Barrel vs bullet

[Jmac604]

Is there any equation, rule of thumb, etc to determine if bullet X will shoot accurately from barrel Y?

The reason I ask is this:

My favorite 30-06 has 24" Hart barrel and is very accurate and it is sighted in at 100 yards;

When I shoot Hornady 165 grain Interbond BT or Remington Core-Lokt, accurate and consistent. All groups consistently within 2" MOA;
When I have shot 165 grain Federal TBT or Federal TC, accurate but inconsistent. How I define inconsistent is that, for example, I will fire a group of 3 rounds and 1 will be within the 2" MOA while two will be fly aways or two will be within 2" and the 3rd is a fly away, etc etc.

Any advice or suggestions? This is getting somewhat expensive and frustrating to figure out.

Cheers..

 

[Kelly Timoffee]

Best suggestion in this case is to get a friend to try shooting the same shell/load and see if the results are the same and then decide if you need to try different ammo.

Sometimes it is the guy having a bad day also.

Sometimes only a few loads will work.

Being that you have a custom barrel it would be best to hand load to take advantage of the quality increase.

 

[stubblejumper]

Is there any equation, rule of thumb, etc to determine if bullet X will shoot accurately from barrel Y?

The reason I ask is this:

My favorite 30-06 has 24" Hart barrel and is very accurate and it is sighted in at 100 yards;

When I shoot Hornady 165 grain Interbond BT or Remington Core-Lokt, accurate and consistent. All groups consistently within 2" MOA;
When I have shot 165 grain Federal TBT or Federal TC, accurate but inconsistent. How I define inconsistent is that, for example, I will fire a group of 3 rounds and 1 will be within the 2" MOA while two will be fly aways or two will be within 2" and the 3rd is a fly away, etc etc.

Any advice or suggestions? This is getting somewhat expensive and frustrating to figure out

I don't consider 2MOA to be at all accurate. As to why some loads shoot better in a given firearm, it's just the way it is, due to harmonics, and other factors. And no, unless the rate of twist is totally unsuitable for a given bullet length, you can't usually predict which bullet will shoot more accurate in a given rifle, without actually shooting the loads.

 

[Jmac604]

I don't consider 2MOA to be at all accurate. As to why some loads shoot better in a given firearm, it's just the way it is, due to harmonics, and other factors. And no, unless the rate of twist is totally unsuitable for a given bullet length, you can't usually predict which bullet will shoot more accurate in a given rifle, without actually shooting the loads.

Neither do I...the 2 MOA was an example to illustrate my problem.

 

[sheephunter]

If you are getting flyers I doubt it's a barrel/bullet issue. I'd be looking at other causes. If the best you are getting is 2MOA out of a custom barrel, I think you've got bigger problems somewhere else.

 

[c-fbmi]

It is refreshing to see someone post 2 moa as reasonable accuracy from a hunting rifle, which is of coarse it is. As far as liking different loads and not liking others is just the nature of firearms and is completely normal. 2 moa with factory ammo is acceptable, sometimes it gets better but sometimes it don't and is not anything for the average hunter to be concerned with. Consistent 2 moa still equates to a heart shot on a moose to 300 mtrs, does the average hunter using factory ammo and likely never shooting at game beyond 250 mts really require greater accuracy? According to Roy Weatherby 3 moa is acceptable hunting accuracy......................

 

[sheephunter]

I've honestly never owned a hunting rifle that shot worse than 1.5MOA and I sold it. I'd expect sub MOA accuracy from a rifle with a custom barrel on it.

 

[Juster]

If you are getting flyers I doubt it's a barrel/bullet issue. I'd be looking at other causes. If the best you are getting is 2MOA out of a custom barrel, I think you've got bigger problems somewhere else.

Bedding perhaps.
Anyway, there is there no equation, rule of thumb, etc to determine if bullet X will shoot accurately from barrel Y.

 

[-Savage-]

I'd expect sub MOA accuracy from a rifle with a custom barrel on it.

At the rifle range, ALL of my Sako rifles (with factory barrels) shoot sub-MOA. But they only do this when I am having a good day. Indeed, when I've just had 2 mugs of strong coffee and/or am over-tired or stressed out, NONE of them do. LOL.

But, having said that, deer-hunting here on Vancouver Island typically involves firing a snap-shot from a standing position on a logging road at the comparatively large chest cavity of game less than 100 yards away. So really, here, during hunting season, bench-rest sub-moa accuracy is more an academic than a practical concern.

 

[sheephunter]

At the rifle range, ALL of my Sako rifles (with factory barrels) shoot sub-MOA. But they only do this when I am having a good day. Indeed, when I've just had 2 mugs of strong coffee and/or am over-tired or stressed out, NONE of them do. LOL.

But, having said that, deer-hunting here on Vancouver Island typically involves firing a snap-shot from a standing position on a logging road at the comparatively large chest cavity of game less than 100 yards away. So really, here, during hunting season, bench-rest sub-moa accuracy is more an academic than a practical concern.

Not saying you need that kind of accuracy but from a custom barrel I'd expect it. My only point being that I think there is something else going on with the OP's rifle other than just it doesn't like a particular bullet. Most rifles have a lot of accuracy potential...the trick is to figure out how to get it.....human factor aside.

 

[-Savage-]

I can only agree with you. Most rifles are potentially far more accurate than the person pulling the trigger. Especially when they have a custom barrel. So yes, in the OP's case, something else is going on.

 

[Jmac604]

I can only agree with you. Most rifles are potentially far more accurate than the person pulling the trigger. Especially when they have a custom barrel. So yes, in the OP's case, something else is going on.

I hope not but it is something I will check into as well as adding in some dry fire exercises. I can accept that the barrel might not 'like' certain ammo; it's the inconsistency thats driving me crazy from a custom barrel. As with sheephunter I do expect better with that than a factory one.

I thought at first it may have been barrel twist vs ammo weight. IE 1:10 twist with 165 grain bullet but some Google checks indicate otherwise.

Anyway..I am on vacation soon and will put this problem aside till I get back.

Thanks to all the posters....the info was appreciated.