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Newtosavage
02-21-2022, 05:04 PM
I'm curious how many of you cut and recrown your own barrels at home.

I've been doing this for about 6 years now and darned if every barrel I've chopped and recrowned by hand didn't shoot better afterwards. Not sure if it's a better crown than the factory crown, or the shorter barrel is just stiffer. Either way, I quit worrying about it years ago.

All my barrels are lightweight hunters in the 20-21" range. That's just where they balance the best for me I guess.

I followed the method described by Larry Potterfield for cutting and recrowning a barrel, and finish with a brass screw and valve grinding compound followed by abrasive toothpaste and 1000 grit wet/dry sandpaper. They come out looking and shooting great.

https://www.youtube.com/watch?v=b43odFm0mrI

Here are the results from my latest barrel, after chopping my .284 Win X-Caliber down to 21" and recrowning

Phreddie30.06
02-21-2022, 05:18 PM
All I am capable of is cleaning guns after my wife gets them dirty. Ask her! That looks like it works out pretty good for you.

Sent from my SM-G991U using Tapatalk

Underdog
02-21-2022, 06:13 PM
Very nice work you've done there, and I have several rifles I'd like to shorten a bit. I never really gave it a try though, but I believe it is something I could accomplish once I got past the first cut. I have an old Axis with a damaged trigger and sear that is unable to fire anymore, I guess that would be the perfect practice rifle to hone my skills on.

Newtosavage
02-21-2022, 06:17 PM
Here's one I did recently on a .308 Savage barrel. Prolly shoulda kept that barrel.

84428443

Newtosavage
02-21-2022, 06:19 PM
The key is the use a clean, new brass flat head screw and some good valve grinding compound like this

8444

PhilC
02-21-2022, 06:28 PM
Can't argue with successful results. Nice work!

NF1E
02-21-2022, 06:51 PM
Been using a Manson crowning kit for years. Brought some real dogs back into the fold.

charlie b
02-21-2022, 07:06 PM
Yep. As long as the cut is square it is a pretty simple job. I like to 'crown' them as little as possible. Since I don't take them to the field I don't have to worry about nicking the muzzle.

Dave Hoback
02-21-2022, 07:21 PM
I’m actually machining a piloted crowning tool. My son put another AR pistol together & chopped a barrel he had. So now Dad has to fix it, LOL!

I was just gonna do what I used to with AKs I built in ‘05, but decided machining a piloted 11 degree crowning tool would be fun.

pdshooter2
02-21-2022, 08:40 PM
the key is the use a clean, new brass flat head screw and some good valve grinding compound like this

8444

flat head screw ??

Blue Avenger
02-21-2022, 09:17 PM
I always thought it was a Brass, straight slot, Round head screw recommended
.

Dave Hoback
02-21-2022, 09:28 PM
Yes, it’s Round head brass bolts. Brass Carriage bolts work great as they have no slot. Just a perfect round head.

Newtosavage
02-21-2022, 09:51 PM
I always thought it was a Brass, straight slot, Round head screw recommended
.

Yes, that's what I meant.

Fuj'
02-22-2022, 06:54 AM
I indicate the bore in my lathe and cut. Most are 11 degree.

Sometimes when you think your barrel is going south, a re- crown
can bring it back for a few hundred rounds. I will cut 1/2" off the
barrel first.

Dave Hoback
02-22-2022, 07:55 AM
Yup’er.. that’s the way to do it. Unfortunately, I no longer have use of a lathe, and no room for a proper unit. But those who do, that’s the right way!


BTW: Just a little piece of info.. Anyone know where 11 degrees came from? You can’t find the answer. No one knows. It was just seemingly “chosen from a hat”, and it caught on. Truth is, you could cut it at 12, 13, probably 15 or 20 degrees & not see a discernible difference. Just taught that was interesting. 11 wasn’t chosen based on scientific testing with modern machinery. Someone just decided on it.

Blue Avenger
02-22-2022, 09:12 AM
11 degrees was picked as that was supposed to be the angle that gas exited the bore when the bullet cleared the bore.

bsekf
02-22-2022, 01:20 PM
OK, so you use a brass carriage bolt chucked in a drill press with the barrel held perpendicular. Liberal application of valve grinding compound. Seems like the brass bolt head would form to the muzzle/bore rather than the muzzle/bore forming to the bolt head? Why not use a carbide deburring tool rather than a brass carriage bolt? I agree the angle of the muzzle is not as important as being square and sure wouldn't want anything turning in the bore to screw up the last few inches of the rifling.

We agree that it is impossible to bore and rifle a barrel perfectly straight (tools drift), so I figure by cutting it, removes some of the drift. Virgil King (Houston warehouse) said 21.75 is optimum barrel length.

Bill

Newtosavage
02-22-2022, 02:08 PM
Chucked in a hand-held drill and you rotate the drill itself as you form the crown. This keeps the brass from forming to the bore and gives you a nice uniform crown. The valve grinding paste does the work.

I also don't want anything turning inside the bore. However, it's my impression that the dedicated crown cutting tools have a bushing that goes in the bore so there is no turning against the lands/grooves inside the bore. Someone correct me if I have that wrong.

And I can't disagree with Virgil's recommendation. I'm liking my 21" .284 Win barrel quite a bit.

If you can get your barrel weight down to 2 lbs. 5 oz., then a standard Savage short action and factory stock (non-accustock) will give you a 6 lb. 2 oz. rifle. Topped with Talley rings and a 13 oz. scope, that puts my rifle right at 7 lbs. exactly, which is my upper limit for my hunting rifles.

pdshooter2
02-22-2022, 07:05 PM
OK, so you use a brass carriage bolt chucked in a drill press with the barrel held perpendicular. Liberal application of valve grinding compound. Seems like the brass bolt head would form to the muzzle/bore rather than the muzzle/bore forming to the bolt head? Why not use a carbide deburring tool rather than a brass carriage bolt? I agree the angle of the muzzle is not as important as being square and sure wouldn't want anything turning in the bore to screw up the last few inches of the rifling.

We agree that it is impossible to bore and rifle a barrel perfectly straight (tools drift), so I figure by cutting it, removes some of the drift. Virgil King (Houston warehouse) said 21.75 is optimum barrel length.

Bill

IN CONTEXT for a purpose built BENCHREST RIFLE...noting to do with a field or hunting rifle.

the 11 DEGREES MENTIONED comes from the exit nozzle of an rocket engine

pdshooter2
02-22-2022, 07:10 PM
you guys keep this up you will put real gunsmiths out of a job.
i own a manson crown tool kit. it is acceptable for rifles where a lathe is not practical.
all else go in a lathe, dialed in as close to 0.0000 as possible ,high speed, cut inside to out with very sharp carbide at 45*.
typically 2x the height of the lands.