30 BR struggle is real

[jimmymac]

I’m with the gang that says put the chrono away and tune by the target. This whole ES and SD stuff in a short range gun is white noise.

Concentrate on powder charge and seating depth until you hit the right combo. A Boyer test using three shot groups is a simple way to find the answer. It never fails. I’d start jammed hard and back away about .003 at a time while simultaneously changing powder charge by .3 grains, find the load then fine tune from there.

If the barrel still wont shoot to your satisfaction then there is another problem somewhere. These things are notoriously easy to tune.

 

[RGRobinett]

Presuming that, in the info recorded on the first pic, .093" is supposed to be 0.0093", or, the neck-wall thickness, and you are using a bullet with, say, a .3084" "pressure-ring" (heel diameter) and a .330" chamber-neck (diameter), you'd have a loaded round diameter of 0.327", which is likely to "want" a .323" neck-size bushing. That's all the SWAG I'm good for today.
I probably failed the reading comprehension part - what was the problem with the first target posted? RG

 

[EEP]

The first target was awesome?? Assuming fire control, bedding and handling all good, I’m with the group on the ES, go with the target.

I gave up recently on a 17twist Bartlein, after trying 3 different bullets, 3 different powders 400rds later I sent it back to Bartlein. Of course they found a mysterious issue and sent back to me saying it should shoot “all measurements within their tolerances” It STILL would NOT shoot so I’m done with Bartleins. Got a Brux that’s shooting lights out. If it won’t shoot stop wasting components, money and time. Hard to give up on a heck of an investment but some barrels just won’t shoot they say…. that was a first for me.

 

[gunsandgunsmithing]

Last pic, number 1 bull @ 1.683. What's wrong with that? Looks like wind gotcha just a little to me. Many of the others look tune related. Put the numbers into a ballistics program. I don't think that much vertical will work out mathematically speaking, given your es. Yes, put the chrono away. I'm with Randy too, probably best with the .324 or maybe a .323. I'm assuming you had flags out when you were doing all of your testing. If not, scrap it and work around that .1683 load. I didn't see the powder charge. Nothing is written in stone but the general rule is that a 30BR very often likes heavy tension and a pretty hard jam. If you're not using flags though, you wasted pretty much all your time, components and bbl life.

 

[Jud96]

If you’re shooting short range score matches, then tune to the target. The ES isn’t going to shrink your groups. Even long range BR guys tune to the target, not what the chronograph says. I’m not a 30BR shooter, so I can’t help you with where to start on powder, but there’s some great shooters here that can help you. Listen to what they say. Make sure your have optimal clearance between your loaded rounds and neck diameter in your chamber. Too tight isn’t a good thing. You should be able to slide a bullet through a fired neck. I like at least .003 clearance from a loaded round and my chamber neck.

You should also try a different powder or a different lot of the same powder. Also try some different bullets. If you’re still not getting satisfactory groups after doing a powder charge test and seating depth test, then it may be time to look over the entire rifle. Check your fire control or have a good gunsmith that understands ignition look your action over. If after that nothing works, it could be a bad barrel.

 

[Doublejake]

Let's go a step at a time.
- What does the neck O.D. measure when checked with a .0001 micrometer over the pressure ring of the bullet when seated?

.3275

 

[RGRobinett]

A pal of mine recently got a "bad" Batrlein 30 Cal. barrel, chambered for 30 BR - it was bad until he put a different scope (from same manufacture) on it, whereupon, it became a HUMMER. RG

P.S.: At .3275" across bullet heel, I'd go straight to a .323" bushing - that alone will likely [substanitally] shrink the average group size!!

 

[Doublejake]

.3275

Yes I can slide a bullet in a fired round neck

 

[Jud96]

Listen to @RGRobinett , he knows the 30s as well as anyone.

 

[jimmymac]

A pal of mine recently got a "bad" Batrlein 30 Cal. barrel, chambered for 30 BR - it was bad until he put a different scope (from same manufacture) on it, whereupon, it became a HUMMER. RG

P.S.: At .3275" across bullet heel, I'd go straight to a .323" bushing - that alone will likely [substanitally] shrink the average group size!!

That is interesting. My buddy had the same thing happen.

 

[Doublejake]

A pal of mine recently got a "bad" Batrlein 30 Cal. barrel, chambered for 30 BR - it was bad until he put a different scope (from same manufacture) on it, whereupon, it became a HUMMER. RG

P.S.: At .3275" across bullet heel, I'd go straight to a .323" bushing - that alone will likely [substanitally] shrink the average group size!!

I will try some.

 

[Doublejake]

That is interesting. My buddy had the same thing happen.

I did swap scopes. Same thing.

 

[AlNyhus]

Have you tried another bullet?

 

[Bill Norris]

I’m with the gang that says put the chrono away and tune by the target. This whole ES and SD stuff in a short range gun is white noise.

Concentrate on powder charge and seating depth until you hit the right combo. A Boyer test using three shot groups is a simple way to find the answer. It never fails. I’d start jammed hard and back away about .003 at a time while simultaneously changing powder charge by .3 grains, find the load then fine tune from there.

If the barrel still wont shoot to your satisfaction then there is another problem somewhere. These things are notoriously easy to tune.

This method or something really close normally works for me with any caliber I try. Forget the chrono numbers (E S & S D) at short range. The 30BR is a no brainer with working up a load in a barrel/bullet combo that will shoot. The loads simply seem to fall together.

 

[Doublejake]

This method or something really close normally works for me with any caliber I try. Forget the chrono numbers (E S & S D) at short range. The 30BR is a no brainer with working up a load in a barrel/bullet combo that will shoot. The loads simply seem to fall together.

Nothing seems to be falling together lol. Everyone is saying put away the Chrono. But when a round is out from the rest of the group it also has a big ES from the rest.

 

[Doublejake]

Have you tried another bullet?

Not on this barrel. I have only tried 2 powders. LT30 and N130. .0093 brass necks and a bullet that measures.30895. If I use a .308 Bullet then I will have over 2th neck clearance. But it will be easy enough to give it a try.

 

[Websurfer]

Is the first photo - the 5x - of a target shot with your old barrel or new barrel?

 

[Dimner]

what is the bullet you are testing with?

 

[AlNyhus]

Not on this barrel. I have only tried 2 powders. LT30 and N130. .0093 brass necks and a bullet that measures.30895. If I use a .308 Bullet then I will have over 2th neck clearance. But it will be easy enough to give it a try.

The 'big' bullets certainly will shoot...one of my dies makes such a bullet. Because of being snug in the freebore, they can also fake you out by the 'feel'. Have you verified your seating depth using the Touch Point method?

Also, Ive tested neck clearances to .004+ with no accuracy loss. I set up my necks to have .003 with my .3089 bullets.

 

[Sandstorm]

I did swap scopes. Same thing.

Time to swap barrels then..or bullets, didnt realize
you hadnt tried a different bullet.