Opinions on my crown

[rabiddawg]

My oldest Grendel has been giving me some accuracy problems for the past couple years. Initially I thought it was the scope(changed it) but now I am thinking something else is at fault.

Last weekend I took the Grendels out for a few rounds. One had a brand new AA 16" fluted barrel; here is the crown on it. I don't yet have a thread protector on it.


This is the crown on my oldest 16" AA running a flash hider of unknown origin.


This is it after I cleaned some of the carbon off


Do you guys see any reason to have this barrel recrowned?

I don't want to right a book on why I think something has changed but would like yall's thoughts on the condition of this crown or lack of one.

Ps. I bought this gun used and know nothing about it. Bought it as an AA built gun but there are no markings on the barrel it at all. It has served me well but I am losing confidence in it and may just buy another AA 16" and drop in it.

Thanks

[Texas]

Based upon the wear patter, the crown looks like it is not perpendicular to the bore.

If you have lost confidence, replace the barrel, in the long run you will come out ahead.

[rabiddawg]

I will add, in the photo there appears to be a bevel but I can't say there is actually one there.

I cleaned it up some more and changed the photo. To me it appears flat no beveled crown like the new barrel.

[Klem]

Looks fine from the photos. Maybe the bore needs a good scrub with solvent. Maybe it's been shown-up by the new barrel and is now the poor cousin. Without a bore scope to see the wear and regardless, it's down to the group sizes. You would know...How much bigger are the groups from when you first got it?

[rabiddawg]

The bore was clean.


I think I'm gonna go back out today, take my time and see what it can do. All I want from it is hunting gun accuracy; it's doing that.

[babue]

The bore was clean.


I think I'm gonna go back out today, take my time and see what it can do. All I want from it is hunting gun accuracy; it's doing that.

You could try cleaning the bore with J-B Bore Bright. You will be surprised how dirty the patches will be using it to clean the bore
especially in an old barrel.

http://www.brownells.com/gun-cleaning-chemicals/solvents-degreasers/bore-cleaning-paste/j-b-bore-bright-prod1161.aspx

For a really good cleaning I use both types. Brownells has a video on using it.

[LRRPF52]

If there are no markings on the barrel, I doubt it's from AA.

My older 16" is marked: "6.5 Grendel"

[204 AR]

I can't tell but it looks like there is a ding at 11:00 in the photo. At any rate it's surprising what difference a good crown can do. If you have someone that can do that for you I'd go for it. Can't hurt and it might help. If you don't, you'll always wonder if it needed it.

[Kilco]

For the cost vs aggrivation I'd get another barrel. You can screw around all day with X amount of loads and bullet possibilitys trying to get it to shoot.. or get another barrel knowing what you have. How has the new AA 16" been working?

[audredger]

What crown? looks like a bad cut-off and no crown thereafter!

[Klem]

What crown? looks like a bad cut-off and no crown thereafter!

That inner diameter step-down is a crown.

Crowns can be step-downs, angles or even a square cut with a ball and grinding paste for the ID of the bore. As long as there is some effort to square the muzzle after parting the excess then it's a crown. The three on the left are step-downs;

[ricsmall]

It's possible with that carbon build up from FH, it could've affected groups. Try it clean and report back. There was a slight ding at eleven o'clock it appears. That could definitely affect accuracy. If it still won't shoot ship me the barrel and a return label and I'll recrown it for nothing

Edit. I'm serious about the recrown. Also, as klem noted, crowns come in many different flavors. Most of the ones I do are cut with no attempt to bevel or break the edge at muzzle opening. There shouldn't be any burrs as long as I cut from inside to outside.
Richard

[rabiddawg]

Richard, that is a very generous offer but after shooting it a few times today(without the flash hider) I think I am going to order a new AA barrel in the morning. That way I will know what I have.

This afternoon, I shot my Bartlien barreled Grendel from 200 to 650 yards, I shot my TC contender 44 mag at 50 &100 and zeroed my son's 30/06 browning automatic at 200. I don't think it is my fault this gun isn't shooting to expectations.

Thanks for the input guys.

[rabiddawg]

What crown? looks like a bad cut-off and no crown thereafter!

That was my reaction upon seeing it and why I started the thread.