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General Discussion To Gateway To Airguns => The Shop => : haertig September 18, 2009, 07:08:11 AM

: Machinest question: enlarging hole diameter
: haertig September 18, 2009, 07:08:11 AM
I have a barrel weight with fire sight from a Daisy rifle that I'd like to install on my Gamo if possible.  I am not sure what tool a machinest would use to do what I need, of if it's worth the effort.

The barrel weight is 3.5" long, 0.85" o.d., 0.475" i.d. (measurements approximate).  It is heavy, so I think it is probably steel and not aluminum.  But I'm not sure.

What tool/effort/cost would it take to bore out the i.d. to 0.6"?  Boring to a depth of 2.5" would be good enough (that makes it past the set screws it uses for attachment).

The Gamo currently uses a plastic front sight piece that will continue working, but the Daisy part is much nicer and has a much better fire sight, plus it's the correct height for the rear sight I want to use.  It is a spare part I have now after replacing my Daisy's front sight with a tunnel sight, so I was thinking I could "convert" it (more likely, "have it converted by someone with the proper tools/knowledge").  But it wouldn't be worth it if this would be a costly operation to have done professionally, or if I can't find a friend with the proper tools to do it for free.

Thanks!
: RE: Machinest question: enlarging hole diameter
: kiwi September 18, 2009, 10:29:09 AM
Hi....
Really its needs to go in a lathe then rebored with a
reamer...a drill or slot drill would do the job ..
but if yer don't have access to a lathe....
get a length of tube thats a very lose fit in the brake
& hacksaw a  slot in one end about 40mm long...
chuck it in a drill press rotate the table out of the way..
slide a short length of emary tape "sand paper type stuff"
in the slot "cut" rap it around the tube...slide the brake over it & rotate
it in the brake..will slowly sand out the bore as you slide
the brake up & down...change paper often ..

OR buy a hand reamer the right dia...

Pete

: RE: Machinest question: enlarging hole diameter
: haertig September 21, 2009, 06:40:56 AM
Thanks for the reply.  I had a very generous offer from a new friend who volunteered to fix up the barrel weight for me in their machine shop.