Need Help!- .22 LR Rifling cutter or broach.

[Rodrigo]

Dear Sirs

I have spent many hours searching the internet for information on rifling single point hook cutters or broaches, but besides some articles on barrel making and rifling, I found nothing about the cutters or broaches geometries for rifling a .22 LR barrel.

Can any one post here photographs or drawings of a single point hook cutter or broach ?

Even a hand made drawing ( preferably with some dimensions ) will be very useful !

If you know about sites that have information about this subject please share the links with me.

I found information about ram mounted cutter boxes for single point hook cutters, but they are to be used for larger bore barrels, I think that for a .22 LR barrel with such a narrow bore the machining procedure is different.

Thank You Very Much for Your Help.

[MrWild]

Saw a movie about Kentucky long rifle production the old way. The machine was two and a half times longer than the barrel. The barrel broach is keyed to a screw shaped cam longer than the length of the barrel. Only one rifling is done at a time. The broach itself is just as long stiff rod that has a groove at the tip for a HSS cutter. The cutter was reset for cut depth after every pull through. After each rifling is cut, the broach is twisted a bit and remounted for the next groove. Slow and tedious, that's the way it was done.

[jerryjoeed]

Get a copy of "Modern Gunsmith" by James Howe. It has excellent descriptions of how to machine and fit a rifling head as well as dimensioned drawings for .22 and .30 cal. heads. The book is from the '40s so, for example, the information about reaming and burnishing is out of date. But, there is so much good information that the book is a must read. You just have to understand that manufacturing and firearms technology have changed much since the book was produced.

[Rodrigo]

Dear MrWild

Thank you for replying.

During the search for rifling cutters I have found a lot information about rifling machines ( old and modern ).

At the web we can find designs of rifling machines to build at home, unfortunately there is scarce information about the rifling cutters / broaches.

If you came across something like that please let me know.

Best regards.

[Rodrigo]

Dear Mr JerryJoeed

Thank you for replying.

Very nice direction you pointed me to !

I have heard before about rifling heads for hook rifling cutters but I thought they were used only to put rifling in the large bores of larger caliber rifles / handguns.

I followed your suggestion and had a look at Mr. James Howe book.

Now... to make such a tool for a .22 LR barrel... It's not easy task !

For a " not much " experienced machinist like me, it almost looks like watchmaker precision machining !

I didn't understood very well the drawing and dimensioning of the described .22 LR " hook " cutter, the scanned page of the book is too blurred.

I am attaching a drawing in JPEG format with this post, can you tell me if it is correct ?

Do you know the correct dimensions / geometry of the hook cutter ?