Gunsmithing Barrel alignment

[Cuzz]

Ive been told that no barrels are perfectly straight and that they need to be installed so that they direct the bullet up or down ( preferably up i guess) instead of left or right. Does anybody know if this is true?
thanks

 

[308pirate]

Ive been told that no barrels are perfectly straight and that they need to be installed so that they direct the bullet up or down ( preferably up i guess) instead of left or right. Does anybody know if this is true?
thanks

The part about barrels not being perfectly straight is true. In fact, NOTHING man made is perfectly straight.

The part about clocking the barrel so it points up being necessary is not necessarily true. Scopes adjust in two dimensions, so I don't see what difference it makes

I think this thread will become ten pages of opinions with zero evidence to back them up.

 

[CoryT]

They are certainly not straight, and it's nice to clock the barrel centered and curve up, as it preserves windage and elevation, but it's not essential. Only custom makers do it, and not all of those. Given how far off square the factory actions and scope base screw holes are, that's probably the least of your problems on a factory gun.

 

[Rubicon Precision]

Curious how many builders that “time” the barrel, verify it is still “timed” when not stressed between two independent chucks, and freely hanging from a single end at the receiver.

 

[CoryT]

Guess that depends on how you figure the curve in the first place. If you center the barrel for chambering in a four-jaw using a long indicator or rod, then check/mark the position of the high point at the muzzle end, you should have that hold up at installation.

 

[Rubicon Precision]

Guess that depends on how you figure the curve in the first place. If you center the barrel for chambering in a four-jaw using a long indicator or rod, then check/mark the position of the high point at the muzzle end, you should have that hold up at installation.

Just because the muzzle is at the high point, that doesn't guarantee the bore is facing in an upward attitude.

 

[Rubicon Precision]

I think this thread will become ten pages of opinions with zero evidence to back them up.

I'm betting this^

 

[308pirate]

Curious how many builders that “time” the barrel, verify it is still “timed” when not stressed between two independent chucks, and freely hanging from a single end at the receiver.

Very few, I bet.

 

[DangerRanger]

@DAVETOOLEY

Enlighten us?

 

[Supersubes]

Curious how many builders that “time” the barrel, verify it is still “timed” when not stressed between two independent chucks, and freely hanging from a single end at the receiver.

You dial in the muzzles, so you’re taking slightly different approach to accomplish basically the same thing arent you?

 

[DAVETOOLEY]

I don't time muzzles. I indicate them in. I can put a half a dozen barrels on the same action and they print to within an inch of each other at 100 yds. Seems like there's some consistency there.

 

[Rubicon Precision]

You dial in the muzzles, so you’re taking slightly different approach to accomplish basically the same thing arent you?

Yes, sort of, and no, sort of....

 

[DAVETOOLEY]

Those that time the muzzle are concerned about the angular misalignment of the throat. I'm not. My focus is on concentricity. I did the calculations once for a chamber that wasn't/timed aligned with the bore over the length of the chamber. We have very good barrels these days .0005" to .0010" is not much. Lot's of zeros beyond the decimal point. Concentricity we can measure and see. Angular misalignment over the length of the cylinder section of the bullet is very difficult to measure. Then lets consider the runout in the ammunition.
YMMV

 

[Hateca]

Lots of ways to skin a cat that can get lost on translation. Outside dimensions of the barrel or where it points makes no difference to me it’s the bore that is important to me and how I dial indicate it in. The profile of the barrel could be square for all I care, the bore is where it’s at.

 

[Danny1788]

Those that time the muzzle are concerned about the angular misalignment of the throat. I'm not. My focus is on concentricity. I did the calculations once for a chamber that wasn't/timed aligned with the bore over the length of the chamber. We have very good barrels these days .0005" to .0010" is not much. Lot's of zeros beyond the decimal point. Concentricity we can measure and see. Angular misalignment over the length of the cylinder section of the bullet is very difficult to measure. Then lets consider the runout in the ammunition.
YMMV

I think it depends on how you setup your barrel to chamber. If you dial in the muzzle and the throat and then prebore to the throat then it shouldn’t matter one bit, if you only dial in the chamber end and 2.75” in with your dti then time the muzzle and run the chamber Reamer strait in... Just how I see it

 

[Hateca]

I think it depends on how you setup your barrel to chamber. If you dial in the muzzle and the throat and then prebore to the throat then it shouldn’t matter one bit, if you only dial in the chamber end and 2.75” in with your dti then time the muzzle and run the chamber Reamer strait in... Just how I see it

Exactly. It all depends on the set up and how the chamber is going to be cut. Like I said there is more then one way to skin that cat.

 

[Cuzz]

Well i dont understand a lot af what yall are saying but its still interesting. Thanks for all your angles!!

 

[Danny1788]

Exactly. It all depends on the set up and how the chamber is going to be cut. Like I said there is more then one way to skin that cat.

If they don’t understand what we are talking about then it’s over their heads lol

 

[Cuzz]

Yep, most of its over mine.