For those that have seen/done it, what does it look like on paper as you increase velocity and start to stabilize a bullet that was not stable? I'm pushing a 75 A-max in a 1-9" .223 and not getting key holes but groups are huge. As I step up charges they are getting smaller. Primers are getting flat but no stickiness in the bolt lift so I will lean on them a little more. Kinda wondering if punching to AI will give me the added velocity to get it there. I'd like to hear thoughts from those that have had success pushing a bullet in a slow twist into stabilization.

9T 223 should be fine with the 75 A max......

Tweak load.....change primer....seating depth

Burning Varget ?

This was not my experience in a 1/9 Savage using 75 AMAX. Some 1/9s will stabilize and some won't. Luck of the draw.

It's a toss up with the 1-9" twist. My other 1-9" loves them (so I have a bunch) but this one doesn't look like it'll go.

How would tweaking the load, primer change and seating depth affect bullet stabilization?

H335

You said 'not keyholeing' but 'large groups'

I ran 75 gr A's in a factory 9T Savage barrel with no probs

Higbean,

Stabilization is affected far more by elevation and temperature than velocity in a given twist. The 75 A-Max is right on the bubble in a 1-9 twist, so will stabilize and shoot decently in the right environmental conditions, if pushed hard enough, but not if things aren't just right. And even if it stabilizes the BC will be lower.

It's far better to use a slightly shorter (lighter) bullet that will fully stabilize in your conditions than to try to make a marginally stabilized bullet work. Either that, or use a faster rifling twist.

Thanks John. I will be playing with the Hornady 75 bthp but I want to do a little more experimenting with the A-Max. What have you seen on paper through the years when bullets go from unstable to stable?

My fast twist rifles, seem to ALL like the 75 BTHP better for accuracy than the 75 A Max..., the overlooked 80 grain A Max is also liked better by those barrels than the 75 grain version also...

I get it. I'm asking a different question though.

Maybe this is a better way of wording it.

When a bullet stabilizes, does it go from unstable to stable in a matter of 10fps? 100fps? 200fps? I imagine there are a ton of variables, but I want to know what you guys have seen happen.

Not asking about other bullets. Not asking for advise on loads. I'm just curious about it and would like to know.

When bullets are totally unstable they land sideways. When a little more stable the holes are oblong instead of round. When a little more stable the holes are round, but groups are big. When a little more stable, a 5-shot group may have three in a reasonably good group, but there'll be a couple of fliers, in any direction. After that, groups will start to become consistent and smaller.

Exactly what I was looking for. Thanks again John.