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REAMERS Rougher vs Finisher

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03 July 2005, 14:15
morton3
REAMERS Rougher vs Finisher
Can anyone tell me the difference between a rougher & a finisher reamer ?

Is it as simple as the names suggest, whereby a gunsmith uses the rougher to remove most of the metal for the chamber & then takes a light cut with the finisher to complete the job ?

I am a Fitter/Machinist by trade & understand the principles of machining etc. Is there a website or a book anybody could suggest that explains speeds for reaming & how to do it, methods used for measuring headspace etc & basically how to build a rifle.

Simply put, I really want to learn how it is all done, Chambering, threading for correct headspace etc.

My local Gunsmith of 10yrs or so has left the industry, so I need to do the work myself Smiler

Thanks in advance
Morton


If it sounds too good to be true, It usually is !
03 July 2005, 14:45
afro408
Morton,
Welcome to the wonderful world of Gunsmihing. Get onto http://www.bundukibooks.com and get a copy of Roy F Dunlap's book on Gunsmithing. It is a classic and will have all the info you want.
You did understand correctly, the Roughing reamer is used to get out the majority of the chamber and the finisher is just that.
You can contact me online at ajs408@bigpond.net.au
Cheers
Tony
03 July 2005, 19:55
butchlambert
Morton, I think that you would be better off boring just shy of your finish dimension and then using your finish reamer. Just talked to my mate Stuart Elliot this morning. Said it is cold in Canberra. Butch
03 July 2005, 20:30
Rick 0311
You want to keep a finish reamer as sharp and unworn as possible so you get smooth, accurately sized chambers...and it ain’t gonna stay sharp and unworn if you are trying to hog-out too much material with it. Reamers are designed to “slightly†enlarge and shape existing holes, they are not boring tools meant to remove lots of material.

A hole bored in steel with any cutting tool is going to be more accurate/straight/smooth if it is “worked-up†to rather than trying to bore it to finished size in one pass.
03 July 2005, 22:03
Cheechako
Morton

Instead of getting a rougher and a finisher, get a re-size and a finisher. The re-size can be used as a rougher and then can be used to make sizing dies. A re-size is usually about -.002 plus or minus in all dimensions. A rougher can be used for only one thing. Do as Butch suggested though, bore out as much as you can before using any reamer. That makes it a lot easier and, usually, a lot straighter.

Ray


Arizona Mountains
05 July 2005, 17:09
Gadge
Dunlap's book is good for all-round gunsmithing, but you may be more interested in Hinnant's "The Complete Illustrated Guide to Precision Rifle Barrel Fitting", which I've seen recommended here.

Cat No. 404-100-000 from Brownell's - you'll be wanting their catalogue anyway!