I loaded some 75 gn. A-Max 223, and it is tumbling when hitting the target. I used 23 grains of varget thinking that was plenty of velocity, but now I'm not so sure. My OAL is .010 of the rifling. Could it b to much powder?
bullet tumble
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Re: bullet tumble
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: snp81076</div><div class="ubbcode-body">I loaded some 75 gn. A-Max 223, and it is tumbling when hitting the target. I used 23 grains of varget thinking that was plenty of velocity, but now I'm not so sure. My OAL is .010 of the rifling. Could it b to much powder? </div></div>
No
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: snp81076</div><div class="ubbcode-body">I loaded some 75 gn. A-Max 223, and it is tumbling when hitting the target. I used 23 grains of varget thinking that was plenty of velocity, but now I'm not so sure. My OAL is .010 of the rifling. Could it b to much powder? </div></div>
No
Re: bullet tumble
Between 22.5 to 25.0 grains of Varget is what my reloading book states, for a 75gr projectile in .223Rem.
To stabilise that you would need a 1 in 8" twist or faster.
Not sure what barrel you have, but if its a remington, they tend to come with 1 in 9" twist on a .223, which is not adequate for a 75gr projectile.
Generally 70gr is the max you would push out of a 1:9" twist, maybe 73gr if your pushing the boundaries but even then a faster twist barrel would be a better option.
It may or may not be a stability issue, but just saying, check your twist rate and if its not good for the heavies go to something lower. If it happens on factory loads with light projectiles, get your rifle looked at by a smith.
Between 22.5 to 25.0 grains of Varget is what my reloading book states, for a 75gr projectile in .223Rem.
To stabilise that you would need a 1 in 8" twist or faster.
Not sure what barrel you have, but if its a remington, they tend to come with 1 in 9" twist on a .223, which is not adequate for a 75gr projectile.
Generally 70gr is the max you would push out of a 1:9" twist, maybe 73gr if your pushing the boundaries but even then a faster twist barrel would be a better option.
It may or may not be a stability issue, but just saying, check your twist rate and if its not good for the heavies go to something lower. If it happens on factory loads with light projectiles, get your rifle looked at by a smith.
Re: bullet tumble
Use the enclosed link to JBM's stability calculator to give you an idea.
JBM Stability Calculator
If its a 1:9 like the standard Rem then 69gr SMK's are your best bet.
Use the enclosed link to JBM's stability calculator to give you an idea.
JBM Stability Calculator
If its a 1:9 like the standard Rem then 69gr SMK's are your best bet.
Re: bullet tumble
Depends on altitude and temp amongst others too.
I have 2 9tw 223's and both run the 75 Amax like a champ at 1000' ASL and 65F+
At 40F and 1000 ASL I'm lucky to hit anything past 50yd.
Try switching to the 75 BTHP by Hornady, it has a very good BC and has a much shorter OAL (specifically the nose due to OTM vs. a polymer tip) than the 75 Amax
ETA: No joy on the 75 BTHP's is going to push you back to the 68 Hornady or 69 SMK. The 68 Hornady is the same shape as the 75, it just has a lighter core weight.
Depends on altitude and temp amongst others too.
I have 2 9tw 223's and both run the 75 Amax like a champ at 1000' ASL and 65F+
At 40F and 1000 ASL I'm lucky to hit anything past 50yd.
Try switching to the 75 BTHP by Hornady, it has a very good BC and has a much shorter OAL (specifically the nose due to OTM vs. a polymer tip) than the 75 Amax
ETA: No joy on the 75 BTHP's is going to push you back to the 68 Hornady or 69 SMK. The 68 Hornady is the same shape as the 75, it just has a lighter core weight.
Re: bullet tumble
I'm not going to add anything else to what's been mentioned above. Just read that and pay attention.
Good luck.
I'm not going to add anything else to what's been mentioned above. Just read that and pay attention.
Good luck.
Re: bullet tumble
I am using a 26" remington 700 with 1 in 12" twist. My next buy will b a chrono.
I am using a 26" remington 700 with 1 in 12" twist. My next buy will b a chrono.
Re: bullet tumble
Too slow a twist for the 70 grainers. Use the 55 as mentioned and you'll be fine. Otherwise, rebarrel with a 1-7.5 or 1-8 inch twist if you want the heavy heads.
Too slow a twist for the 70 grainers. Use the 55 as mentioned and you'll be fine. Otherwise, rebarrel with a 1-7.5 or 1-8 inch twist if you want the heavy heads.
Re: bullet tumble
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: former naval person</div><div class="ubbcode-body">Too slow a twist for the 70 grainers. Use the 55 as mentioned and you'll be fine. Otherwise, rebarrel with a 1-7.5 or 1-8 inch twist if you want the heavy heads. </div></div>
That's it in a nutshell.....
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: former naval person</div><div class="ubbcode-body">Too slow a twist for the 70 grainers. Use the 55 as mentioned and you'll be fine. Otherwise, rebarrel with a 1-7.5 or 1-8 inch twist if you want the heavy heads. </div></div>
That's it in a nutshell.....
Re: bullet tumble
On aside, the 53 TSX's won't stabilize well in that 1:12 either...too long a bearing surface.
It's the length of the bullet, and not so much the weight, that's twist dependent. It just so happens heavier bullets are generally long, and thus the general misconception.
Drop to the 55's in that rifle and rock on, as suggested....
On aside, the 53 TSX's won't stabilize well in that 1:12 either...too long a bearing surface.
It's the length of the bullet, and not so much the weight, that's twist dependent. It just so happens heavier bullets are generally long, and thus the general misconception.
Drop to the 55's in that rifle and rock on, as suggested....
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