Barrel Re-Crowning

[Losing_Sanity]

I have a rifle that I have tried glass bedding and installed a Timney trigger. Also changed scope and scope mounts. Still can't seem to get to good of a group with test reloads. I was thinking about possibly trying to re-crown the barrel. I have never re-crowned a barrel and have a few questions. If you can't see an issue on the crown, could there still be that much of a problem on a new rifle? If you have done this or had it done before, How much of a difference it has made? How difficult is it to do?
I'd appreciate any advise you may have.

Larry Potterfield makes it look like it's no big deal.

 

[Bigjay73]

I'd take it to a good gunsmith. He can inspect the crown, and the rest of the barrel. If the crown is damaged, reworking it isn't something I'd do diy.

 

[UP North Farmer]

A lathe is the best way to recrown the barrel. A gunsmith would be your best bet. It usually doesn't take long or cost much. Chasing repeatable accuracy can be a real pain with some rifles.

Jeremy

 

[cahunter805]

What kind of rifle is it?
Most gunsmiths should be able to recrown the barrel quickly and not to expensive.

 

[Losing_Sanity]

What kind of rifle is it?
Most gunsmiths should be able to recrown the barrel quickly and not to expensive.

It's a Ruger Hawkeye. I've had it for a while but I got frustrated with it and put it away. Now I think I'm ready to try again and I saw some folks talking about the crown. Thought maybe I would the crown next.

 

[Dr. Vette]

I have seen other articles like this one, but it makes you wonder just how much the crown affects the accuracy:
https://rifleshooter.com/2018/03/do-rifle-crowns-matter-does-a-crown-effect-accuracy/

If the crown looks good, I would look elsewhere.
Your rifle may not like the bullet you choose, or the powder, or some other factor.
Some are just a PITA to find an accurate load.

 

[ImBillT]

I’d have it done on a lathe if you get it re-crowned, but I also think your problem probably lies elsewhere.

 

[375H&H]

It is worth looking into the crown, but I find it hard to believe you could screw the crown up enough to actually do damage and affect hunting accuracy short of taking a thread cutter to it.

Even if the crown was damaged severely, the gases will still leave the barrel in the same pattern and the rifling will grab the bullet the same each shot and thus you should still be able to group.

 

[Losing_Sanity]

Thanks everyone for the advise and the article. I really appreciate it. I'm not sure what direction to go. I guess some rifles just don't shoot well for many reasons. I have tried several bullet manufactures and weights, as well as powders and primers. It still might be worth having a gunsmith take a look at the crown. As the article said, "Does a rifle’s crown affect accuracy? Yes, it can. Bear in kind what accuracy means, how close we are to the target. We can have a precise rifle that isn’t accurate and an accurate rifle that isn’t precise. If you have a zero on your rifle and damage the crown you’ll most likely have a POI change which in turn affects accuracy".

The challenge continues...

 

[std7mag]

I hope you did not free float the barrel when you did your bedding.
Rugers have a pressure point in the forestock. Was put there from the factory.
I'd try some folded up paper about an inch back from the forestock tip and see what she does.

 

[D4570]

Did you simply try different bullets, powder, primers?
Some rifles just don't like some load combos.
Maybe your trying to use a bullet with the wrong twist.
All are cheep and easy fixes. I have never seen or had a bad crown ,
in 45 years of shooting. Try slowing down or speeding up a load.
After "Bedding" the harmonics may change dramatically .
Personally I would try that first before making permeant changes to the barrel.

 

[Losing_Sanity]

I hope you did not free float the barrel when you did your bedding.
Rugers have a pressure point in the fore stock. Was put there from the factory.
I'd try some folded up paper about an inch back from the fore stock tip and see what she does.

It didn't shoot too well before the bedding. I'm sorry if I inadvertently insinuated that I performed the bedding on it. I didn't, my kids had a gunsmith do it for me as a fathers day gift. I have only bedded one rifle and I was kind of apprehensive to do a brand new one.
Yes, I believe it is free floated. But wouldn't a gunsmith have known how to do it properly? He is a very well known and recommended gun smith in the area? I have some reloads that grouped what I figured was somewhat good enough that I stuck with until I was in the frame of mind to try again, so I will try your suggestion and see if it affects anything. I missed a monster of a buck with them at 260yrds from a supported rest. Somewhat good enough really ain't good enough. Hard to even look at that rifle without thinking of the "once in lifetime" opportunity missed.
I went back to my tried and true 7mm STW in Remington 700 and put that rifle up. The tack driving, deer slayer!

 

[Losing_Sanity]

Did you simply try different bullets, powder, primers?
Some rifles just don't like some load combos.
Maybe your trying to use a bullet with the wrong twist.
All are cheep and easy fixes. I have never seen or had a bad crown ,
in 45 years of shooting. Try slowing down or speeding up a load.
After "Bedding" the harmonics may change dramatically .
Personally I would try that first before making permeant changes to the barrel.

Yes, I have tried all of that. The twist might be an issue and that would narrow down my options for bullet selections if I could find a nice load.
I really have never found a bad crow either. But in some of the post here on HT, I recently read some are checking the crown and re-crowning the barrel. That's why I am considering it.

 

[Don Fischer]

A couple of my 700's came with that fore end pressure in the stock. Removed it and free floated the barrel and they shot a lot better. Don't know why company's put that in there, I've never seen it work at all. Rather I'd solid bed the barrel full length, that worked great on a 7mm mag I had years ago. Neat video on crowning. But I too would take it to a gunsmith. The end of the barrel does need to be properly in line with the bore!

 

[std7mag]

Twist for anyones 7mm Rem Mag, more than likely runs from 1:9-1:10.
160 gr bullets should have no problem stabilizing.
I'm taking it you have rulled out scope/ring issues. As in rings properly torqued, not just "yeah, that should hold it" overtorqued.
Rings aren't pinching the scope?
Action screws properly torqued? (I've seen
them fall out of peoples rifles)

After checking all that, let someone else shoot it and compare notes.

If all else fails, i'm always looking for another Ruger.. :

 

[ImBillT]

There are sooooooo many little things to check. I’m sure I’ll leave some out.

Make sure that all the base screws tighten down the base, rather than bottoming out in the screw hole and leaving the base slightly loose. Check each screw individually.

Make sure that when the scope rings are tightened there is still a gap between them. With enough lapping you can make it so that the two halves touch and aren’t able to firmly clamp the scope.

Make sure the rings are firmly securing the scope. Rings that are too smooth from lapping can allow imperceptible slipping. Friction tape can help.

Flip scopes between the gun in question and a gun that shoots great to check the scope(or find someone with a scope checker).

Check the bedding by removing all but one action screw, and tighten that one screw. The action should not move, but rather be as firmly placed on the bedding as if all screws were tightened.

Make sure that none of the action screws protrude to high either preventing the action from being tightened, or coming into contact with a bolt. I once swapped stocks and had a gun go all to ****. Switched back and it was shooting great. I discovered that the front action screw was pushing up against the bolt just enough to cause a problem and leave a shiny spot on the bolt, but not enough to prevent the bolt from closing. Ground the screw and it shot great.

Seat a bullet long and keep going until the lands leave a mark on the bullet that is the same length as it is wide. Check each mark on the bullet. If there are different from one another it is the result of cleaning rod damage. If it’s nearly impossible to get a mark on the bullet, the throat is becoming eroded.

Have it bore-scoped, and possibly slugged by a gunsmith.

Check runout, and neck tension on your loaded ammo. Sometimes a bad set of dies can cause issue. (I’m no longer a fan of Hornady dies, but it’s by no means limited to them)

Almost any sane powder/bullet combo will shoot in the neighborhood of 1-MOA from an accurate gun with a little load development.(velocity and seating depth)

Some guns/barrels just won’t shoot.

Outside of obvious crown damage, recrowning for accuracy purposes is mostly something a match shooter might do because he thinks his barrel MIGHT be slipping, and he can’t get a new barrel built up before the season is over...or he has a lathe and he’s bored.

 

[Losing_Sanity]

Check runout, and neck tension on your loaded ammo. Sometimes a bad set of dies can cause issue. (I’m no longer a fan of Hornady dies, but it’s by no means limited to them)

Almost any sane powder/bullet combo will shoot in the neighborhood of 1-MOA from an accurate gun with a little load development.(velocity and seating depth)

Thanks for your input. I have checked most of what you suggested.
"Check runout, and neck tension". That is something I have not considered. Can you explain "Run out" so I understand completely? Is there a minimum of "seating depth"? I have in the past became concerned with this in an effort to get the bullet to reach the lands. This is something I have considered for this rifle.

 

[antelopedundee]

Thanks for your input. I have checked most of what you suggested.
"Check runout, and neck tension". That is something I have not considered. Can you explain "Run out" so I understand completely? Is there a minimum of "seating depth"? I have in the past became concerned with this in an effort to get the bullet to reach the lands. This is something I have considered for this rifle.

Zero run out would be an imaginary line running through the center of the primer up through the middle of the case and the middle of the base of the bullet. It continues on through the bullet. If it passes through center of the bullet tip then there's zero run out. If the bullet gets seated canted or lightly tipped to one side then you'll have run out. In a word it's all about CONCENTRICITY!

 

[std7mag]

Hmmm...
Hadn't thought of it that way.
In laymans term the runout is the bullet seated crooked in the case. Checked by spinning the round with a dial indicater on the bullet.
If the cartridge has excessive runout then it would enter the rifling crooked, affecting accuracy.

For common cup and core bullets, i've typically loaded 0.020" off the lands for best accuracy.

 

[ImBillT]

Runout is the lack of alignment between the bullet and case. You can measure it by placing the case in a v-block and putting a dial indicator on the bullet, then spinning the case in the block. If it’s really bad, you can roll the loaded cartridge across a table and see the tip wobble. It doesn’t always cause problems. I’ve seen great groups shot with bullets seated visibly crooked. GENERALLY runout is less important when a bullet with a long tangent ogive is seated long in a case with a thin neck and low neck tension. With very little of bullet in the case neck, and plenty of contact with the lands, the lands can align the bullet to themselves to some degree. Runout becomes a bigger issue when the above factors go the opposite direction. More bullet in the case neck, increased neck tension and secant ogives can make it difficult to realign the bullet when it’s chambered. Jumping a bullet instead of jamming causes that realignment to take place very rapidly while the bullet is moving. Secant ogives interface with the lands much more abruptly. Thick necks require more force to realign a bullet even with low neck tension.

High bullet runout can be caused by dies that don’t properly align a bullet with the case, or by brass with necks that are thinner on one side than on the other.

Actual magnitude of neck tension is not as important as consistency of neck tension. Inconsistent neck tension can come from inconsistent neck thickness from case to case, or inconsistent hardness. Mixing brands, or cases that have been fired ten times with cases that have been fired once will give you differing neck hardness. Harder brass springs back more after sizing than soft brass, and thus gives you inconsistent neck tension. High neck tension, and thick necks tend to exacerbate issues with inconsistent neck tension, so even if the amount of neck tension isn’t the real culprit, turning necks and changing bushings or expander buttons can eradicate issue with inconsistent neck tension.(turning necks can improve runout as well, but you really shouldn’t have to turn necks to get well under 1-MOA) Check your sized case neck diameter, and if it’s much more than .001” smaller than your bullet, you MIGHT benefit from reducing your neck tension a little bit. Check your expander button and see if there’s any chance you got one that was smaller than spec.

Also, even with little to no bullet runout a cartridge that sits loosely in a chamber leaves the bullet misaligned to the bore. Seating out long enough to touch the lands, especially with a tangent ogive bullet, can properly align the cartridge in the chamber to some degree. Jamming a bullet into the lands is not always recommended for hunting loads because it’s possible to open the bolt and come out with an empty case, an action full of powder, and a barrel with a bullet lodged in it. Partial or neck sizing can help align the cartridge to the chamber. Both partial sizing and neck sizing can result in a stiff bolt close and lift, so again, they are often not preferred for hunting. Those techniques have fallen out of favor among competitive shooters as well, but competitive shooters are using custom chamber reamers and custom dies that allow them to full length size and still have a near perfect fit in their chambers. In a factory chambered rifle, it’s possible to have situation in which sizing the shoulder back enough to chamber easily results in sizing the case diameter down too much and thus leaving it a little sloppy.

Make sure your seater die isn’t set up where you’re slightly crimping the case mouth. Although that doesn’t usually result in great accuracy even when done properly, if you happen to be very very close to the crimp portion of a seater, and you have inconsistent case lengths, you can have some bullets that are barely crimped, and others that are not crimped at all. Also check your case lengths. If they need to be trimmed, it’s possible to have some case neck in the throat, which will result in a very similar crimping. If it gets excess it can lead to serious problems with overpressure.

Some guns, and some barrels, just won’t shoot.