"In the world of spuds today"

[Gippeto]

Very nice. 8)

Bought myself a little something as well.

Converted to .25 cal about 15 minutes after it arrived.

I think I need a new red dot too.

[jackssmirkingrevenge]

Not bad for a 160€ gun I think, shooting 10 mm groups at 10 meter now, if I was a better shooter it'd be hole in hole

Nice, bet there are machined mods on the horizon

Bought myself a little something as well.

mmmm... this one? http://www.airgunsofarizona.com/blog/20 ... lecto.html

Pretty!

Crying out for a nice suppressor What slug weight and how fast in 0.25"?

[Labtecpower]

Nice, bet there are machined mods on the horizon

Yep, I want a handle like the one I made for Jake, and I certainly want to give the gas ram a try, spring twang sound cheapy hehe

First change on the gun has been made;



Found this ring behind the seal between the barrel and piston chamber, has a 2mm hole in it, so it chokes the flow tremendously.. and if I find something I don't like it gets pulled out
Next to it is a JSB exact 4.52 for comparison

[jackssmirkingrevenge]

Careful, the black art that is mastery of the springer airgun implies that a bigger transfer port does not necessary mean more power.

[Labtecpower]

I can't see the logic behind this black art...
The groups have gotten smaller since I took out this ring, it seems to have less vibrations..

Maybe i'll just put it back in for more testing

[jrrdw]

Experiment with port sizes. Make several copies with different size ports...mite be fun.

[Gippeto]

Transfer port size in a springer can have a major effect on compression heating...hot gases flow faster...yes? Too little compression will also have the piston slamming into the end of the cylinder...not so good.

Jack... No suppressors here...suppressor= prohibited device = jail time.

A trade off I'm willing to make for an easily available firearms license (PAL).

Alecto...yes.

After "tweaking" the pressure relief valve, JSB Kings (25.4grain) @ 450 fps...20.5's would likely be getting ~470fps or so, which is getting close to the legal limit here which separates an "air pistol" from a "pistol"...which requires a license I don't have (RPAL) and adds restrictions to storage/transport/usage that take most of the fun out of an air pistol.

Should be plenty of snap for spring time "whack a mole".

[jackssmirkingrevenge]

Transfer port size in a springer can have a major effect on compression heating...hot gases flow faster...yes? Too little compression will also have the piston slamming into the end of the cylinder...not so good.

That's the gist of it, not something I would play with that much.

Jack... No suppressors here...suppressor= prohibited device = jail time.

I know, just putting it as a hypothetical. I bet it's not too loud in any case though

After "tweaking" the pressure relief valve

I read that as "jamming in place"

JSB Kings (25.4grain) @ 450 fps...20.5's would likely be getting ~470fps or so, which is getting close to the legal limit here which separates an "air pistol" from a "pistol"...which requires a license I don't have (RPAL) and adds restrictions to storage/transport/usage that take most of the fun out of an air pistol.

Very decent for an air pistol, that's just under the legal limit for air rifles in the UK!

Reminds me of the Quackenbush efforts: http://www.quackenbushairguns.com/shot_pistol.html

[Labtecpower]

That's the gist of it, not something I would play with that much.

popped it back in place, needs more research before I make any changes
I still think it's too small, a lot of other guns have a hole about a mm bigger..

[jackssmirkingrevenge]

I still think it's too small, a lot of other guns have a hole about a mm bigger..

... but they have different piston diameters and strokes, spring strengths etc.

As jrrdw suggested:

Experiment with port sizes. Make several copies with different size ports...mite be fun.

Grab a chrony and do some science!



Random footnote, wyz - come come you never mentioned this?

[Labtecpower]

... but they have different piston diameters and strokes, spring strengths etc.

As jrrdw suggested:

True, I shouldn't apply the figures of other guns to mine

Grab a chrony and do some science!

I hope I can find someone near me who has one, I don't have the money to buy a chrony for testing purposes

[jackssmirkingrevenge]

I hope I can find someone near me who has one, I don't have the money to buy a chrony for testing purposes

Could be something a bit more rudimentary since you're mainly interested in relative data as opposed to actual fps values. For example water filled beer cans in a row, count how many each variation penetrates.

[jrrdw]

but they have different piston diameters and strokes, spring strengths etc.

Don't let that stop you, so much as .05mm might make a outstanding differance. You never know, if you have the means and time etc...

[Labtecpower]

I'm going to take a look at work tomorrow, if i'm lucky they have very thin 14 mm rings somewhere

I have very little time on my hands, but that isn't enough to stop me from having fun hehe

1000!!

[jackssmirkingrevenge]

I'm going to take a look at work tomorrow, if i'm lucky they have very thin 14 mm rings somewhere

... and plenty of empty beer cans

1000!!

pfffft...