Some will disagree, but I don't think your crown is the problem here.

However, if you want to address it, you can use rubbing compound for grit, and either a glass marble rolled around with the palm of your hand, or a round head brass screw powered by a hand drill to touch up your crown.

In any event, it's only the opening of the bore that could be a problem. The dings on the muzzle will have no effect on accuracy.

If using the marble and your hand, it will have enough variation. If using the brass screw, roll it around a bit so it doesn't take too much off in one place. You only need to even up the edge of the bore.

After that, it's the usual suspects....

Has your rifle been more accurate in the past than it is now? Are the stock screws firmed up (but not over tightened)? Same for the scope base screws--can't tell if your rifle is wearing a scope from the pics.

Have your eyes changed? Are you using a pad, or at least your hand under the fore end if shooting from a bench.

Good luck.

 

Is the gun a take down ?

 

I went through this with a 7mm Remington Rolling Block, 40 years ago. Its rifling was washed-out at the muzzle and for about an inch behind. Me and a gunsmith pal cut it back two inches, carefully re-crowned it and remounted a ramped bead front sight. The accuracy improvement was astounding.

I believe yours has the same problem. I blew your photos up and what I am not seeing in any of them is sharp lands, right up to the crown. I'd give it the same treatment as the rolling block.

 

I just remembered I have a "borescope" cell phone flexible probe camera thingy I got on the cheap that worked pretty good for sticking in small engines, I will see if it fits the barrel tomorrow and see if I can get some pics of the insides of the barrel on both ends.
Thanks

 

Where the bore meets the crown, it looks okay, without being able to feel it. I agree with the previous post, that it may be a rifling issue.
Andrew

 

Here are pics from the bore scope thingy
I had to take a pic of the view on my tablet.
It was only $20 you get what I paid for
The last pic is about 1/2" inserted
😳

 

Have you scrubbed the bore with JB Bore Paste? Get the barrel clean down to bare steel, fire 5 fouling shots, then shoot for a group. I don't like the way the bore looks. Give the old girl a thorough cleaning.

 

Yeah
Cleaned several xs with Shooter choice mc7 , I have their extreme copper remover, going there next.
Bore scope thingy shows some pretty rough looking inside.
Here is one from bore then a couple more from inside.

 

I question the crown because the fact it is so "round" with no visible humps or tread .
Attached is a pic if my A&B 250 savage that has only 40 rounds thru it.
Very defined humps or tread if you will.
Not sure if past cleaning rods scrubbed the crown down or just what?
Just looks well wore/polished ect
I use a plastic groomer insert to "protect" the crown on 99s
Any thoughts are appreciated
Thanks

 

I'll agree that on your 250 I can see the lands and grooves while on the 358 I can't (closeups of muzzle) on top of that the bore of the 358 looks pretty bad to me. Might have the muzzle given a slight counter bore and try polishing the bore with JB bore paste.

 

Looks like real bad leading to me.

 

Had a bore that someone fired lead, then jacketed bullets, over and over and never cleaned, it took a lot of elbow grease and bore brushes to get the bore clean and back to being reasonably accurate, that bore looks plated and ugly to me.

 

Leading ?
Guess I never thought about that.
🤔
Anyone have a good lead removing brew you could recommend?
Thanks

 

Hoppes #9 and 0000 steel wool wrapped around a bore brush.

 

Monkeymaster,

That 250 Savage muzzle is exactly what a healthy barrel and crown should look like.

That poor 358 looks like Bubba put a tapered conical stone in his Black & Decker and tried to 'improve' it. A vigorous cleaning sure wont hurt it and will at least reveal the condition of the bore, an inch or two behind the existing muzzle.

I wouldn't worry much about the appearance of the rifling behind the muzzle if the lands and grooves are healthy, an inch or two inside. The old 7mm rolling block I shortened had a downright ugly bore, but once shortened, it had plenty of rifling left to give it's bullets the all important goodbye kiss necessary for good accuracy.

 

Softball size groups

4" at 100 yards? That should kill a deer.

Leading ?
Guess I never thought about that.
🤔
Anyone have a good lead removing brew you could recommend?
Thanks

Hoppes #9 and 0000 steel wool wrapped around a bore brush.

I prefer to use a few strands of copper Chore Boy scrubber.

..

 

4" at 100 yards? That should kill a deer.





I prefer to use a few strands of copper Chore Boy scrubber.

..

I agree. I've used stands of copper Chore Boy (not the regular Chore Boy) wrapped around brass brush to remove leading from my 1911s from shooting lead bullet loads.

 

Started cleaning bore today
Must be lead, sure getting a lot of grayish crap out of it.
Bore looking better,but I want to put some more patches through until it is not so grayish black.

 

That bore is excellent and should be a fine shooter. Good work.

 

Two additional comments. Your 99 is a model 99F; it has a thin feather weight barrel. It does not take many shots to heat it up, so that could throw off the groups, too. Also forearm pressure; some of us put a rubber washer on the inside of 99 forearms on the forearm screw; has often made a significant difference in groups.

 

Update

O ring trick, I use a 1/2"x1/2" piece of roofing rubber, with a hole punched out for the stud/mounting screw, a little more meat than an o ring, with a little hand sanding the forearm is free floated enough for a $ bill to slide freely all around other than this 1/2"sq patch.

Shot the 99 today after two good cleaning sessions of Kroil and JB bore paste.
Significantly better.
50 grns of win 748 and 200 grn Hornady rnd nose shot very good.
Will probably be my go to load this season.
Tac and 200 grn Hornady spt was not great.
IMR 4198 and 180 grn Speer shows some promise, although shoots way high.
This combo needs some more development.
I have become a Kroil JB Paste believer!
Thanks to all

 

 

Here is the piece of roofing rubber I use in lieu of the o ring.
The results.
Thanks to everyone's in put.
Again
I really, really am impressed with the JB bore paste and Kroil.
I highly recommend this method if you have a gun not shooting and stressing you out.
Thanks to all.