hey guy I got a lot of muzzle run out .065 on the muzzle end of my barrel after the chamber is dialed in how much is to much. Also I am not bending the barrel I had it in a Spyder backplate then swapped it over to a 4jaw and still .065 run out any thoughts?
Gunsmithing Muzzle runout
- Thread starter themayor
- Start date
I dial barrel in thru the headstock, spider on the outbore and a 6 jaw chuck. Its not uncommon to see that kind of runout on the muzzle end. I dont care what the muzzle end is doing as long as I know im running .0002 or less at the throat area and ass end of the chamber. Drills wander over the 27"+ when they are making a barrel.
Not a big deal. My F-Class rifle is .052” out at muzzle end. Took it to 1000 yd. benchrest match and shot 5” group. It won’t be as easy to tune load for as a straight barrel, but will still get job done. If you want a straight barrel, buy a Hawk Hill, they are straightest barrels I’ve seen.
Like most, some runout is normal but that seems excessive.....not sure what you can do about it but make sure and time the high to the top or bottom of the receiver..... mark the high point on top of the blank and index the tennon until it's at 12'0 clock.... holler back if you got any questions
Ya that’s what got me I know some runout is normal but .065 is a lot when spinning it in the lathe is like a unbalanced tire
@cwinner is absolutely correct, clocking muzzle to 12 O’clock or 6 O’clock will make life easier.
Why don't you dial it in so you are running .0002 or less at the throat area and the muzzle end?
theres no way in hell you're doing that without bending/stressing the barrel. indicate the throat/chamber and dont worry about the muzzle. time it out and go on. it has zero effect on accuracy.
Why not?
Why would you be bending or stressing the barrel any more by having the muzzle and throat dialed in vs. any other two spots in the bore?
Because if the bore is curved, however slight, you simply can’t get two sections(two points at each end) of bore to run coaxially. You could get two individual points at each end to run coaxially, which isn’t the same thing.
But you absolutely can have the throat and muzzle dialed in. Many bencherst builders do this.
You’re a good builder and I’ve seen a lot of your work rubicon but why would I even want to attempt to push a barrel straight at 3 points to get the muzzle to run out at zero? Two coaxial points in the chamber/throat are indicated at zero tir...a muzzle the runs out .065 and you’re going to make that zero tir as well? How so?
You indicate two points, throat and muzzle, to zero. The third point is cut to zero.
Looks like Edds answered it. You get the two points you choose to run true, which ever those two points may be, then machine the chamber to be in line with them.
And I won’t argue which method is best, because I don’t think it can be qualified on target. Each builder needs to do the method they feel is best and works best for their set up. I have built many both ways and have settled on what I like best.
Ah I get how your doing it. I can’t say I see a reason to do that. I would highly doubt there would be any gain to it over coaxial at the chamber. My contention at the muzzle end would be are you going dti in the bore or using a rod?
To each their own for sure. Tons of ways to skin cats. I remember when people argued over going coaxial inside the bore vs rods etc not so many years ago.
To each their own for sure. Tons of ways to skin cats. I remember when people argued over going coaxial inside the bore vs rods etc not so many years ago.
You’re still talking about two individual points, which depending on the curvature of the bore, is a compromise at the chamber end.
Here’s and example. I’ve dialed in the breech end to be coaxial across 1” (two points, one inch apart). I’ve done this with a set-tru style chuck with an outboard spider, or a TBAS chuck. What other adjustment do I have to affect the bore at the muzzle end, to run coaxial in the same manner as the breech, that doesn’t involve compromising the breech end alignment, and doesn’t stress the barrel?
Genuine question.
A little off topic, I borescoped a new prefit barrel for a savage the other day. Chamber was obviously cut off center, gun shoots lights out. Makes me think Im to anal about my setup and cutting chambers but I have had very good success with my setup.
Casey
Casey
Thats the method I've used for many years and it has worked very well for me. Im not worried about what the muzzle is doing, I like to dial the chamber end and throat in to .0002 or less runout. I drill and prebore the chamber and time the muzzle end runout to TDC.
Casey
I’m not saying you are. I think I took what you said to mean that dialing muzzle and throat is superior to dialing the throat-lead. It seems you kind of clarified that to state you do what works for you, but many ways work. ??
Personally I think accuracy is in the barrel, like intrinsic to the barrel. It’s kind of like guitars. You can have a pile of them made of the same materials to the same standard and dimensions and there will still be a fairly wide spectrum of “niceness” to them.
