TWIST (from a riflemans perspective)
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- เผยแพร่เมื่อ 25 พ.ย. 2024
- Lots to say, only 20 odd minutes to say it, so yes it was a quick video, lol, hope it helps.
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I’m not understanding how mark & sam don’t have half a million subscribers. Even for the non elr guys everything in these videos is applicable. Thanks guys, keep the great videos coming.
Glad you liked the video and well TH-cam wont let happen anytime soon, lol, cheers
Honestly they just have to much content for the average viewer or shooter for that matter. IIRC most viewers watch about 3 mins of a video
I think ita not because their videos arent good but because most people are more attracted to entertainment than instruction
As Taylor and Nicolò suggest, attention spans are forever decreasing as over stimulation forever increases; there's a relationship there.... The very best channels on TH-cam are the ones our algorithmic overlords detest. In any event, I recently found this channel, and it's in my top three now. It's so gratifying to find these gems!
@@taylorbokshowan5713 how odd.. Ive watched many of the vids multiple times.
Never owned a fire arm, maybe never will, but absolutely enjoy these videos.
The engineering, science and trial and error that goes in to great shooting and making components,
be it for ELR or otherwise, is just insane. Genuinely educational, love it. It's top stuff, thank you.
Thanks Andrew, glad you enjoy, Cheers and all the best.
That's really good to read mate ,ayne you should give it a go
Thank you for the outstanding presentation. As an aviator, I can attest that all you have said is 100% correct. After all, it is aerodynamics, which is a subset of physics.
Thanks Man, Cheers
I'm not sure who would give this a thumbs down or why ? There's no misinformation here .
Thanks for doing your thang your way guys .
Yeh, who knows, takes all types, lol, cheers and all the best.
Only a moron would give Mark and Sam a thumbs down.. Guys let no one ever discourage you in any way. And yes there should be a million followers!
Sometimes people did that by mistake, especially from cell phones. I did it once or twice. Meant to like but pushed dislike instead.
@@BlueTJay l
These last few videos were just what I was looking for when I started reloading. Now that they are out there I can recommend them to friends. This is an awesome resource you guys are building and I thank you for it. Keep up the great work!
Thanks Man, Cheers
Beautifully explained Mark.
Thanks Man, Cheers
Again, thanks for your pure intusiastic style.
I'm not in for constant power wording this hobby/sport.
In the most of these contents there is a large hidden john Wayne in every sentence.
You stay technical and friendly. Same about your wife. My opinion:
That sends a strong massage into the world, that is needed for this sport community.
Greats again from Bavaria.
Sorry for my bad english
thanks again Man, Cheers
Your series of technical/theory/science videos are always very interesting. I'm extremely impressed with your knowledge and delivery. It's impressive that you can take a somewhat complicated concept and explain it in a way the layman can understand. 👍👍👍
Thanks Man, glad you liked, Cheers
Thanks Mark. Not sure how I missed this one. The topic is one I’ve been interested in for a long time, and you explained it better than most.
Cheers Man, thanks
I can’t tell you how many of your videos I have referred too and recommend people to watch. Mechanical minds think a like. Great video.
Cheers Joseph, thanks
Best explanation possible..ithink the gyroscopic top is great illustration too! Thank you!
Cheers Man, thanks
Thanks Mark,,I injoy all of yours and Sam's videos,,,
Thanks Bronte
20:30 - I remember hearing someone *adamant* they had a setup that would shoot 1/4 inch at 100yds, 2-3 inch at 200yds, 1 inch at 300 yds !! Yep, they put it down to over-stabilisation. Seems like it could be a real thing. Thanks for your video, well presented.
Thanks Man, Cheers
I have a theory that it is a real possibility with lightweight barrels with lots of whip.....just like us spinning that top, whips the bullet out a little unstable and then becomes stable in short order??? Thoughts??
@@lovetoflylovetofly3843 no, not a likely cause of stability issues, can cause accuracy issues, but that is a different conversation, Cheers
Thanks Mark,
You and Sam have bin helpful. I often consider your point of view to my benefit. At 63 years old with a lifetime of shooting and reloading under my belt. Good information can be hard to find thanks again.
Thanks man, Cheers
I recommend Bryan Litz's book "Modern Advancements in Long Range Shooting", he goes in great detail on rifles, sights, bullet design, construction, rifling twist, internal ballistics, and external ballistics. Mr. Litz does math until he's blue in the face, and then he goes out in the real world with real projectiles in various ways to test the theories. He, unfortunately, doesn't go into extreme and ultra long range shooting. It's an amazing wealth of knowledge regardless, as are you, Mark. I'd love to get your opinion on Litz's work.
Well, Brian has and does great work, lots of research, lots of reading and puts real effort into his job as a ballistician, he is a very valued member of our community. As for me, I come from a different perspective, I use some of that, but I am probably a little more where the rubber meets the road, not always so easy to share all my logic, but as said I use a balance of everything, including some of Brian's work. So in plain speak, he is more the engineer and I more the mechanic, I quiet often disagree with engineers, that also sometimes happens with this, but I always listen, Cheers
Great explanation, useful information for all really puts things in perspective.... Especially when it's spinning at 200-300,000 rpms.
Cheers Paul
The early M16's had a slow twist. Because they WANTED the bullet to stop spinning and start tumbling end over end. This is like a punter in football who is said to "turn it over" because if he can impart a bit of spin on the ball as it is going upward, it will go further. Then the ball will stop spinning and start tumbling end over end, and take longer to come back down. This was done in the M16 to cause the bullet to tumble and do more damage to make up for the smaller bullet. However the Geneva Convention stepped in and made them stop doing it as a violation of something akin to using a soft nose bullet rather than a full metal jacket.
Not sure on that one, but OK, thanks for the comment, Cheers
Ummmm... no.
Love this kind of explanation, always interested in learning. 👍 thanks guys, stay safe
Cheers Pieter, thanks
Brilliant presentation, Sir! Wishing you and your dear ones a Happy Christmas.
👍👍🤠
If you haven't, have a look at Jim Boatright's paper on hyper-stabilization by way of "over spinning" of monolithic bullets, and the application at the trans-sonic threshold.
Cheers
Nailed that description with the spinning top. Now we just need to come up with a ratio of length, diameter, needed spin, fps. Kind of like bc that way it can be applied to any weight of pay load.
Cheers
Thank you Mark very well explained Steve.
Cheers Steve, thanks
Very good, been shooting for 60 years very good job
Cheers Man, thanks
Wow - that orbit theory is pretty interesting. I would imagine that if there is ANY imbalance through the rotary axis - that could be very possible. I bet there's some truth to that.
Another great video that had me glued to the monitor.
Cheers Mike, glad you liked, Thanks
Great informational video, explained it well, thanks for posting 👍
Thanks Man
Brilliant, thanks! So, to summarize... It's how fast the bullet spins per-time, not how many times it spins per-distance. The longer bullet, not necessarily the heavier bullet needs more RPM.
So, if you had total control over velocity, you could overcome a lack of barrel twist with higher velocity? Such as, and arbitrarily, a 1/9 barrel twist at 2,450fps yeilds the same RPM as a 1/10.5 twist at 2,850fps ... ?So you don't need as much barrel twist in your SAUM as you need in your Creedmoor to stabilize the same length of bullet, for example, I realize this is maybe an over-generalization.
I've heard 100 men fumble over how to explain what bullets do on their descent, when you explained gyroscopic yaw, it made perfect sense.
Thanks again!
Thanks Tom, and well yes that is the basics of it, of course we don't have much choice is speed, so not really an option, but yes that is the principle of the deal, glad you liked, Cheers
Thanks , as always, for your reply! With all the powders to choose from, I understand that, if you load to capacity you could get a few hundred fps difference from the faster to slower burning powders, depending on barrel length, of course.
But, more what I'm saying is, for instance, if Barnes says I need a 1/9 twist .308 Win. to stabilize a 200 grain bullet, then a 1/10 twist Win Mag or RUM is probably plenty ... ?
Thanks again!
@@triptideom yes, probably, Cheers
Thanks!
@@triptideom I think you might consider the sectional density of the bullet which can be an indicator of the rate of twist needed to stabilize that bullet. Bullets with higher sectional density are usually longer bullets requiring a faster twist rate. It doesn't matter how fast the bullet is traveling it will make 1 complete rotation every complete twist of the rifling. I think most rifle manufactures twist the barrel for the bullets and loads used by that rifle most often by the common customer.
I had an interesting experience with my 7mm 08. It would shoot heavier bullets best, 140 gr and 150 gr even better. 120 gr bullets not so well. But also, I bought some high performance fast 140 gr with a long tapered ogive and they did not shoot as well. I can't really say whether it was a bullet jump thing or the fact that the heavier bullets with a more round ogive had more contact with the rifling. On the other hand have a 308 and it shoots 150 gr to 180 pretty well, I have had groups in the range of half inch to one inch with different brands, different velocities, different weights, all copper, lead tipped, etc. (Don't expect me to shoot better than a half inch, I'm not that good). I realize there are many variables, I have heard that even boat tails make a difference, powder loads etc. As a commoner, I just experiment and go with what works for me. Many thanks for the great videos!
Hell yes, we all be commoners, and the best part is working it out, also keep in mind, most folks that claim a 1/4" group are talking there best ever, but you and I know, it is so much more about our average group... Cheers
Smart guy..Covered the topic well.
Cheers
@@markandsamafterwork Appreciate both your efforts .I envisage lots of time and effort has gone I to this.
Yes a bit, glad you liked, Cheers
I think that the "orbit" aspect of the bullet spin comes from friction between the surface of the bullet and the air. Air grabs the surface and creates that orbital flight. This would also get into the depth of groove cuts from the rifling. As you say there is lots to learn about....all fun.
Great video by the way. And for those in the US...think of throwing a football with the "spiral". Not 180000 rpm but it gives you the idea. hahaha
Thanks Hans, glad you liked, Cheers
Great info and presentation! Thank you!
Thanks Scott, Cheers
I'm disappointed that The Curiosity Show didn't cover this when I was a kid.
Lol, bastards, cheers
it was probaly hard to demonstrate with a paper plate arubber band and two paddle pop sticks
Excellent explanation and great content as always. It is amazing how much science is involved in firearms and projectiles. Another interesting topic would be the various types of rifling and which seems best for ELR and barrel life.
Cheers
Thanks for the video. Great information.
Cheers
Great information thanks Mark. Currently trying to find the best weight/length bullets for my 1 in 8 twist 223. 77 grain (Berger) bullets = a single ragged hole, 57 grain bullets = 1/4 inch, 55 and 53 grain bullets = 3/4 inch. Was hoping to be able to get under 1/4 inch from lighter bullets as well, but looking at the data so far, I think its only going to be 60 grains and above for any real accuracy. Can't always have your cake and be able to eat it too!!
Yep, lol, Cheers
You should try barrels with 1:9", 1:10", or even 1:12" twist with the lower weight bullets for your 223 Remington.
I use a 1:14" twist barrel that is 31" long for my 220 Swift. Velocity is just over 4200 fps.
You did a great job explaining it, I kind of wondered about overspend, , thanks for sharing
Cheers
Is it also possible for too much twist to cause more of a spin drift affect???? Just something that I've wondered about...
Not a concern in that way, Cheers
Well worth watching
Thanks Joe, Cheers
The weight-speed(power)-twist-ratio is where a lot of magic is happening.
This is why i like this hobby.
Finding out, what's going on.
...and a lot of time the problem is 2inches behind the scope 🧐🤔😀
Cheers
Mark, I suspect the 'orbit' you speak of may be due to the center of mass of the bullet is slightly off the center axis of the bullet. Also in such a case as the bullet travels down the bore, it will impart a force radially on the barrel and cause the barrel to vibrate. All very interesting. An advancing twist make sense to me for two reasons. 1) the initial
acceleration is less of an impulse: so you are not "spinning your wheels so to speak" starting a bullet with no rotational velocity to rotate instantly,... 2) the energy bandwidth that is developed as the bullet proceeds down the bore is spread out and less likely to impart energy at a barrel resonance.
Keep in mind, set twist acts the same as you are describing, because both velocity and rpm are starting at zero and accelerating as they go down the barrel, Cheers
@@markandsamafterwork of course.
Cheers
This was a great video. Thanks.
Cheers Man, Thanks
@MarkandSam AfterWork
Now that you've covered twist and centrifugal force, (maybe I've missed the video) how about talking about adjustments for "spin drift". Thanks for any replies or future video.
Well, not sure it's worth a video, just do the maths, or in most cases, just use the right app, and just like all settings, it is only the first shot, once you see your impact, you adjust from there. Also, in any normal sense, by the time spin drift really matters, you are really not in the first shot zone anyway, but we'll see, Cheers
Thanks Mark. Had to watch the speed of my 220 swift. I get gray puffs at about 3850 FPS. ( cheap bulk 55grn bullets) I could push 50 grn solids to 4100 FPS
Yes that's the deal, glad you liked the video, Cheers
The thumbs down shows that no matter how excellent something is, there is always some asshole that will complain.
Yup, lol, cheers
I have seen the yah watching slow motion tank rounds. I was led to believe that the projectile not only has a center of gravity but also a center of pressure. Since the force of the projectile passing through the air is affected by that air 80 times more than the force of gravity the projectile may yah because the center of pressure is not identical all the way around the projectile. So rpm would certainly have an affect.
Cheers
Mark, did you machine that top just for this video? It's cool
Yep, Cheers
MarkandSam AfterWork I want one... You making extra?
More serious... I've watched your channel for a LONG time and have learned lots... you and Sam have been great motivators... thanks for all you do
@@bullast2046 Lol, bit under the pump ATM, but thanks and glad you like what we do, and glad to help motivate, Cheers and all our best.
I’m surprised he didn’t mention the Greenhill formula for determining the twist rate for a particular bullet.
Cheers
Great info and discussion - but what about the variance in barrel length with the same twist (guess it is more stable with increased length given the same twist ?? ) - btw - thx for sharing :)
Stability is gained through RPM, if more speed with more length with same twist then more RPM, so as always, all in the details, Cheers
If a longer barrel gives you a higher velocity, the bullet will spin faster.
Very well explained !
Thanks Arthur, Cheers
Kind of sounds to me like Ballistic Coefficient and needed spin are related.
Just follow the manufactures recommendations, you'll be fine, cheers
Very informal video! Thank you Mark & Sam. I shoot a .300 Rum Reminder Sendero SFII. Recently ordered a Krieger barrel in varmint contour and the the barrel TR is 1:10" . I want to start getting into 1500 - 2000 yrs shooting what weight bullet do you recommend? I been purchasing Noslers 210 gr. Match in 690 BC. Is this twist rate suitable for this bullet at this range?
Hi, I don t make recommendations, those should be fine, FYI I use the 230grn berger in my 1:10 300wm for my ELR stuff, Cheers
Great video....need couple Panadol after that one & a lie down!!
Lol, Thanks glad you liked, Cheers
Hi Mark. Great video. I have a Ruger America 30-06 1:10 twist. The bullet I shoot is the Hornady ELD Match. Box says 1:12 twist. Will this bullet be unstable in my 30-06
Hi Hilton, no works the other way around, the lower the number the faster the twist, so that will be fine, if you had a 1:13 twist barrel it would be an issue, Cheers
What app do yall use to measure distance to target I've seen on some of yalls vids? The one u click on then go to shooting position and click again to show distance?
Measuring tape
@@markandsamafterwork thank u sir
So how long till we see you running smooth bore fin stabilised rounds guys 🤣
Lol, Cheers
👍 video sir.
Cheers
good job.
thanks.
Cheers
Well done
Cheers
That was very interesting.
Cheers
@@markandsamafterwork ... and thank you too for making this video, it was educational and enjoyable.
Awesome, glad you like, Cheers
If I were a betting man I'd bet Mark machined that top...
yep, Cheers
338 RUM как хороший калибор
Cheers
K. maind u god wlorlotrwltr .hahahahahahahaha god✌
I am sure that said something, but I have no idea, hope you liked, Cheers