AccuBond failure.

[seymour fish]

Art Alphin gives a concise explanation of this phenomenon in 'Any Shot You Want'. To paraphrase, for a given SD and MV, too slow a twist produces unpredictable path in tissue, wheras too fast a twist produces riveting of projectile. Though his discussion concerned solids, it should serve as a general guideline. He also discusses a desirable percentage of bullet expansion using non-solids. The accubond version of the ballistic tip is still an iteration of the original varmint bullet, thicker jacket notwithstanding. Thus designed from the getgo to overexpand, with tweaks to lessen this effect. This theoretically causes rapid loss of rpm's in the tissue and thus a tendency to wander off path. You likely have a situation where inadequate twist meets relative overexpansion. On elk you might desire SD above .250 and closer to .3, thus must lean toward a faster twist, and faster yet if a long high BC design. The nosler partition, as previously suggested, might solve your problem in short order, by getting you back inside the envelope. It will kill and elk you hit in the vitals. You might want to confirm the twist rate in that barrel. Seymour

 

[wboggs]

This confirms what we learned from experience. Best twist for a .458 at 2400 is 1-12 or 1-14.
We tested a .460 Wby with 1-16 and a 500 gr at 2650 fps. Penetration was less than a 500 gr loaded to 2400 in a 1-12 .450 Rigby. Also, the Wby penetrated less than a .416, 1-12, and 400gr at 2400.
The Nosler AB is not designed for straight line performance but for a high BC that does not fragment.
That book you quote sounds like it was written by someone with a great deal of practical experience

 

[swampshooter]

I have harvested an awful lot of game in my lifetime. Started hunting at 9 years of age and I'm 68 now. I have never had a bullet go in 2 or 3 inches into only soft tissue and make a 90 degree abrupt turn. I've had them ricochet off of bone and totally change direction, but not frequently. I believe that there must be a lack of stability problem involved here.

 

[rwk]

Reading a old Handloader mag. they state spitzer type bullet sometimes make 90 degree turns.

 

[swampshooter]

I'm aware of 90* turns occurring with FMJ spritzers and even soft point when bone is encountered. My rifle, my loads, we have extreme deviation three times in a row. That doesn't qualify as " occasional " to me. I'm going to make a change before I either lose my next elk or wind up with a gut shot mess. Different bullet or a different caliber altogether. I have other rifles that I can use.

 

[BigDMT]

I'm aware of 90* turns occurring with FMJ spritzers and even soft point when bone is encountered. My rifle, my loads, we have extreme deviation three times in a row. That doesn't qualify as " occasional " to me. I'm going to make a change before I either lose my next elk or wind up with a gut shot mess. Different bullet or a different caliber altogether. I have other rifles that I can use.

I'm telling you... Start using Berger hunting VLDs and never look back...

 

[AckleymanII]

I shot 95g partitions in a 6 Rem for many years. It is amazing to see the directions that these bullets take upon expansion.
In additions, the nose will sometimes separate and you are amazed even further at how the two pieces exit in unpredictable directions.

As bullets get upset on their axis, a wondering path they take.

 

[cattlebuyer]

I have turned into a huge accubond fan, .243 to 7STW and 300 win mag, my all time favorite is the 110 gr .25 cal. I would love to be a Berger VLD guy but I just cannot get em to shoot as accurate in my guns. I wish Nosler would come out with a .22 cal accubond! For many years I was the same way on BT's , many untold whitetails without a failure, I am a stickler for bang flop shots, shoot and go get the truck, I love to watch em go down like the air was let out. I find the accubond almost as accurate as the BT as well. I have yet to experience the '90 degree turn'. . I own and shoot everything from .22 hornet and Bee to 300 win mag . my 2 cent , YMMV, very best CB

 

[BowGuy]

To each his own but I don't see your experience(s) as an Accubond failure. That same bullet has served me well. One moose, good many elk, numerous whitetail and mule deer. A good many fell in sight. Did I follow the wound channel? No. Had any bullet taken a detour along the way, would I have considered that bullet a failure? Not on your life.

It would be interesting the learn what Nosler reports back.

 

[GSPV]

Nothing, and I mean nothing, moving at velocity is going to change angles 90 degrees. Kind of violates conservation of momentum.

 

[swampshooter]

GSVP, I take it that you're calling me a liar then. I think that you're long on theory and short on experience.

 

[GSPV]

Weeeellll, it depends.

If you say that an object with mass changed vector by 90 degrees without a force acting on it, then, I'll tell you to go look for that force. Because it's there.

Something less than 90 degrees after encountering a force. You bet. 90 degrees *in total* over an arc! likely after being deflected by some force! sure.

Short on experience? Google "chicken gun". I have tons. Literally.

 

[Smalltruck]

GSPV if you get to shoot and test chicken guns for a living, I want your job...

 

[swampshooter]

Any connection between bullet stability and chicken guns would have to be a big stretch. If you don't understand how bullets can and do change directions after impact you need more actual experience and less of your misunderstood book theory. It is not at all uncommon for a bullet to change direction after impact, if you have not experienced this you have not shot very much or for very long.

 

[CJ6]

If you had recovered the bullets what did they (noses) look like ? Bent ? good mushroom ? or a sheared mushroom ?

 

[swampshooter]

They are sheared off on one side with a lop-sided mushroom.

 

[langenc]

I dont know about what a bullet does after hitting tissue only, I do know that when a bone is hit all bets are off..

My Army days were spent where animals were shot in the thigh and then doctors were allowed (required) to debried the wound. When a bone was hit, not desired, the bullet would go all gollywampus.

I suppose in bertain conditions tissue could act as bone did.

Animals were anesthetized, above but PETA still didnt like it!!

 

[swampshooter]

Yea, PETA would rather have a soldier lose his life because the Dr. didn't know how to treat his wound than allow the Dr. to train properly on a pig.

 

[CJ6]

They are sheared off on one side with a lop-sided mushroom.

I'd bet the bullet hit bone or hard cartiladge

 

[swampshooter]

I would have to say no, it hit right in the softest part of the flank, behind the ribs and in front of the hips. We probably wouldn't have known it was a hit if the bullet hadn't changed directions and penetrated the liver. I wouldn't complain but the two previous elk the bullet changed direction almost as much which turned lung shots into backstrap damaging shots. I'm a heart patient and I hunt elk for the meat, the backstraps are important to me. I don't want to continue damaging backstraps. That's three bullets that hit elk broadside and failed to penetrate to the opposite side of the animal. I think that they are borderline unstable when fired from my rifle. Rem. 700-7mm RM. and lose their stability altogether upon impact. I'm going to change bullets this year.