280AI range results

[CBH Australia]

I have only encountered neck collars (donuts) when extreme forming/re-sizing, or once on many reloads of same few cases. Our solution was align-boring to .005 over bullet diameter. We now carefully re-size neck with collet dies!

are you meaning Bushing dies? Or the Lee Collet dies?

I have considered trying bushing dies.
My rifles and loads are acceptable for hunting but it's just a learning curve and I would like to get the best out of it. If I have a hunting load at say .5 or better it's just going to be a little more accurate as the distance increases.

I've always said an accurate rifle will compensate a little for a little human, technique or ability , error or external effects on the shot.

Plus I just want to head out with the confidence of having a .5moa rifle and have the bragging rights.

I've spent more on this rifle and associated components than others I would like to see something in return.

 

[Evilsports]

Can anybody recommend a way to a resize a case to modify without necking it down?

I took three pieces of fired brass and FL resized it so they would accurately represent the casing that I am loading. I put it in the lathe last night and drilled/tapped it to 5/16 x 36TPI in order to fit my OAL gauge. Trouble was the necks were too tight to slide the bullets in and out.

I collapsed the shoulder of my first test piece of brass trying to tap a bullet in. The second piece I ended up boring out some with a Dremel until the bullet slid in and out. I'm still not happy with it. I was thinking about cutting a small notch in my third piece with a Dremel cutting wheel in order to facilitate the bullet sliding easily.

You guys aren't just using fireformed brass for your modified OAL cases are you? I was thinking of that but figured the shoulders wouldn't be a match for the brass that I'd be loading.

I was able to get some relatively consistent measurements with the piece that I bored out with the Dremel. I'm just not overly confident in how much pressure I'm putting on the OAL rod when I tap it forward to push the bullet into the lands. I used a few different projectiles and have been getting OAL measurements within a 10-15 thou window. I guess I was hoping for something a bit more refined than that.

If the measurement that I'm getting are accurate, it would tell me that my most accurate seat depth group was .009-.019" jump.

Thanks,
Kevin

 

[CBH Australia]

I made mine from a once fired case.

The Hornady ones that I bought are not tight in the neck in anyway.

Not sure how critical the sizing or potential neck bump would matter.

If you had a bushing die you could remove the bushing.

There will be reloaders here who knew much more technical and critical dimension stuff.

 

[Deputy819]

You guys aren't just using fireformed brass for your modified OAL cases are you?

Yessir

If you had a bushing die you could remove the bushing.

^^^^This^^^^

 

[Evilsports]

Good to know, I suppose it's all relative anyhow. I'll grab some fired brass and make a few more tomorrow.

 

[Bob Wright]

I have only encountered neck collars (donuts) when extreme forming/re-sizing, or once on many reloads of same few cases. Our solution was align-boring to .005 over bullet diameter. We now carefully re-size neck with collet dies!

Wildcats and many of the AI family are known to experience it. I had wild pressure issues until I discovered it. Seating below it, it's a problem. Seating above, it's not a big problem.

 

[GRG]

I also found that the factory modified cases were to loose and the bullet would move when extracting the case or pushing it out from the muzzle end with a rod. I also made my own on the lathe then and they were to tight so slit the neck with a thin dremel cut off blade. Just split one side as f you make a slit on 2 sides it will be to loose. Should work for you then.

The other thing you can do is put just a small drop of super glue in the neck of the modified case you bought. Let it dry then slide the bullet in and out and see if it is now tight enough. If a little to tight just barely nick it with a small half round needle file.

Both ways will get you what you want.

 

[Evilsports]

Now we're talking. Made a handful of modified shells from some fired brass and took a wide sample. Four different cases, four different VLD's, two tests apiece. Great to see consistency!

 

[Evilsports]

Less the comparator my BTO is 2.729".

The grouping node that I figured was .012" jammed based on my lousy data is actually .015" off the lands. This makes me feel a lot better!

I'll take my friendliest charge weight of 58.6gr and maybe play around at .010" and .005" jump this weekend. See if it's much different.

 

[CBH Australia]

What a good looking case design, looks great to me

Good to see it sorted.

 

[SSgt G Cody]

C -"It's just going to be a little more accurate as the distance increases." Are you kidding? In what world? Distance does NOT increase accuracy! Wind, gravity, friction, and orbital effect all place more and more influence on bullet path with time and distance! Ask any long-distance sniper or shooter!

 

[Deputy819]

I'll take my friendliest charge weight of 58.6gr and maybe play around at .010" and .005" jump this weekend.

I'll bet you find a winner here. Let us know….

 

[CBH Australia]

C -"It's just going to be a little more accurate as the distance increases." Are you kidding? In what world? Distance does NOT increase accuracy! Wind, gravity, friction, and orbital effect all place more and more influence on bullet path with time and distance! Ask any long-distance sniper or shooter!

Maybe it's poorly worded or there is some misinterpretation..

I was trying to convey that having an accurate rifle is an advantage. Those external forces you listed will affect the bullet flight. Any degree of innaccuracy. In effect the group size will inevitably increase at longer ranges.

A given group size will grow as the distance increases.

I'm hoping to decrease my group size through better loads and shooting technique to increase accuracy.

You may be familiar with the term "Aim small mis Small"

That was my objective.

 

[Evilsports]

I'll bet you find a winner here. Let us know….

Loaded up some rounds at 58.6gr

Going to shoot:

6 @ .015 jump
6 @ .010 jump
6 @ 0.05 jump
3 @ lands

I likely won't make it to the range before Saturday morning so I'll have to keep myself busy with the less rewarding, but still cathartic brass prep chores. There's just something about squeezing 60 primers into cases, or trimming/deburring brass that is satisfying in and of itself. It's kind of like that satisfaction of turning a couple totes of deer meat into a years worth of packaged sausage, just on a smaller scale.