scratch rifling

[isobar]

hello,does anyone have any experience of scratch rifling?i have a smooth bore diana 27 and although the trigger is excellent the rifle is not as accurate as i would like.is scratch riling worth having a go at?can it be done at home by an amateur?the other alternative is to source a rifled barrel but that seems unlikely or expensive.

thanks for looking

[Faerie]

According to Cardew & Cardew in "The airgun from trigger to target" scratch (or microgroove) rifling works perfectly well.

Apparently, an early 20th century firearms expert named Dr F.W. Mann demonstrated "that if a lead plug covered with emery was spiralled backwards & forwards along a smooth bored barrel, the bullets would pick up perfectly on the shallow scratches. They would then leave the muzzle, spinning just as though the barrel had been rifled in a more conventional manner."

The secret here, I imagine, is to make the lead plug spiral at an even rate along the length of the barrel so that the "rifling" imparted does not vary in pitch.

[Neil54]

What caliber?
You can get rifleing buttons in .22.
It may be possible to make one in .177

[isobar]

thanks for the replies,it's a .177 barrel,i have no tools as such only ideas and i like to have a go at things if there is a reasonable chance of success.i quite like the idea of scratch rifling because it sounds more accessible and less precise to me.don't laugh but could i have fibreglass rod with coarse emery glued to it and turning on a battery drill and feed the barrel on to it? at the minute the bore is like a mirror.

[lew07]

I would think a ground drill bit would be the way to go.

[crowbar]

Spinning a drill will just cause rings,you need a slow helix 1 in 16" is common ,you could do it by hand pushing a glass rod
with emery glued to it along the barrel whilst feeding the barrel with the other hand and rotating it,but I wouldn't bother I
would recrown the barrel and find a suitable pellet

[isobar]

I would think a ground drill bit would be the way to go.

that's certainly food for thought,not sure how i could feed it through the bore?

[Faerie]

that's certainly food for thought,not sure how i could feed it through the bore?

At this moment I'm not exactly sure how to do it, but it occurs to me that it may be possible to use another (rifled) barrel, along with something that will engage with its rifling and a sub-calibre rod to connect with whatever carries the emery if the barrels are placed end to end, then push this assembly down the rifled barrel toward the smooth bored barrel so that it imparts a "spin".
Does this make any sense to you or am I talking through my hat ?

[crowbar]

I think you would have to pull it through the barrel.

[Shed tuner]

yeah, you need something that will uniformly spin and feed at the same time, as stated above.

a square section (say 1/4") length of steel, heated and twisted (one turn in 16" is common), might form a suitable pattern ? feed it though a square hole, and the rod will twist as it feeds. youd obviously need to attach a sub .177 sized steel rod to the end of it, and the end of that would need your "scratch filing mandrel" or button, or whatever it's called.

Just thinking aloud... something like a giant yankee screwdriver

and yes, definitely pull, not push...

[Shed tuner]

just found this

[Neil54]

Buttons are pushed, usually with a hydraulic press.
The button controls the twist.

[acmsarh]

£15.95 on aliexpress 4.5mm
https://www.aliexpress.com/item/4000...d=4ATgIGgcxcXV

[Shed tuner]

Buttons are pushed, usually with a hydraulic press.
The button controls the twist.

yeah, but if we are talking scratch rifling... I'd doubt the depth of scratch would be enough to provide the rotation ?

[Shed tuner]

£15.95 on aliexpress 4.5mm
https://www.aliexpress.com/item/4000...d=4ATgIGgcxcXV

those are going to need serious force to push through...