Best way to Cut a Barrel down, if you had these tools available...

[1377x]

umm
like i said before let me know if you can find one i can buy
you might want to try adding to your cart then tell me if it says the same thing it tells me

[YSYEO]

This is not a dovetail fixture, but it will serve for the barrel filing under discussion.
Completely hardened and ground tool steel.


http://www.huronindustrial.com/mm5/merchant.mvc?Screen=PROD&Store_Code=his&Product_Code=1-814-110&Category_Code=

If you want to comparison shop, google "hardened v-block".

[0351_Vet]

umm
like i said before let me know if you can find one i can buy
you might want to try adding to your cart then tell me if it says the same thing it tells me

@1377x

Yeah, that's a bummer. I even pulled the trigger on it and then talk to the staff. no longer Available. 

[sbcrockett]

sorry to go a little off-topic, but thanks for your new avatar, Ed. I'd forgotten I saw that before and I laughed just as hard now as I did then!

[0351_Vet]

Target Crown



Picture shows a 'step' type target crown on a Green Mountain .22 caliber barrel.


Below is a description and procedure for making a step type target crown taught me by Ray Dixon, who cuts target crowns on target and varmint rifle barrels as part of his profession.


Using a lathe with steady rest and cutting tool to turn and cut the work piece, the muzzle is squared then stepped in a few hundredths of an inch. The sharp edge of the muzzle is turned off at a non-critical angle to help protect it from dings. Leaving metal above the circumference of the step (the crown) protects the crown from dings.

The step is angled down at about 45 degrees to help direct gas turbulence away from the exiting bullet.

Because gases should escape with equal resistance across the entire area of the crown, it is important that all crown surfaces be smooth and similar throughout its area. Attention to this becomes more critical as the crown approaches the bore.

Using a 60 degree piloted bit attached to the tail stock of the lathe, the sharp 90 degree edge of the bore exit is turned off at a 60 degree angle. The importance of this is to protect the bore edge from gas erosion and thereby ensure the bore exit remain smooth with no irregularities along its circumference. Great care is taken to make this cut very smooth so that it be alike along its entire surface. To aid in this the barrel is turned only by hand while making very slow advances of the tail stock, which contains the piloted bit. To help ensure the 60 degree edge be consistent in depth and bit chatter minimized this cut is kept very shallow, only about 0.020 to 0.025 inch in depth. The pilot of the bit is a diameter which matches that of the bore closely enough to keep the axis of the bit aligned with that of the bore, keeping bit chatter down and depth consistent.

Should the bore exit not be consistent about its perimeter gases escaping unevenly around the bullet base will cause bullet yaw and loss of precision.


    11 Degree Target Crown


Below is detailed the tool and procedure recently used to apply an 11 degree target crown to the muzzle of a Ruger model Number 1B, caliber Springfield 30-06.



Left - .308 caliber brass pilot, 79 degree muzzle crowning cutter, cutter handle and allen wrench for tightening pilot to cutter.
Center - the assembled tool used for cutting the 11 degree target crown.
Right - the business end of the tool.

All parts of tool were purchased from Brownells . The hex wrench did not come with the tool.
The 79 degree cutter is found through their web site index under 'CROWNING/BARREL' or 'CHAMFERING/BARREL'.
The handle for cutter and the pilot are both found under 'CHAMFERING/MUZZLE'.
Pilots are advertised for most calibers and are available in steel or brass. Brass was chosen because it is softer than the rifling lands.
Two sizes of cutter are advertised: 1/2 inch diameter and 3/4 inch diameter for small and larger barrel diameters. The cutter used here is the 3/4 inch version which works for small and larger diameter barrels. Note that using this cutter, crowning a 1 inch diameter barrel would leave a minimum of 1/8 inch radius uncut but none-the-less would yield a proper functioning 11 degree target crown.


L - crowning cutter with pilot inside bore, ready to start cutting.

Center - beginning of target crown after only 10 or 12 light 1/2 rotations of cutter. Care is taken to keep light and consistent downward hand pressure centered on bore so pilot does not wobble. Cutting is performed slowly and can be stopped and resumed at will but it is important to keep cutting surfaces coated with the oil and to clean metal shavings from bore, muzzle and cutter before re-inserting pilot.

Right - to keep shavings from getting between cutter face and muzzle care is taken cutter never leaves the surface of muzzle while cutting is being performed. Cutting is often stopped to clean shavings from muzzle, bore and tool and to check depth of cut.As cutting goes deeper into muzzle cutting slows because more muzzle face is contacting cutter surface. Cutting is often stopped to check for depth and to clean away shavings. The muzzle becomes very sharp where it enters the bore and ruff cutting is stopped just short of maximum barrel radius. Shown above the ruff muzzle is ready for finish cutting after about eight careful cutting sessions.




Left - finish cutting is performed with increasingly lighter pressure as cutting progresses until almost only the weight of tool is applied to the muzzle.
Center - crown after finish cutting.
Right - a thin and even amount of 00 steel wool is placed on cutter face and used to lightly burnish any microscopic burrs off muzzle crown. Care is taken to flatten the wool against the cutter face before inserting pilot into bore and it is important not to over burnish using this method because any steel fibers accidentally allowed into bore could score rifling lands.




Left - after using alcohol to degrease the muzzle OXPHO-BLUE from Brownells is used to cold blue the muzzle.
Right - Three coats of blueing agent was applied to muzzle. After each application the muzzle was wiped with dry towel and lightly polished using 0000 steel wool.

[1377x]

sorry to go a little off-topic, but thanks for your new avatar, Ed. I'd forgotten I saw that before and I laughed just as hard now as I did then!

there is a 1377x avatar thread going now as we speak

@1377x

Yeah, that's a bummer. I even pulled the trigger on it and then talk to the staff. no longer Available. 

i know been trying to get something like that for a long time.tired of spending money on getting barrels cut and crowned.i mean i could have bought a lathe from just the money i spent on services not including the barrel.
  now that link ysyeo posted is worth looking into

[1377x]

ysyeo
thanks for the link!
just what i am looking for and they accept paypal!

[0351_Vet]

We need to get one of these....

[1377x]

what is that/

[breakfastchef]

We need to get one of these....

Bet you could make a few bucks everytime you go to the range with that tool.

[1377x]

ok so its a crowning tool
to get a price and availability contact owner
heres the video of the tool in use
[youtube]https://www.youtube.com/watch?v=-Xpzv1Spsnk#]Precision Muzzle Crowning by Dave Manson[/url]

[RC1947]

BERT, that's an excellent, and simple way to assure an accurate cut.  Thanks! RC

[arkmaker †]

Man, that is an excellent crowning tool! What's the cost? Around 500 from the looks of the video....Steep for us airgunner, but I don't think a gunsmith should be without it. Easier than a lathe!

[1377x]

at the end of the video it says $300-$400 depending on the pieces you get
thats about 30 barrels to break even 40 to make a profit
thats with airguns.firearms will get a higher charge for a recrown
it costs me around $15 to get a barrel cut and crowned.i have gone through more than 40 barrels.not all for myself.i have sent out a lot of barrels to people who couldnt get them usually when crosman is out and i can still get them.