lapping tool for barrel crown

[p5200]

http://www.midwayusa.com/eproductpage.exe/showproduct?saleitemid=718110&t=11082005

is this the right tool for a Savage 10FLP .223 with its target crown? also, has anyone ever used one of these with good success? I would have a gunsmith do it If I had one that could. we have only one, and he says he is not equiped lol!   

[trotterlg]

I would say that tool is intended for a standard rounded crown.  A target crown is usually a strait cone taper at 11 degrees very (shallow taper) like this: http://www.midwayusa.com/eproductpage.exe/showproduct?saleitemid=665761&t=11082005 Larry

[gunnut69]

The crown is cut from the outside of a barrel to the bore. This leaves a sharp edge and the lapping tool is made to slightly break the edge(champfer) the edge of the bore... the crowning tool cuts the entire crown...

[trotterlg]

When I do a crown on a barrel I cut from the bore to the outside just to eleminate the burr in the bore.  First I put a center in the bore and turn the outside of the muzzel round  related to the bore, then I put a steady rest on the trued muzzel and cut the crown, starting from the bore to the outside of the barrel, this leaves the crown exactly square with the bore and not off center any.  I cannot think of any other method that would result in a more accurate crown.  The cutter with a bore guide would probably be second best and is the tool to use if the barrel is already mounted to the action.  Lapping the crown by hand will clean it up and probably be better than nothing, but there is no way that it will result in a perfect crown. This is a picture of how I do mine, this is after the last pass of the cutter, note there is no burr at all inside the bore, now I just touch it with some emery cloth and it is good to go.   Larry

http://www.22-250.com/shoot8.jpg

[gunnut69]

I've used both the lathe and a piloted cutter to cut crowns and find them equal.. Perhaps there is a mionor difference but it would truly be minor.. If the pilot fits well and the cutter is used carefully, as should be the lathe, they both cut wonderfully accurate crowns.. Thumb polishing the spinning crown would be the job the lapping tool would accomplish.. the thumb works just fine!  Again,, I've used both,., The standard rounded crown I used to cut with the lathe as I've not found a good cutter for the piloted device to accomplish that cut.. maybe that's the reason for the existance of the 'target' crown.. The rounded crown cutters are specially ground to the shape of the crown to be cut and are sometimes less than perfect..