I has semiauto ;-)

[POLAND_SPUD]

judging from my tests 4 RPS are achievable, possibly more... the biggest limitation here is the flexible tubing used (4mm OD by 1.5mm ID) and a bi stable manual override on the valve I use now... I haven't switched to manually operated one yet because because I've been planing to test its full auto capabilities but I do have a manually operated valve

I am not into full auto guns really, well at least not on this gun...
however, I've been thinking of building a high pressure 4.5mm/6mm bbmg with a detent

EDIT
yeah the pressure is low because I wanted to give you comparison between this version and the previous one... you can see vids of it on my other profile on you tube so to get some sort of a reference point (I know it might sound lame but I forgot the password to it)

I'll post higher pressure shots tomorrow... now I am going out to get totally f### ## cya

edit
lol I have to quit drinking

what about damage, what was the target (metal sheet?) and how come the first shot seems to penetrate and the others don't?

yeah the target was a steel sheet (possibly 0,05mm or 0.1mm)

I suppose it isn't exactly the best target for a marble gun... for me all the shots that didn't hit it were much more impressive
I think I'll switch to particle boards or plywood as it shatters nicely

how come the first shot seems to penetrate and the others don't?

pressure drops slightly after each shot so the first shot was the most powerful - that's the only logical explanation I can think of

Accuracy seems to remain all over the place, I can see why you didn't move the camera any closer

LOL true

I am trying to add a hop-up on the muzzle... today I put a short length of electrical tape on the inside of the barrel and it works surprisingly well
I wonder how often it would have to be replaced..? so far it survived about 10 shots
I suppose that something more durable might be a better idea

[jackssmirkingrevenge]

I am not into full auto guns really, well at leass not on this gun...
however, I've been thinking of building a high pressure 4.5mm/6mm bbmg with a detent

Same here, I've ordered me a pressure washer handle to use in conjunction with my paintball tank, if it works well I'll consider upgrading to a 48 cubic inch tank an unregged 200 bar BBMG might well be a possibility, in which case screw the detent

now I am going out to get totally f### ## cya

Amen brother, I'll be out within the hour

[POLAND_SPUD]

marbles suck!!!

I had a rather bloody accident today... one marble was slighly oversized so it didn't get loaded... instead it shattered upon firing and reminds of it left the ammo port and hurt my left hand which resulted in lots of blood everywhere

since I am an experienced spudder my first reaction was 'where the hell is my camera, I want to film it??'


marbles suck as ammo - their have poor BC, they are oversized and they they are dangerous.. don't use them

[jackssmirkingrevenge]

since I am an experienced spudder my first reaction was 'where the hell is my camera, I want to film it??'

Damage pics!



Marbles are indeed poor projectiles, I don't think hop-up would help when you don't have a consistent projectile diameter, it's the old golf ball in a drain pipe analogy - you never know in what direction it's going to leave the muzzle.

So smaller calibre, better ammo, n'est pas?

lol I have to quit drinking

If I had a euro every time I said that... well, I'd have a lot more money to spend on drink

[POLAND_SPUD]

today it looks more like some kind of a rash but it was bleeding quite intensively for about 15 minutes...

good for me the marble got totally pulverised and small fragments of glass didn't penetrate deep but if it hit me in the eyes instead that wouldn't be nice

lol that's a lesson learned - always use eye protection (as you can guess I didn't)


ohh one more thing about marbles - they ricochet a lot... see for yourself

target - 3/4" particle board
distance to the target - 15 meters
pressure 150 psi
as you can see accuracy has increased a little bit thanks to ghetto hop-up that I added



@JSR I included a close up of my hand at the end of it... sorry if it doesn't look like 'faces of death' now
[youtube][/youtube]

[jackssmirkingrevenge]

*much* better, it looks like it has a lot more cojones now but still, the fact that you can see the marbles in flight suggests that the velocity is fairly low, clearly you'll be much better off all round with a smaller denser projectile.

No blood but that looks like quite a bit of shrapnel you got there, it must have been pretty gory before you cleaned it up. And yes, always wear eye protection

[POLAND_SPUD]

the target - 3/4" particle board
the chamber is slighly larger (added a 3/4" nipple and a coupler to increase chamber volume)
pressure used - roughly 170-160 psi
distance to the target - 15 meters

at the end there is a slow-mo of the first part (1/2 of normal speed IIRC) so you can skip it if you want to



[youtube][/youtube]

as you can see I must have cut the chamber volume too much as even a slight increase in it results in noticeable performance increase... well, now I realize that 1" pipe would have been much better for chamber

yeah I know that it would be good to shoot something different or at least change the angle or move the cam...

but I really don't have more than 10 - 20 minutes each day to film it becasue there is always someone close to my range...
I'll have to find a new shooting range as it draws too much unwanted attention


any ideas how to build a hop-up inside a T added to the muzzle of the gun ??

[jackssmirkingrevenge]

Definitely an improvement, the marbles seem to have a lot more "oomph" now

any ideas how to build a hopper inside a T added to the muzzle of the gun ??

Eh? You want to load projectiles at the muzzle

[POLAND_SPUD]

lol I meant a hop-up.....

chamber volume must have been the problem...

It would be good for higher pressures but the spool valve is having some problems with higher pressures... it won't switch at all... well it might be a problem with the manual override only... I've got to do more tests

[POLAND_SPUD]

I converted my semi into a full auto gun with the use of rtx-41 timer (more details on it)

[youtube][/youtube]

distance to the target (the tree) ~15meters
pressure ~150 psi


I don't plan to improve it... it was done just to prove it's possible... and yeah I know I should have loaded more ammo

as I mentioned earlier I am going to convert this gun to 9.65mm calibre and make it a little bit more compact & ergonomic...
while I was testing it and filming it, the gun consumed so many marbles so fast that now I am sure that I am not going to add a full auto option to it


IMO full auto would need to use smaller calibre due to costs, ammo availability and other stuff like that... 6mm is probably the largest practical bore...

you might have noticed one of my post where I draw a diagram of a fully pneumatic full auto system... everything suggest that it could work and it wouldn't be more expensive than timer + solenoid valve combo...

[psycix]

Looking good there!
I suspect this to "nom" a gigantic air feed. What are you feeding air from?

[POLAND_SPUD]

fridge compressor + 9 L tank...

anyway, air in not a big deal... ammo is - I spent about half an hour sorting out oversized marbles just for a couple of bursts with this

[jackssmirkingrevenge]

Bofors Baby YEAH!!!!

I don't plan to improve it... it was done just to prove it's possible... and yeah I know I should have loaded more ammo

The only reason I do most things, and it's worth it

Nice one, would be nice to see a frangible target repeatedly perforated at very short intervals though

[dewey-1]

Poland Spud

That is down right very impressive!
I thought you might have success when you mentioned this idea some time ago.

Great job!

What size marbles fit the best? Actual diameter please.

[POLAND_SPUD]

I use copper pipe with an ID of 16mm... the marbles I buy are 16mm marbles... about two or three years ago they were of much higher quality and their size was consistent (about 15.5 - 16mm.... and only a few in a pack didn't fit... )

but now it happens very often that 75-90% of pack don't fit the barrel... if not sorted out carefully they cause stoppages

so if I have to buy 2 or 3 packs to get 100 marbels that can be used as ammo I think I might as well switch to ball bearings... the price will be the same

right now I've got about 1500 - 2000 oversized marbles all over my place... from time to time I use them as a buckshot ammo with a larger bore cannon

The only reason I do most things, and it's worth it

well I knew it will work but I wanted to inspire others and show that these timers can be quite useful