First post, First BBMG

[kustomkb]

I was browsing youtube and saw a BBMG video which inspired me to build my own. Internet research led me here where I found more inspiration and ideas. I just made mental notes as I was browsing so please forgive me for not giving due credit to the individual threads which I drew my inspiration from.

I am a machinist by trade as well as my hobbies which are mostly spent building model engines.

Well here it is. If some one has some information about adding an adjustable hop up I would appreciate it. I also plan on adding a stock.













[youtube][/youtube]


Have fun!

Kevin

[mark.f]

That is beautiful.

However, it sounds like you're having some feeding problems. Have you considered a shroud for the vortex block?

[jackssmirkingrevenge]

Clucking bell!

Way to make an entrance I can see the model engine pedigree too.

As mark says though it does seem to be misfiring.

I wouldn't bother with hop-up for what is essentially a BB hose.

If you want more range, use heavier projectiles and add pressure

[warhead052]

Wow, looks incredible! Try heavier projectiles and more pressure like jack said, you might like the effect it has at 100-200 feet. And add a bb shroud to keep it from jamming. But other than that it looks great! Welcome to spudfiles!

[Crna Legija]

wow hope their wasn't fishes in that pond .

looks great, that plastic chamber looks realy thick so you should be able to crank the pressure right up

[evanmcorleytv]

Whoa! Nice vortex block! But, as stated earlier, you really need to use heavier BB's, and add a shroud.. I would also add a powerful spring, and a large O-ring to your plunger, so it's air tight, and efficient.

[kustomkb]

Thanks a lot fellows!

"BB hose" I like that, That pretty much sums it up. I thought the hop-up added back spin to stabilize the BB's.

The spring I had on hand for the plunger was a bit too heavy so it was left out for the initial test. I was supposed to draw the plunger in by hand as the gun was firing but in my excitement, (the video's are the only time the gun has been fired since I only had a few bb's) I forgot to pull the plunger in, which left some dead space, which caused the misfiring, I hope.

By shroud do you guys mean the side plates to cover the big bore of the vortex block? It may be hard to see in the video but there are some on there. They can be seen at the top of the 4th picture. They cover about 2/3rds of the bore. Would more or less be better?

I thought about adding an o-ring to the plunger but the shaft is a nice sliding fit in the brass bushing of the front cap. But I guess every bit helps. I'll give it a try.

I used a valve from a blow gun and I might try drilling out the vent hole to allow more volume of air to pass through.

I just picked up some .2 gr BB's from the hardware store, the heaviest they had. But man, this is going to be an expensive toy. There must be cheaper on-line suppliers? I'll try them out in the morning.

The barrel is 3/8 tubing with a .065 wall thickness. This leaves about 5 thou clearance all around the BB. I guess a tighter fit would up the velocity?

Thanks again for all of the comments and suggestions!

Kevin

[cannon monkey]

hey Kevin love your work i just signed up for school to be a machinist

[jackssmirkingrevenge]

I used a valve from a blow gun and I might try drilling out the vent hole to allow more volume of air to pass through.

MOAR FLOW = MOAR POWAH, especially given your relatively larger BB chamber. Still, I doubt you would see an amazing difference.

I just picked up some .2 gr BB's from the hardware store, the heaviest they had. But man, this is going to be an expensive toy. There must be cheaper on-line suppliers? I'll try them out in the morning.

There are more complex designs with more power per shot and lower rate of fire which you might want to consider.

The barrel is 3/8 tubing with a .065 wall thickness. This leaves about 5 thou clearance all around the BB. I guess a tighter fit would up the velocity?

Not to a large degree, it's already a good fit.

Have a look throughthis thread

[wyz2285]

You need a better barrel, and seal the chamber by adding o-rings on the components so the pressure can build up inside the chamber.
Besides that, best bbmg vortex I have ever seen.

[jrrdw]

Nice work! Try Ebay for ammo, I got 400 1" super balls for 20 dollars. Had to go through the listings but found the deal. I think the misfiring will stop once you get the plunger spring figured out.

Welcome to Spudfiles!

[kustomkb]

Thanks for the comments and suggestions fellows.

Thanks cannon monkey, I hope your school goes well, it's a good trade.

Check out these links if you want to see some more of my machinist projects;

Photos;

http://picasaweb.google.com/kustomkb

Videos;

http://www.youtube.com/user/kustomkb#g/u


I have been really busy working on my house but I did find time to add a stock;







Thanks again for everybodys input. When I find some time I will try to implement some of your suggestions.

I did try some .12g BB's, the heaviest the hardware store had, what a difference!

Too many hobbies, too little time...

-Kevin

[warhead052]

:O Looks like a shotgun. Very nice!

[jackssmirkingrevenge]

Check out these links if you want to see some more of my machinist projects

Oh fap fap fap...

Damn I wish I had a lathe and mi....er... damn... need a new excuse. I wish I didn't procrastinate so much!

I did try some .12g BB's, the heaviest the hardware store had, what a difference!

0.12, are you sure? They're the lightest I know of. You want something like this

[kustomkb]

Thanks guys!

0.12, are you sure? They're the lightest I know of. You want something like this

Ha ha, boy do I feel silly, the new ones I got weigh the same as the original!

The orange ones were shiny and very round. The black ones are chalky and lumpy, like peas. I wonder if the irregular shape made them fly better. Like a dimpled golf ball?

.43 would sure pack a punch!