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> Twist rate effect on accuracy
Twist rate effect on accuracy
@ 08:55 am (GMT) |
Scott StruifAt 51:45, Hornady claim that faster twist rate than needed for bullet stability enhances inaccuracy:https://youtu.be/oOZEv7OZicU |
Replies
@ 06:42 pm (GMT) |
VinceRe: Twist rate effect on accuracyHi Scott,It makes sense with the explanation, use enough twist to stabilise what you shoot and maybe a little more for margin of error or a change in projectile, after that why go for a tighter twist? I've think I read either somewhere on this site or in one of Nathan's books that the Berger VLD used to be an effective longer range projectile until people started over spinning it in fast twist barrels and it came apart so they strengthened the walls and its long range terminal performance turned to poo. The Hornady ballistician seems to be very good at dumbing down explanations, I've been enjoying the podcast series so far despite the marketing influence. He was also in a Vortex podcast on terminal ballistics which was interesting although if I was listening accurately he stated that heart shots cause death more quickly than lung shots which hasn't been my experience. He was also pushing penetration being the key to performance, reading between the lines I assume he meant that over penetration was as much of an issue as under penetration although that wasn't necessarily how it came across. Given that he was also pushing the new Hornady monolithic offering maybe this wasn't accidental...... Cheers Vince |
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@ 08:52 pm (GMT) |
Scott StruifRe: Twist rate effect on accuracyHi Vince.In one of the 2 recent Hornady podcasts about external ballistics, the ballastician gave a preview of the upcoming talk on terminal ballistics. He said match bullets used for hunting work by tumbling inside the animal, thereby coming apart. He said that the faster you spin them, the more likely they won’t tumble in the animal, due to gyroscopic stability. Nathan’s field research has confirmed that. When a match bullet upsets by yawing in the animal, the ogive bends and gives way, causing the core to separate from the jacket into a thousand pieces. That’s why Nathan anneals bullets - to get them to break apart more readily. The problem Nathan and others have observed with Berger bullets penciling through game could be caused by Berger recommending fast twist rates. Maybe they also thickened the jackets on them to compensate for the faster recommended twist. In any event, Nathan’s advice regarding twist is consistent with what the Hornady guy said. In his (free) 308 hack rifle video, he said 11 or 12 twist is fine for a 308 or 30-06, even with heavy 220 gr. bullets. The negative effect on accuracy of a faster-than-necessary twist hadn’t occurred to me. If I were having a custom barrel made, I’d think twice about a faster-than-normal twist rate. You’re right about having to read between the lines on those Hornady podcasts! They’re produced by their marketing department, so you can’t really trust anything they say. [b] |
@ 07:06 am (GMT) |
Nathan FosterRe: Twist rate effect on accuracyVince, I spoke about it in the Cartridges book and also in a lecture here:https://www.youtube.com/watch?v=Ikc_EjSD_S8 |
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@ 10:32 am (GMT) |
Nathan FosterRe: Twist rate effect on accuracyAlso, yes, heart shots are slower killing than lung shots. To say otherwise is to advertise a lack of field experience which should start to raise alarm bells among the discerning. This also comes from the company who said that they felt that the bullet technology employed by DRT was a bad idea and that such bullets would not even penetrate the hide of a coyote. This after I sent them the results of barrier tests with the DRT. My mistake, the report was sent to them in hard copy with color photos rather than via twitter or something with a click if you like button. I had also forgotten to wear my tactical beard when I performed that test.Podcasts and such are all well and good, but we are beginning to lose practical skills and field experience. Wake up guys. |
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@ 11:45 am (GMT) |
Scott StruifRe: Twist rate effect on accuracyThe Hornady guys are typical, US hunters, indoctrinated at a young age with the myth of the behind-the-shoulder shot - the heart-shot being the epitome. The proverbial “vitals.” That’s all well and good if you’re hunting in Nebraska, where tracking dead-run game for several hundred yards isn’t a problem.I’m looking forward to their podcast on terminal ballistics . . . not because I expect to learn anything. I think it’s going to be hilarious when they tout the CX bullet for long range hunting. I’m sure it will be entertaining to hear about mushrooms, pass-throughs, etc. Not once so far have they suggested dual-loading the CX for short range shots. All they’ve done so far is cast doubt on the efficacy of the ELD-X. |
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@ 06:11 pm (GMT) |
VinceRe: Twist rate effect on accuracyI went back and checked to make sure I didn't misinterprethttps://www.youtube.com/watch?v=EPi1pxtesmI&ab_channel=VortexNationPodcast at about 9.20, be interesting to see if he corrects this in Hornady's own podcast on terminal ballistics. No need to worry Nathan, I'm a born sceptic, I used this as an example of don't believe everything you hear. I found the internal and external ballistics podcasts interesting just in terms of understanding in laymans terms all the different elements at work on a projectile and to what extent they are likely to be relevant, most of the information is unlikely to ever be a significant factor in my hunting shots as they are mostly close range but it's good to have a basic level of knowledge anyway. While the info I have applied from you through the book series and from questions on this forum has proved true to date (and will continue to be no doubt), I prefer to verify as much as possible myself, hope you aren't offended by this, it's just the way I'm built. I still remember the first deer I shot with an ELDM, I had a mate standing by with a 308 and a proven soft point just in case things went south! They didn't of course but trust is earned incrementally over time, particularly when an animal could suffer as a result. In the mean time happy listening, like you Scott I will tune in and try to separate the fact from the myth and marketing! Cheers Vince |
@ 10:10 pm (GMT) |
Magnus HanssonRe: Twist rate effect on accuracyQuote: Also, yes, heart shots are slower killing than lung shots. To say otherwise is to advertise a lack of field experience which should start to raise alarm bells among the discerning. This also comes from the company who said that they felt that the bullet technology employed by DRT was a bad idea and that such bullets would not even penetrate the hide of a coyote. This after I sent them the results of barrier tests with the DRT. My mistake, the report was sent to them in hard copy with color photos rather than via twitter or something with a click if you like button. I had also forgotten to wear my tactical beard when I performed that test.
Podcasts and such are all well and good, but we are beginning to lose practical skills and field experience. Wake up guys. Think about all the money that the whole industry have turned around selling 6,5 creed to half the US ..when we Swedes go like “we had that already in 1891”. They are so skilled sellers they could probably sell sand in Sahara. |
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