Shortening and recrowning barrel

[Joe Chicago]

Has anyone here shortened and re-crowned a barrel? Has anyone cold-blued exposed metal on a rifle? I am contemplating shortening my Weatherby Vanguard S2 barrel from 24" to 20" or 21". Ole Larry Potterfield from Midway USA makes it look so easy on his videos, but I am nervous that I will ruin an accurate rifle.

I hunt in Western PA where it is hilly and densely wooded, and almost all shots are under 100 yards. I am either in a stand or helping with a drive, so a more compact rifle would be ideal.

As always, thanks in advance for your help.

[603Country]

I'm pretty good with tools, but I wouldn't do the barrel shortening myself. There are plenty of guys on the forum that could and would do it, but not me. I'd find a good gunsmith. Surely that won't cost too much to have done.

But, maybe you could just cut off one inch and see how it goes. If it goes well, then go for the full reduction. Worst case, if you botch that first test cut, the rifle will be out of action only long enough to find the gunsmith.

[Joe Chicago]

I priced the tools to do the cut and the cost is three times what the gunsmith will charge. Since I do not foresee doing many of these operations, it does not make sense to make the investment in the tools.

Thanks for the feedback.

[edward5759]

Joe Chicago


If I can, I cut at 90 degrees to the bore. I like to use a TPG-320 in case if its chrome lined.
Other than that Go to brownells and get a 11 degree which is really a 79 degree Facing cutter and pilot.
When using the Facing cutter I like to place a lock ring around the cutter. This will stop any tool chatter at the end point.

[Bailey Boat]

It's easy with the correct tools. A file will bring the cut to almost square with the bore and then a facing cutter and pilot will finish the squaring process and then a crowning tool will have you shooting in no time......

[Nathan]

I think we would all be better off to have a gunsmith setup the barrel in a lathe so they can cut perfectly perpendicular to the lands. Then they can slice it off and recrown with a bit an cut a perfect recessed 11 deg crown.

This is like $50 to $75, I believe.

....or, I can buy hand tools which I can misalign to the bore, or have an original cut so far off that I struggle to cut the crow and have to buy something else. To some level, this method requires a perfectly square cut, which is impossible by hand. Out of square has the cutter bound only by the tightness of the pilot.

I think this method costs me $150 or so in tools??

[Roughedge]

Its easy if you have the right tools, A local smith should charge around 75 dollars and do it correctly. If you was closer I could do it for you.

[tet4]

Well, midwsyusa, has a video on cutting a barrel with hand tools. I'd try it. It looks easier than dovetailing a drawer with chisels.

[mikikanazawa]

I have crowned many barrels for gunsmiths over the years as a contract machinist. In my opinion, to do it correctly takes a lathe that's setup for barrel work, and a truly knowledgeable operator.

Having said that, I have seen very serviceable crowns done by hand with piloted cutters. They do require meticulous work habits though, and prefereably a constant flow of cutting fluid through the bore to instantly clear the chips. (If chips are not constantly flushed they will work themselves between the pilot and bore and scratch the lands.)

Cold blue is very suitable for finishing the newly cut muzzle, and if applied properly, should last the life of a rifle that receives nominal care.

The way I CUT the barrel is with a band saw, leaving the barrel approximately .1" longer than the desired finished length. It's a rough cut, and not square, but very fast. I used to part them off in the lathe but it took a long time and if the parting tool jammed, the barrel could be severely marred.

The way I CROWN the barrel is in my lathe, using barrel-specific tooling. I square the crown to the last six inches of bore, ignoring the chamber. Every barrel I've worked on has had a bore that was "jump rope" shaped -- if the chamber end and muzzle end are set concentric to the lathe spindle, the center of the bore length will have significant runout.

Squaring the crown in this way requires a range rod and very precisely-fitted bushings. I use a pair of 0.0001" test indicators and it takes about 90 minutes to set up the barrel in this way.

The actual cutting of the crown only takes a minute, plus another 10-15 to double check the work (e.g., barrel may have shifted during the cut). If the customer wants the muzzle threaded I do it at this time, and then later use a piece of the cut-off to make a thread protector.

To BLUE the now-exposed metal I wash with soap and water (to clear the oil and any remaining chips), degrease the portion to be blued, and mask the rest. I have gotten better results by heating the metal with a heat gun before applying the blue. It goes on darker with more even coverage, but I can't say it's more durable. The masking is to prevent the cold blue from getting on the original blue, because it causes the original blue to discolor or dull.

The instant the cold blue is applied I remove the masking and wash again in hot soapy water to deactivate the cold blue. This is an important step! Cold blue is very acidic.

Then I'll "kiss" the bore with a 60-degree countersink to remove that last tiny burr. This removes a bit of the cold-blued area and leaves a tiny silver ring. This is my final check to ensure a quality job, and a way for the customer to verify it too. If the muzzle is even slightly out of square with the crown, the ring will not be perfect.

In my experience, shot precision is much better with shorter barrels, so as long as the crowning job is meticulous you shouldn't be losing anything except some muzzle velocity.

ETA: On the $75 price estimates -- I live in the Los Angeles area so I have to charge more... you know... cost of living!

[guncrank]

Sure plenty

Use of lathe is best
Hand powered barrel crowning tools are nice to use and have but
For one barrel not worth it.

You can cut/crown a barrel with a hacksaw and square the end with a file and lap the crown with a brass screw.

It does not matter the method as long as the crown is ninety degrees and concerntric to the bore.

[603Country]

mikikanazawa, that was an extremely interesting post. Thanks for sharing your knowledge and experience.