Question About "Bullet Test"

[Radjxf]

I've seen mention of the "bullet test" to evaluate muzzle wear. All of my guns pass, even a 64 y/o M1 Carbine. So I just picked up an old Ruger 44 Carbine. Shoots about 4" to the left at 50 yds with the irons and the rear sight adjusted pretty far to the right. So I look at the bore, looks shiny with good rifling. Rifle looks as if it hasn't been shot a whole lot for it's age.
Problem is, the crown has some tiny nicks, and when I drop a loaded round into the muzzle, it goes in all the way to the brass case! So is the bullet test valid for any gun regardless of chambering? Should I sell this thing and move on? TIA.

 

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For top accuracy I'd get the crown lapped, but in a 44mag carbine it ain't a long range tack driver. How big is the group that is 4 inches left? If the group is good, keep the gun & look at the front sight to see if it has been moved, if it has move the sight back, that will fix your point of impact.

 

[Radjxf]

Groups are way left, but around 2" or so (limited by my eyesight with the irons).
I had considered lapping the crown myself, or buying a crowning tool from Brownells, but didn't want to spend a ton of $.
The front sight looks perfectly centered, the rear is moved way to the right to compensate for the POI being left.
I have an old red dot sight lying around. Might just put that on and correct the situation that way. Thanks for the advice.

 

[rcmodel]

The bullet test only works if you use a bullet.

A loaded round has most of the full diameter bullet inside the case.
The part sticking out is rounded, or tapered, or otherwise smaller then the bore, so it is meaningless whether it fits in the muzzle or not.

You can lap the crown yourself with a couple of very inexpensive items from the hardware store.

Get a large, round-head brass screw or bolt.
And a small can of fine valve grinding compound.

Put the screw in an electric drill, coat the head and muzzle with compound, and go for it.

Keep the drill moving in elliptical motions all the time so the round screw head is not in contact with the muzzle in any one place.

Once the crown is lapped to your satisfaction, clean the bore throughly to get all the grinding compound out of it.

rcmodel