If you want to lighten it up and let it free float, flute the barrel. Like the barrel on 0351_vet's signature photo.

Here is some more reading I looked up in a hurry. http://en.wikipedia.org/wiki/Fluting_(firearms) You will appreciate the first link in the references on why fluting does not stiffen barrels.

"Typically" the flutes are to increase surface area, to make the barrels less susceptible for overheating. And on most "Sniper" rifles to help prevent "mirage" due to barrel heat.

I too have several AR15/M16/M4 Heavy Barrels that too are fluted. They look Bithin, yet their function has (for me always) been for heat displacement.

The only Barrel Fluting I have seen machined was done on a Mill with a long bed (?) and it was drawn into the bit from one direction to the other. The bed was driven (power), then the barrel re-indexed to the next flute location and then another pass was made.

Sorry, I'm not a machinist so I am sure my terminology is weak.

Also....That was on a bull barrel. On a tapered barrel the setup gets a little more complicated as the bed has to be canted with the rank of the barrel, if that makes sense.

Rescue35 · « **Reply #98 on:** November 21, 2011, 08:51:08 PM »

You are spot on Vet. That is how I would do it. Set the barrel up in an indexer with the barrel running in the X axis. Cut the desired flute and then index by the number of flutes you want.

MustangMike · « **Reply #99 on:** November 24, 2011, 12:55:00 AM »

thanks for posting this now i can pull the valve and gauge port out of my disco for repair

Thank you to our advertisers!

.25 Disco fever.... add another project to the pile

Author Topic: .25 Disco fever.... add another project to the pile (Read 38923 times))

0351_Vet

0351_Vet

0351_Vet