Rapid barrel specs

[risingphoenix]

Hello,

I currently have a Rapid MK2 FAC with 19" barrel (.22).

Having an unused 23" .22 Lothar Walther barrel blank here, I just wanted to turn it down so to fit the Rapid action.

Could somebody please tell me the exact dimensions I have to use? Maybe even a small drawing?
Looking to confirm my measurements made on my barrel (so surely not exact).

Thank you very much
Pierre

[Andy.I]

Pierre

You won't go wrong if you just duplicate the dimensions of your current barrel.

One tip: if you want to black your barrel then you need a decent finish. You need to first turn it down between centres using a steady. Then centreless grind it to size and then polish it. Don't be tempted just to centreless grind it because barrels are invariably not concentric, and if your breech is out then you may well get puffing.

Another tip: when you drill the small blind hiole for the barrel locating grub screw which goes through the forward scope mounting hole, use an endmill so you get a flat bottomed hole. This makes is easier to adjust and there will be no tendency for the tapered point on the grub screw to centre in the hole, thus pulling the barrel out of position.

HTH
Andy

[Shed tuner]

IT WOULD BE EASIEST IF YOU ONLY TURN IT DOWN WHERE IT NEEDS TO FIT INTO THE ACTION - 15.8 MM OD IIRC

(caps off, can't be arsed to retype )

HTH - JB

[Sid]

Hi Pierre ( I WILL answer your mail today )
My micrometer says 15.71mm for the barrel....

[Andy.I]

Originally posted by BuddyBoy
IT WOULD BE EASIEST IF YOU ONLY TURN IT DOWN WHERE IT NEEDS TO FIT INTO THE ACTION - 15.8 MM OD IIRC

But it's still a good idea to turn it between centres unless you are certain it's concentric!

Andy

[Sid]

You don't have to work between centres if you have a lever action dial gauge and a 4 jaw chuck ( and the blank fits through the lathe spindle ).
You set the blank in the 4 jaw so it's true to the bore rather than the O\D using the lever action dial gauge mounted in the tailstock.

This neccessary for owners of smaller lathes who can't get 23" between centres.

[Shed tuner]

Originally posted by Andy I
But it's still a good idea to turn it between centres unless you are certain it's concentric!

Andy

Agreed - just can't see the point in reducing the OD of the whole thing

On another point, are you sure you can handle the extra weight at the front ? Try handing a few inches of iron bar on the front and see how it fells - just for a couple of extra FP ?

[Sid]

PS - Andy, can you give me a bell ?

[risingphoenix]

Thank you all for your quick help!

As I'm using a small lathe I use Sid's method of putting it in a 4Jaw chuck and center it. Has worked for me until now.

And the extra few inches really don't weight that much. I had the pleasure of handling a Rapid Mk2 .25 (as you know, they use 23" barrels), and IMHO it feels better.

BTW I measured 15,72 so you all know

Best regards,
Pierre

[Andy.I]

Pierre

YHM ref CF silencers.

Andy

[Sam]

Theo barrels are usually around 15.78mm o.d, (tolerence on these seems to be around +/- .05mm), the reciever is exactly 16mm, so anything in that range that will provide a nice pushfit will suffice, the closer the better though as the action to barrel transfare is a metal to metal seal.

Best to just turn it down at the breech to a length of 41mm to acomodate the recievers depth, then again at the muzzle to accept the silencer.

The step at the breech for magazine location should be 10mm o.d x 1mm deep, you can copy the blind location hole and transfare port off the other barrel, as its FAC i'm not giveing the dimensions on here.


HTH.

[risingphoenix]

Thanks SBSD, very useful informations here.

Andy, got mail and will reply, but want to propose some different lenghts than 800mm (something around 500, 550 and 650 for 16, 19 and 23" barrels. And perhaps 300mm lenghts for conventional silencers).

Pierre