Progressive Depth Rifling: the most misunderstood feature of Civil War-era rifles
ฝัง
- เผยแพร่เมื่อ 12 พ.ย. 2023
- Almost all Civil War era rifle-muskets had a special form of rifling in their barrels, with grooves that were quite deep at the breech but got gradually shallower towards the muzzle. For some reason, this made them more accurate. People have been asking why ever since.
Progressive depth rifling is poorly understood and the source of much confusion and argument. Is it absolutely necessary? No. But does it make a military rifle shoot better? Yes.
The man really goes the extra mile in his presentation. Really gives the air of a distinguished end of last-century gentleman. The suit, the drink, the audio....
These antique microphones aren’t cheap.
The end of the last century wasn't that bloody long ago.
@@papercartridges6705 Hah.
Ref. the expansion of bullets (and this was with a shallow grooved muzzle loading match rifle, not a service rifle with its deeper rifling) . . . In February 1865, W.E. Metford experimented by drilling a hole into a barrel a quarter of an inch above where the base of the bullet would be when the rifle was loaded. A plug was then screwed in, in the end of which was a little point. This hole through the barrel came into one of the grooves; the screw plug was set such that it was not projecting sufficiently to cut the paper of a cylindrical bullet on loading. The rifle was then loaded and fired into damp sawdust. When examined the bullets carried a little line scored in, beginning a quarter of an inch from the base of the bullet. This showed the bullet expanded fully before it had moved any practical amount from its position in the barrel.
Progressive rate rifling is used in artillery to prevent stripping, I was unaware that Progressive depth was used also. I guess it could be called choked rifling.
Gain twist ( progressive) rifling was used in most of Colt cap and ball revolvers of that era
My immediate guess about how progressive-depth rifling was discovered was that it was an accident. That's usually how huge breakthroughs are made. I even pegged it as a manufacturing error, though I didn't suspect that it was because of trying to rifle a smoothbore.
I dont want to stomp all over your worldview because I dont even know what it is, but all those stories you hear about stuff being discovered on accident isnt true at all. At best those stories rise because it makes for a quick, nice story, and at worst it's a cover story for stealing research or equipment. Whoops! we accidently entergized the microwave equipement we acidently made on accident next to the chocolate bar I accidently had in my pocket! silly me. You dont belive this, do you?
Thank you for a very non boring video. I find this stuff to be quite fascinating. I bought a Parker Hale 2 band new in 1975, serial #3000. I know that it has progressive depth rifling but never knew what it was all about. 48 years later I finally found out. Thanks for the education!
2 dumb stories - my uncle had an M1861 Springfield he kept behind a cabinet in his house - but he passed and I don't know what happened to it. And just a couple months ago I went to buy an M1841 'Mississippi' rifle in an antique store I'd been going to for 20 years - I used to take it down and fiddle with it for years - only to find the owner had died and the store was now a CPA storefront. Moral of the stories - if you see it, get it.
I love how clinically self-aware you are about how -dull- -boring- exhilarating these videos are.
Jokes aside, though - these long, thorough, well-researched videos are my favourite type of content you produce. Thank you for taking the time to put these together!
You could argue this is objectively a boring video
The question that I have is, HOW did they accomplish the progressive depth rifling?
A cam mechanism on the rifling machine guided the blades to cut progressively deeper grooves towards the breech. It can also be done manually by adding thin shims.
@@papercartridges6705 Thanks, I'll have to think on that. I had considered using shims to achieve a varied depth, but imagine that it would result in a "stepped" groove.
My thoughts on the process were:
rifle the whole barrel to .005;
rifle the first 3/4 of the barrel to .0075;
rifle the first 1/2 of the barrel to .010;
rifle the first 1/4 of the barrel to .0125.
But this would leave .0025 "steps" between the depths. I suppose that lapping the bore could smooth the "steps" away. Or one could take more but smaller steps over increased fractions of the barrel, i.e. .001 per each 10th of the barrel length.
Interesting engineering problem...
if I recall correctly there was a video on the resident gunsmith of Colonial Williamsburg and in the rifling process they added shims of paper that compressed over time, maybe you can use that concept to prevent stepping. or simply lap the grooves using a spring loaded bit to smooth the transition between the steps
Thanks Brett! I have an Express cartridge double with Turners Patent Rifling probably made 10-12 years after this. Turner made the first half progressive depth with sloping sides, then the second half constant depth with square sides. Original ammo was paper patched. After a lot of frustration in past years I left it in the safe; now I am having a go at paper patching it.
He oversold his video and he delivered on his promise. That's a paradox, it should not have been possible! ;-)
I am so waiting for somebody to come up with a marketable skill from this.
i think a best way i get it explained is to say the bore diameter is consistent and the groove diameter gets "tighter" towards the muzzle and actually squeezes the bullet smaller at the muzzle.when i say" rifling gets shallower" it confuses people.the land height is consistent if measured from the bore. centerline.
great video thanks
Thought of the German sPzB41 when I saw this vid - the Germans got great results from 'squeezing' an A/T round.
riveting. there is so much knowledge and understanding to be gained from the past. on a past video you mentioned there are some barrel makers who will do this, if I recall correctly. very interesting subject matter.
That’s my question as well. You have mentioned that there is someone making barrels with the correct rifling for the P53 Enfield. I’ve read all four of your books and vaguely remember the name of maker is mentioned there as well. The Italian makers probably think their guns will be used for shooting blanks.
@@johndally7994 to be fair most the Italian ones probably will be primarily for blanks, maybe some patched ball for the fun of it, not for serious shooters looking for performance.
Parker-Hale of Birmingham, now long-gone, cut rifling like this into the barrel of their Model of 1861 Musketoon. Not sure if they did it with any others they replicated, though.
Did Happen to be watching this at night before I go to sleep, but I made it through.
Great material for falling asleep. I slept like a log. I'd appreciate more civil war era lullaby. Thank you, Brett, Professor of Musketry.
More serendipity in rifling from a century earlier. George Washington was well familiar with long rifles in his wilderness travels as a surveyor, and intended to use them as terror weapons at Boston. Europe had rifles, but none had the range of the Pennsylvania long rifle developed to overcome severe lead shortages in the colonies caused by mercantilism. Pennsylvania gunmakers reduced the caliber and increased the velocities by slowing the rifling twist so a ball smaller than 50 caliber would kill an elk or bison. Probably an unintended consequence, the faster velocity also doubled the range over 60-65 caliber European rifles. At Boston, 300 yard individual shots were documented as well as team firing neutralizing crew targets at 500 yards. General Howe put a bounty on capturing a rifleman with rifle and English rifles like the Ferguson largely didn’t improve in range until that happened.
Not so much the rifles as the, as you say, terrorists using them. They were well known and also well known to be largely useless on a real battlefield.
Fascinating, not boring at all
I really wish we could convince Italian gun manufacturers to adopt PDR for their Civil War repros, but I guess we're just stuck with buying originals or living with garbage accuracy.
Thanks again for another great video. May I suggest you partner with Cap and Ball on a project? You two do a great evidence based review of firearms and I think you two would be great together.
I talk with Balázs from time to time, we have very similar interests and I have been watching his videos for years! Great content.
Well. I still don't understand exactly WHY progressive rifling is a good thing, but that was a bloody good video."It works.". "why, how?", "it just does, ok?"
That was a fascinating explanation, this from someone with no practical shooting experience but a keen interest in history.
Funnily enough the standard French infantry rifles muskets used uniform depth rifling from 1857. Only the chasseur carbines and artillery musketoons retained progressive depth rifling.
Probably another example of the pragmatic French approach to the rifle for the line infantry… good to have, but nobody is expecting spectacular accuracy. After all, if you are aiming with your knuckle… your rifle probably doesn’t need the tricky expensive progressive depth rifling.
@@papercartridges6705 I read a French report stating that progressive rifling was only good with tamisier bullets with the pillar breech and no good with miniés 😆 The chasseurs carbines, aside from the 1859, all had pillars and progressive rifling and kept it even once the pillar was removed.
Thank you Brett. Well presented. Have ‘fun’ in your deployment……. May it not be ‘interesting’.
I survived! Great video as always. Love the historical references and amount of detail. Thanks!
I was actually really excited when I saw the video come up in my feed, especially after the previous one on reproduction rifles!
Never ceases to surprise me that people are excited about some history nerd droning on for 22 minutes about how deep grooves in antique muskets are.
@@papercartridges6705 you think you are the only nerd?
@@papercartridges6705 Honestly I’ll listen to you drone on about any topic like this, it’s really fantastic! I’ve really enjoyed the few times I’ve been able to stop by your shop and talk a few hours!
The French rebored their muskets in order to use heavier bullets, because French bullets were very light compared to the British bullets, so they considered them to be underpowered. The French bullet weighed only 25.6g compared to 31.3g for the English bullet, which gave 1/3 additional penetration at the distance of 270 m. Swedish, Prussian and Russian bullets fall between these two extremes in terms of weight and penetration.
Stayed awake for the full 23 minutes Brett.........very interesting and a warning to me when Pedersoli eventually produce their Baker Rifle - shallow rifle grooves.................😩😩
Well I’m a little disappointed that the knowledge I’ve gained from this wont translate to any marketable job skill in the 21st century but other than that I thought it was a great video. Does anyone sell or make barrels for reproduction guns that have progressive depth rifling or is your best bet to buy an original gun?
Whitacre and Bobby Hoyt are still making progressive depth barrels.
@@papercartridges6705 thank you
Excellent presentation!
Very interesting historical information, regarding how progressive depth rifling was made and how the accuracy from progressive depth rifling was discovered!
History and guns, my favorites. Combine these with this super geeky gun tech is fabulous.
Enjoyed this presentation.
This mic is really muffled makes it hard on the folks hard of hearin
1st, THANK YOU! This information has kept me from buying a (sadly) poorly made rifle! I can NOT imagine, knowing that the rifling needs to be made MUCH deeper, Pedersoli continues to make what I am going to call defective rifles. It also has convinced me to do research on the depth of the rifling of their cap and ball revolvers. Which I am planning to buy very soon. I am glad that you made this video, and that I watched it!
Glad it was useful!
something that i thought of this morning, is the depth measured on one side, or is that measurement a total of both sides? I want to measure the rifling on all of my guns now. so I want to make sure I am doing that right. time to buy some cerro-safe!@@papercartridges6705
I really enjoyed that, cheers Brett!
Well....here's my amateur theory as to why progressive depth rifling is superior with expanding Minie type, soft lead bullets.
The bullet has, inherently, a smaller diameter than the bore. This is so it can be easily dropped down the barrel. As such, the bullet relies on pressure to expand its hollow base to contact and then squeeze into the grooves of the rifling.
Deep rifling is needed near the breech, because the bullet must squeeze far enough into the rifling grooves to ensure good grip and get the bullet rotating with the rifling but without stripping of the bullet. The high pressure of the charge detonation near the breech is sufficient to expand the bullet sufficiently to fully occupy this deep rifling.
As the bullet moves down the barrel, pressure drops. The bullet, which relies on pressure to remain expanded, will inherently contract back towards its resting (atmospheric pressure) size and diameter.
Thus, if rifling was the same depth down the whole barrel, the bullet would naturally contract away from the walls of the barrel (both in the lands and grooves) as the bullet moves down the length of the barrel. The pressure seal would be broken, gases would escape past the bullet, chamber pressure would drop, bullet galling would increase and bullet stability would decrease.
By progressively decreasing the depth of rifling down the barrel, the grooves of the barrel contract at least as fast as the bullet diameter shrinks due to pressure drop. This would greatly reduce gas escape and ensure the bullet remains tight against the rifling, thereby maintaining bullet stability.
If groove depth decreases faster than bullet diameter shrinkage in the grooves (i.e. the bullet actually got squeezed out of the shallowing grooves), then this would force soft lead back into the emerging gap around the bullet in the position of the lands.....thereby maintaining a completely gas tight seal right around the bullet (in both the lands and grooves).
Thus, only progressive depth rifling (with a carefully calculated, correct rate of groove shallowing) ensures a perfect, gas tight seal and fit the whole way down the barrel.
Makes sense to me.
en.wikipedia.org/wiki/Squeeze_bore
Watching grass grow.
interesting thank you
Great content. Did the US stop using progressive depth rifling sometime before ACW? I was thought I read that someplace. I think Enfield kept using it….
The U.S. kept progressive rifling for rifle-muskets like the 1863 Springfield through the war. I don’t know if the trapdoor Springfield breechloaders kept the progressive depth or not.
Dziękuję :D Świetny wykład Panie Profesorze :D Gratuluję prostego i historycznego wytłumaczenia gwintu progresywnego. Dobra robota !
Excellent video.
This subject is fascinating. First learned about it on the video about Italian replica rifles. Great content!
Brett great conversation as usual! Do you ever talk about “gain twist” rifling? What’s the deal with that? Keep up the great work sir!
Well done Brett.
I think the real issue with producing a true to form replica is that in many cases the cost would exceed just buying a decent genuine example from the period. Indeed even without the added cost of progressive depth rifling modern replicas are often more expensive than serviceable antiques. Everyone always says they want a modern replica of X rifle until they find out that it will cost 5000 dollars. I know I'm guilty of that.
I think we’re al “guilty of that”!!!
I think pump action rifles could have changed the game in WW1. However the economics don’t work out these days even though they did in 1890.
I think the replicas that have a chance in hell already have been tried or have been on the market for years.
@@danielcurtis1434agreed about the replicas. Though I think there could be room for some of the guns from the acw to have a modern iteration if interest in the war spikes again.
I think they don't do it because the machinery and tooling doesn't exist anymore. Still though, that's no excuse to have such shallow, useless rifling.
@@krockpotbroccoli65 yesn't
like he explained in another video, Persersoli et al making replica rifles use modern rifling tooling, which in most case is either cutting the rifling with a broach, or with a button
both of which are very expensive tools to have made, an there is a limit to how deep you can go with either as they are single pass cutting tools, which are just forced down the bore with a press once and it's done
back then rifling was cut on a rifling machine, which would run a cutter down the bore at a rate given by a cam groove, and the depth would be adjusted between passes until matching the specified depth, which allowed for more specific rifling patterns, but cost more as you needed to buy the machine, but also the cutters, cams and you needed multiple passes to rifle one barrel, thus taking more machine (and operator) time, which is the real costly item as when the machine is used to make one item, you can't make another one, unless you are willing to buy a second machine and set of tools
I follow your posts because they are informative and interesting. I have a particular interest infirearms from the early to the mid 19th century. Your general post have cleared up a number of points for me and your specific dives into such subjects a s gun cotton and other innovations are full of information and add interesting detail to the period. Thank you.
Another great video.
An excellent and entertaining video, thank you Professor 😉 seriously good knowledge.
18:20 I can understand why recreating the progressive depth rifling would be difficult/ expensive to do for the repro makers, but I don’t understand why they wouldn’t at least have constant depth of a more period correct depth. Getting larger dies can’t be that difficult for the makers.
You can only take off so much material in a pass. That said they've probably shifted enough of the monkey models that there's now enough of a market of slightly annoyed shooters who would pay the $100 upcharge or whatever vs. finding an increasingly rare Parker-Hale.
Very interesting! Thanks for sharing!
Thank you for all the great information!
Do you have pictures or blueprints of these tools/machines that can cut progressive depth rifling? It would be interesting to do a video on the machines of that era and how they worked.
Great video. I really appreciate your efforts! You're visuals are great!
Great video!
My question is... HOW did they cut them progressively?
Interesting stuff
Very informative, as always. I had forgotten about this, I own and have read Manns book. Do you sell a book on paper cartridges? I see a few books on your your bookshelf that have the same title.
I have one book specifically on the development of the Enfield paper cartridge, “The English Cartridge” is available on Amazon.
@@papercartridges6705 thank you
Really enjoyed that video. So I have a P-H early British P53 that I know has PR, but I also have a contract original P53 from 1862. Would the contractors have used PR by then?
Yes. By 1862 it should have progressive rifling, or it would not be accepted by the inspectors for military service.
This should really have come with a medical caution
Perhaps the marketable job skill would be to learn how to recut those modern made barrels to give them the proper rifling form. I could see that as an interesting project to consume a few years. Meanwhile I'll stick to my PH reproductions.
Just wondering, with the modern constant depth rifling barrels would a copper bullet made to the minie or Pritchett form perform better or is it about the same regardless of whats used?
your outfit is impeccable !
your seperate collar shirt is my favourite !!!!!!!!!!!
A few pictures, diagrams or photos would be perfection.
I made the best diagrams I could, with my capabilities. It’s very hard to illustrate a few thousandths of an inch variation in a rifle groove.
DAMM good history video👍👍
I watch Cap & Ball, and C&rsenal, so I found this topic very interesting and informative, just for its historic value !
I'm also an EE, and have been using an programming microcontrollers (uC), almost since their inception. But as a hobby, I design analog circuits (no digital parts, as those uCs) that wouldn't even been economical in the past, but do mostly as an interesting deviation, that maybe a friend, in the hobby, might employ, but has no benefit in anything marketable.
Kind if off topic but is it possible to use a burton bullet in a Pritchett style cartridge? I like idea of just breaking off the bullet from the powder cylinder instead of clumsily taking it out of the wrapper. The reason i ask is because Pritchett bullets are rare and hard to come by, even the molds, while burton bullets are everywhere. Perhaps this is an idea for an experiment video?
Most other European cartridges used a “Burton” style bullet in the paper patched cartridges just like the Pritchett. The only requirement is that the bullet be sized small enough that it fits into the muzzle while still wrapped in the paper.
So, anyone know where I track down a decent attic-find Pattern 1853 with progressive-depth rifling?
Very interesting listen! I never bore of these videos. Hearing you discuss it a few times now I am determined to get my Italian 1861 rebarreled to have the correct rifling. I looked up the two barrel makers you mentioned in the other video, Whitacre and Bobby Hoty. Do you recommend one or the other or either one a great choice to go to?!
Hoyt will ream the old rifling out, and insert a sleeve where new rifling will be cut. Whitacre will make a whole new barrel to original specs. Hoyt is 250, whitacre is in excess of 6-700$ with sights. I have a 3 band 1861 whitacre and a 2 band relined by Hoyt colt special. Both are equally accurate.
@@johnwestenberger6241 Thanks! That’s very informative. I imagine the sights currently on the rifle work fine with the sleeved barrel. A lot to think about.
What companies offer barrel relining services for existing Italian rifles? Who produces new barrels with progressive depth rifling that fit on Italian guns?
Bobby Hoyt can reline a barrel with progressive depth. You can find his contact info online. Dan Whitacre can make new barrels, his website is Whitacre’s machine shop.
Ah, professor, but how did they do it?
I can't see them rifling in quarter lengths and then pulling a spring loaded cutter through to smooth the gradient as an industrial ptocess.
The rifling machines had cams that applied the appropriate pressure on the cutting blades as they were passed through the bore. It could also be done by manually applying shims, which is how it’s typically done by barrel makers today.
@@papercartridges6705
Huh, interesting.
Cams, not a involved gearing system. OK. thanks for the information.
Ok, I understand How progressive grooves work, if not why, but, How is it accomplished?
If you were to measure at the lands with a bore micrometer, at the breach, and at the muzzle are they going to read the same internal diameter? If you took a barrel and turned it down on a lathe so that the muzzle Outside Diameter is the same as the breach OD, and measured from the groove to the OD, are they going to be the same at breach and muzzle?
Bore is same length of barrel. Grooves deepen at breech end.
Machines used to accomplish this cam the cutting tool deeper in a uniform slope as the tool approaches the breech and then shallower as the tool is withdrawn out the muzzle.
@@gonatas1 Thank You!
Progressive rifling sounds like it's was a purposely done...the surprise was the accuracy was improved.
Gotta luv the French..
Their engineering is quirky but in many ways better...BTW luv French cars,
Motocycles, & military hardware.
Thank you for the education, it is nice to know more about the rifle that I hold in my hands, especially the unseen stuff that is inside. In my case it is a Colt 1861 Special Contract Musket which is marked 1864. I find the the technical information very interesting, can you tell me the source documents that you show as I would love to find out more. Don't get me wrong, listening to you is great (which is why I'm here) but I also like to read and re-read the original technical books if possible...
... and thanks again for taking the time to put this together. 👍
If I recall, most of the original sources are from Major Mordecai’s report from the military commission to Europe, and from the Ordnance report of small arms experiments in 1856, both available on Google Books.
@@papercartridges6705 Thank you for the info, it is very much appreciated. I love going through the original documentation as it gives an insight on what was going on at the time. You can guess where I'm off to next and you now have a new subscriber. Thanks again for what you do, it's appreciated by many. 👍
Might there be an advantage in the progressive rifling reducing the profile of the flying bullet - in pushing down the spiral fins that form on the bullet when it bullet first expands?
I wonder if anyone can do this to a rifle that already has a constant rifling. Sure would like to have it done to my black powder gun
They will probably spend more time "chasing the thread" than actually cutting.
Oh, yeah. There's a comment in the video that led to this one that speaks of a company that does progressive depth rifling.
I think he said Richmond and mentioned a $250 cost.
The progressive nature and decreased diameter is the principle behind squeeze bore designs to boost velocity.
In WW2 the German army had a squeeze bore anti tank gun with tungsten penitrators.
It's still exceptionally accurate 😉
The British too also dabble to the that concept too called littlejohn adapter for the 2 pounder guns
🥇🏆
The audio sounds off at the start of the video.
I’m sorry, I had a cold.
Oh bugger, I have gained new knowledge of little practical use in the modern age but alas have forgotten how to tie my laces😢humbug
This is a great video, but I am very dubious that progressive depth rifling is any more accurate than constant depth rifling of adequate depth. I have seen many photos on the Shiloh Sharps board of snow bank recovered bullets that show even 1:16 alloy fills the tinest of voids. You can even see a line where a paper patch ends don't quite meet. I have talked to several N-SSA top shooters who will say that a constant depth rifling is just as accurate. I am not saying you are wrong it just dosen't make good sense to me why the need for progressive depth rifling rather than deep enough rifling to grab the bullet. I can see how a fouled barrel could shoot better with progressive depth rifling, but that is a different story. It would be super interesting to get a high speed camera to see if the thin rifling are failing to stablize the minie as compared to a Whitacre barrel. I suspect you are correct, but I think a .15" constant depth would stablize the minie just fine.
As to how progressive rifling works we need to look to the Bernoulli effect as to how that works 😊
Didn't the French develop a rifle that was smooth bore except for the last 4" from the muzzle was rifled. Examined by other countries revealed it to be as accurate as any rifle of the period.
The "Paradox" shotguns made by Holland and Holland use that. One barrel single ball, the other shot.
How do you make this rifling?
Wouldn't this also allow for less fouling? Gives more place for the carbon to build up?
That would make sense to me.
Isn't this in effect a kind of mild tapor bore? It reduces the area of the bore, no? I would expect that this might well increase the accuracy of any rifle, not just an expanding bullet muzzleloader. It would be really interesting to try a 5R gain twist, progressive depth breech-loading rifle. Could call it "Kitchen Sink" rifling because you're throwing every rifling tweak you can think of at it.
When was the progressive rifling abandoned? I'm assuming some early cartridge rifles were progressive because of all the muzzle loaders that got converted. Was it is copper jackets or smokeless powered that pushed the change back to constant depth?
Breechloading bullets, forced into the rifling, don’t need progressive depth. It’s really only useful for the very narrow, specific instance of a muzzleloading rifle firing an undersized, short, large caliber heavy bullet that has to expand into very slow twist grooves
@papercartridges6705 thanks for the reply!
Would a compression bullet work better in repo rifled muskets?
Probably would. Yes, as long as it is a snug fit in the barrel. The constant depth would not matter as much with a tight compression bullet.
Hey pal! It is me again, I have commented over your recent video about the "worst" rifle in the civil war, I wanted to say i have a problem, I have adhd, Not only that, Autism, that means My topics tend to be narrow, can yoy advice me how to hyperfocus on things i may like at least, but not narrow on? ❤😢
I do not actually have a narrow topic, at least not yet, im 16, plus my autism is very mild and high function, maybe thats why.
So please, can yoy give me advice for finding something gokd to waste time on and hyperfocus?😊
❤❤
Do you know the groove depth on an Armsport Richmond carbine?
About 0.04-thousandths of an inch.
@@papercartridges6705 I have one, but after watching this video, am skeptical about firing a 60grain charge with a .574/5 minie ball. I guess, like you said, may have to adjust/experiment with the charge to see if I can discover it's best performing load.
UBER KOOL
SO DID EARLY GUNSMITHS .. KENTUCKY LONG RIFLE, DO IT IN SMALL SHOPS , TOOLS INVOLVED AND THEY MAKE THE TOOLS
MUST HAVE BEEN STILL GOING ON 1800S RIGHT 😅
Does the sharp's rifle have progressive rifling?
I don’t think so. As a breechloader, it fired a bullet larger diameter than the bore which was forced into the rifling, so progressive depth grooves would not have given any real advantage.
So I have a modern made (relatively speaking) Birmingham made Parker hale rifle 1853. I’ve been told one of their redeeming features is that they have historically accurate progressive rifling. Do you know if that is true
If it’s made in Birmingham then yes it has the progressive rifling.
i was laughing my ass off.
What you didn’t answer is why modern Italian replicas don’t use progressive rifling? And why such shallow grooves? Why not match what they did in the 19th century?
I should have mentioned I covered the Italian repros at length in my previous video, on the channel.
i think pedersoli simply don't know bout it. when i met them last february and talked about the "magic pritchett" they were not aware of the existence of such bullet so, maby they don't know about the progressive depth rifling either.@@papercartridges6705
Can't hear you
I wounder? Why? has this Gone Away? so far away?
searching for Ever better accuracy and performance how could this tech work today? with To Days Tech?
I totally could see the logic and Possibilities or Benifits with pure lead! depending on engineering or skills?
I suspect this worked with the PSI curve as the PSI droped in a different curve with or Without the Progress?
Why is progressive rifling not used today? I understand that bullet expansion is no longer a thing, but the bullet is still forced into the rifling. It seems if progressive rifling was good then, it could still be good.
A modern bullet forced into rifling has a strong super tight grip in the grooves. Progressive rifling is only really useful with muzzleloading expanding bullets that need to grab onto something as they are expanding.
I've always wondered what would've happened with expanding bullets and the squeeze bore principle.
Thanks for telling the truth about Pedesoli repos. They are over priced shit. Traditions is another one I would never buy too. All more modern BP rifles are tight bore and require expensive proprietary bullets. It's all marketing bs.