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View Full Version : Fred wants to know rifling question



Alistair Hosie
12-19-2006, 12:27 PM
HI my old pal Fred asked me to ask you is barrel rifling done with a broach?Alistair

rws
12-19-2006, 12:43 PM
The three most common types of rifling are, hammer forged, button and cut. Cut rifling is done one groove at a time, for each groove. Button is either pulled or pushed, one pass does it. Hammer forged, well that's factory stuff.

I believe there was some "broaching", where the whole barrel was rifled at the same time, similar to cut rifling in that it progressively cuts deeper, but I don't know who does it.

I use benchrest grade barrels only, and those are either cut or buttoned.

thistle
12-19-2006, 12:57 PM
There was quite abit written about the subject on the PM forum a while back, try the gunsmithing forum, there was even pictures of a homemade rifling machine.
I hope you and fred are not planning on building a Improvised Haggis Launcher to lob haggi over the border towards John Stevenson.
Her MajestiesGoverment has decreed that stuff with rifling in it is naughty and can hurt things and make holes in peoples roofs.

JCHannum
12-19-2006, 01:53 PM
This site has a very good description of the various methods of barrel making and rifling;

http://www.border-barrels.com/articles/bmart.htm

Cut rifling can also be considered as being broached, and the cutter is called a broach by some. It typically is pulled through the barrel in multiple passes, and cuts one groove at a time.

Rusty Marlin
12-19-2006, 02:40 PM
I know of two companies that broach pistol and handgun barrels.
The two different broaching machines I have set up either hold the barrel still and rotate broaches as they are pulled or pull the broaches straight as the barrels are rotated. Both machines are pulling two broaches. The first broach makes the gun drilled hole round and to bore size ( it also aligns the machining marks to the direction of the bullet path) . The second broach cuts the rifleling grooves.
The cutters are about 3ft long and have around 24 teeth with .0005-.0008 steps in diameter between teeth.

gzig5
12-20-2006, 05:05 PM
There is one company specializing in broach cut barrels for AR15 rifles, but the name escapes me at the moment.