Bullets, bigbore, medbore, smallbore anyone?

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  • #16588
    dougroundup
    Participant

    Ok, obviously I am a newb here.
    But I have been pouring over many of the various posts and I am absolutely fascinated with the great work of many talented enthusiasts that so generously share their talented experience and are so generous in documenting and discussing what I see as the cutting edge of recreational shooting sports of the future. Gentlemen, I want what you got and do what you do. I want to be a part of… I cant fake or pretend to having anything great or profound to contribute but I would like to start some discussion and postulate the following for your expert discussion and thoughts.
    Bullets, slugs, casting lead, or boolits ive seen it referred. Big bore has been done in all forms from slug to roundball and even diablo conventional pellets. Cedrics videos which I love has helpped popularize long range, with Doug furthering the great works of those highly esteemed works of the previous masters like jack haley or even dennis quackenbush!
    The casual observation has been the progression from .308 down to now is the .257 (“medbore”).
    It seems that speed does play a large role as so eloquently someone else posted. Traditionally a major limit has been the physics of approaching mach speed and overcoming the poor ballistic coefficient of diablo pellets . Before the popularity of the .17 hmr, I had went through the trouble handloading the centrfire .17 rem cartridge for the Contender Pistol . Definately a trial in dexterity and vision seating that little pill on a necked down .223 case. I can imagine the pain casting tgesr things but wouldnt a .17 bullet of around 40 to 50 grns have a decent b.c. and good chance at being the hyper velocity rnd to consistiently achieve accuracy at mach speed?

    #194423
    leadlofter
    Participant

    I think the problem is casting the bullet so small and this makes it harder to have more consistency between bullets thus shitty grouping would occur. I know I read that people wanted to shoot slugs in .22 but making the bullets was too hard. I had thought of your same vision as I shoot the .17 hmr myself thinking it would be a great round in an air rifle and wish someone would say it was possible

    #194426
    dyotat100
    Participant

    One of the problems is that the smaller the bullet the harder it is to get fps. There is a smaller surface for the air to push on.

    #194427
    slayer5
    Participant

    I use Mr Hollow points bulltes , some like them some do not. I think if you cast your own you can be more selective and particular increasing accuracy. I do not have time and find his bullets in .45 plenty accurate for my 50 and 75 yard plinking!
    You will find those going for real long distance shooting rarely use pellets and most cast.

    #194443
    knifemaker
    Participant

    I love my HMR but I gotta tell you, it takes a back seat to my .257 Talon/Dor. I shoot maybe 100-200 rounds of HMR a year, and literally thousands of .257. 😉

    The problems you are going to get into with a .17 bullet in our guns are several.

    One, Very difficult to cast for. Another, As Cedric pointed out, not enough area on the bullet to really get the velocity we want to be able to take advantage of the High BC.

    But the biggie is that even if we could cast them well, and push them at a little higher velocity, there is the transition back thru ultra sonic in a fairly short distance, that would destabilize the bullet.

    For it to work well for long range, we would need at least 1500 to 1600fps, and for 300 yard shooting, probably at least 1900. Just don’t’ think we have the technology to get there yet in the PCP air guns.

    Would be fun though!!

    #194507
    tofazfou
    Participant

    DOUG,

    1st. thanx very much for following and understanding the long range game with airguns. We are at a great point right now as we are just starting to bring some of that powder burner (PB) theory into airguns. And so far, taking and using the PB theory (bullets and twist rates) is why we r having so much success.

    A 17 at that weight would in theory be very awesome and have a pretty high BC. And at this stage, THEORY is the problem. It would be soooooo nice if someone would throw together a 177 cal, high power airgun along with some SLEEK bullet molds in 177 and make them in a BOATTAIL design to test out for us…. Spare no expense.

    Part of the problem with a bullet that heavy in 177 also would be having a barrel with a twist rate of 1-4 through 1-6 made……lol. Ok, 1-4, 1-6 twist rate was just a guess but im sure i’m not too far off…..lol.

    So airguns of today simply copy what is already been done/available in he PB world only at much lower FPS due to the power plant of the modern airgun (compressed air of up to 4500 psi vs 50,000).

    Part of the reason big bore airguns are so successful (all airguns) is that the projectiles stay BELOW supersonic. Now, subsonic (due to lower operating pressures and bullet weights) speeds combined with HIGH bc bullets such as 243, 257, 6.5mm, 7mm and 308 are why we can still reach out to 700 yards with much success. But even in these calibers, its been a stretch to get someone to even consider them in an airgun platform. This brings the late Jack Haley and some European guys to mind and I truly thank them for giving these wonderful calibers a go. We are just starting and if I had my way, along with plenty of money and a full time machinist, I would go at this full steam ahead and have something new for you guys about every month…lol. I have the ideas but just not the resources and that’s the part that sucks.

    I agree with MIKE also, my 17 hmr takes a back seat to my 257. hell, even a 25 gr 17 bullet at 1000 fps would be pretty fun I think

    DOUG NEEDS TO SPEED SHIT UP DAMNIT. I got projects to create and he is MY PERSONAL machinist……. :rofl:

    #194580
    knifemaker
    Participant

    :rofl: Not gonna happen. :rofl: Doug just has so much on his plate! 🙁

    #194611
    rj-porter
    Participant

    Hey guys thanks for being douche bags and leaving me out of the mix. What do I know about the 257 I only owned the first one ever made. Fuck me.

    #194614
    hoot
    Participant
    quote rj-porter:

    …Fuck me.

    No disrespect intended ‘RJ’…but can you post a few pics before anyone commits?

    Thank you for your consideration in this matter….

    Kindly ‘Ol Uncle Hoot:

    #194615
    hoot
    Participant
    quote Tofazfou:

    DOUG,

    A 17 at that weight would in theory be very awesome and have a pretty high BC. And at this stage, THEORY is the problem. It would be soooooo nice if someone would throw together a 177 cal, high power airgun along with some SLEEK bullet molds in 177 and make them in a BOATTAIL design to test out for us…. Spare no expense.

    Part of the problem with a bullet that heavy in 177 also would be having a barrel with a twist rate of 1-4 through 1-6 made……lol. Ok, 1-4, 1-6 twist rate was just a guess but im sure i’m not too far off…..lol.

    Sound technical points ‘Tof’, a .17 Spitzer boat-tail hollow-point would be a treat to push to the limits, especially if it is a long slug. (The Swedish 6.5X55…a .25 PB with a looong bullet, has an excellent, near perfect BC, and was even used to drop elephants with head shots!)

    With my AR-15, I read that any bullet in the sub 50gr weight range, requires a much slower rifling twist, as the faster barrel twist rates of 1:7 or higher, generates such tremendous centrifugal spin that the copper cladding on the lead actually is ripped off, and the slug disintegrates in flight.

    A “Smooth Twist” barrel, might be able to have those last few twisted barrel inches rifled to the slower twist by a qualified machinist, as it doesn’t really have a rifling cut into the barrel end to begin with. Just a thought…

    There has simply been SO much advancement in pcp’s, compared to just a few years ago, that a body doesn’t know where to start. That Evanix Tactical is certainly pretty, in an ugly functional sort of way. I’d love to stick a modified long .17 barrel on that bad boy, and see what happens if the slug weight were to get up to 40 to 50gr in a Spitzer, boat-tail configuration. I’m starting to sweat just thinking about it.

    Hoot:

    #194630
    dougroundup
    Participant

    Hey guys, thanks so very much for reading and contributing to one of my first orignal posts.
    Hey mom! Look at me, I am becoming a part of…. the other kids let me step onto the playground!
    So it sounds as if something that I have pondered does make some sort of sense in the fact that if it was reasonably technically possible, it would be desirable to have a heavy enough .17 slug besides a common diablo pellet for a projectile.
    TofFu, dude you not only make some awesome videos , you are very clear and concise with your explainations and general knowledge of theory. I am grateful for your participation and very nonpretensious mannerism. Everyone here on this Forum have so much experience and expertise. Sharing the knowledge, you guys are all so approachable. I have been meeting some real stand up guys. This is a gentlemans hobby.
    Ok I will keep my awe in check…. I dont wanna leave an impression that I in anyway subscribe to any type of that mancrush business..
    Some excellent technical points that all seem to have merit. After a short bout with handloading .17rem and trying to work with such a little pill, I just dont see it being hand casted by anyone but the most very extreme of obsessive compulsive. Trying to maintain uniformity would be another mentioned obstacle. However, after thinking about it further. I kinda started thinking about how much casting lead really does kinda suck and as a plumber I am glad that I never had to deal with leadoakem belled cast fittings. The solution would be to draw out lead rod and swage our .17 fodder and then strike and size it through a couple of dies. Hemostats might come in handy to handle your creations. The other hurdle would be that extreme amount of spin that woukd need to be imparted upon such typically small B.C.? As for pressures,,,, it seems current trends seem to indicate that even though manufacturers would never wish to put themselves in liable situations, more and more of the serious enthusiasts continue to push the upper limits of HPA. Increasing working pressures are obtained as more and more compressors are available to individuals for personal use and misuse too. Seems like 2800psi was the common before it was pushed to 3000. Now what are many guys doing? Kinda bumping it up to 3700 now? . Now that must really be an adrenaline rush in a sorta roulette type of way? Wont be long way to4500? I predict. Next stop along the guage, do we hear 6000? Has anyone documented 6000 shooting slugs? I guess that the whole issue with still not sustaining supersonic flight for a long enough of a duration to go the distance is big bummer that linits the usefulness of going there. What about propelling with exotic gasses? Or even some sorta semi combustionable? Or externally excited energy source to excite or move gas molecules in a really fast way that doesnt make for a spontaneous reaction. Such as the pressure induced by steam?
    Ok I might be getting a bit too far out there. The state of technology these days is really truly lumited by the shear amounts of expense that can be put behind an ideal.
    Similarly , despite my fascination with the forefront of what you guys are doing here… my insecurity and self doubt kinda grounds me and is trying to sabotage me before I get started . I find myself questioning myself and my capability. Certainly there is a finacial obligation that must be made as a cost of addmission but also I question if I can afford the dedication and obligate the time to invest into this advocation. If I continue to hag out at the barber shop I amcgoing to get a haircut…. I think its prolly too late anyways because your disease of addiction to this is infectious. I got my condor frame already and just gotta learn how to get my lathe wired up and how to gain the skils to put it to proper use. I dont suppose those skills exactly come overnight. But doesnt sound as if Dougs to do list is getting any shorter either nor is getting faster from what we just heard :rofl: Oh yeah this new Condor came with a dreaded .177 barrel too.
    Kinda off topic but whatta bout some of the offering being sold commercially for .257 such as the”drop in” .257 barrel offered by RL and their flavor of extreme valve? Can it stack up anywhere near with what Doug has created?
    Wouldnt be cool if doug gave me a crash lesson on how to use my tooling and I could help him with production….. Doh!!! I am just jesting and joking around . It would be cool if I was really such a quick study and had the ability to fully commit to such project!
    Gotta frame so I guess ya guys are kinda stuck with my noob and inexperienced wannabe ass for the moment. Thanks for the identifying scarlet letter that puts me out on front street too! 😳

    #194686
    tofazfou
    Participant

    Doug,

    I can talk this stuff all night long.

    Actually 4500 psi is already being done with the Hunter Extremes and the XP airguns. Well, IT’S BEEN DONE for years now.

    Here are some CURRENT problems that I see with that high of a fill pressure (6000 psi). 1, is that all internal parts will have to be made pretty strong. Especially the valve stem. 2, is the ADDED wear on many parts including the hammer and valve stem. The more internal tube pressure the stronger parts have to be cause the harder the hammer has to slap the valve stem to open it. PLUS, it gets SLAMMED shut much harder too. 3, is finding a source to fill those guns that high. Something besides the BOOSTER pump which is an awesome tool. Of course airtubes will have to have thicker walls probably. But, it can be done for sure. Todays metals are hella strong and our fill pressures are DANGEROUSLY strong but nothing like the pressures a 60000 psi PB cartridge can make.

    To be honest with ya though, a 4500 psi fill in the right caliber diameter and valving can make some serious speed and power. Let alone 6000. Hell, at only 3200 psi, my TD257 pushes a 70+gr/.129 bc bullet at over 1010 fps on its Med/High setting so imagine what a 4500 psi fill could do……lol! HOLD ON BABY, THIS NEXT SHOT IS GONNA HAVE A CRACK TO IT :rofl:

    #194714
    knifemaker
    Participant

    As to the exotic gasses, Helium works very well. But leaks like a sive and the price has gone thru the roof!

    Sadly, semi combustion would make it legally a firearm. We don’t want those headaches. The longer we can fly under the radar, the better! 😉

    Knife

    #194819
    dougroundup
    Participant

    Hey thanks guys for answering my questions and particpating in this conversation.
    Reading this thread I have noticed that much of pondering, ideas and questions do really indicate my inexperience and novice knowledge of the pneumatic air rifle in general. So I am very appreciative of everones paitence.
    As Cedric had said , I think that theory aside its really up to someone to actually experiment and give an idea a try. The investment someone is willing to place in the idea is going to be proportionate to how strong they are in their belief of the concept…m Of course a grasp of that theory and an experienced understanding of whats goin on and where you are going is greatly going to increase your goals most efficient and effectively. If there is any chance at reaping a tangible return or advantage to investment in experimentation, likely somebody would be going there. Seems technology in the modern world is such that if we can throw enough money at something , it can generally be made possible. We are also at a point in this world that we better manage and realize the limits of our resources.
    Right now it appears that the “medium” bore air rifle is where it is at… at least as far as working with a true bullet for projectiles.
    I have noticed that there was a brief moment of popularity with the .20 caliber guns being introduced by a growing number of manufacturers. I assume that likewise the ammo was being produced by various manufacturers? Of course the only .20 cal. type of any kind of round that I have ever been familiar was that Sheridan pellet for the BlueStreak . It was a rather proprietary design that seemed to be just a hollow cylndrical “barrel” shaped thing with a solid nose. It did not have the familiar shuttlecock shaped skirt of a typical diablo pellet. By todays standards I am not so sure…. but as a kid I remember those things were deadly accurate to the bird population as well as any other quarry that was unfortunate to cross a youth’s afternoon summer safari arond the nieghbor hood. I remember pumping my best friends sheridan 80 times and taking aim at a duck in a pond. The pond was located in an empty field on the next block over from my friends house. We were sitting on the upper floor of his multi level parents house , outside on the deck. I was resting the the Sheridan on the railing and raisef the barrel a decent six to nine inches of elevation over the ducks head and above the lake. Just like in a Tofouzovideo, there was this knoslight seemingly long moment of anticipation as we expected to observe the pellet splash or skip upon the water near the duck….. instead this mallards neck suddenly goes limp and its head just dropped over and under into the water, submerged. My friends dad normally wouldnt like us shooting birds and such. He became aware because of all the excitement and decided to check in on us and was astonished and in such disbelief. He tells us in a sacarstic way “good one, now how ya guys going to retrieve it?” It didnt take us too long to hike over to the field and cast a fishing lure a dozen or so times to snag the duck and drag to the shore. :fishing:
    Clean shot right into one ear and out the other side. His dad made us clean and eat that duck. With my friends mom doing must of the work plucking feathers. Amazingly lucky first shot at what seemed like incredible 100+|yard distance…. or maybe just used to always taking sighter shots from that deck all summer long watching the reactive rings of waves on the surface of the water. All summer long my friend, his brothers , dad and myself would spend the early daylight evenings on that deck with the .20 trying to take another duck once they settled on the water. I think the dad even put a decoy out there once. But nobody repeated it. I couldnt even get my .177 daisy pump to maks a splash.
    I still think that to craft a smallbore bullet it might be worth trying to extrude or swage a bullet rather than casting . Just one more project to experiment and invest in I suppose.
    And I have still yet to build/assemble a gun yet. Kinda unsure where and how to start. But surely will out of necessity be more of a DIY with what I can afford as I go along…. so far got a latest generation frame with new revised trigger and safety, std valve spinlok tank combo and a spare Co2 valve and adapter body. This is my current stuff to build upon … suggestions comments? Next step or purchase?

    #195077
    tofazfou
    Participant

    Well Doug, its hard to point ya in the direction that “I THINK” you might want to go cause i simply don’t really know what your in to.

    But, you did mention long and sleek 17 bullets. So the best that i can come up with on the fly is maybe a 257 caliber with a 1-10 TWIST barrel so you can then shoot 100-120 gr SLEEK 257 cal bullets that have decently high BC numbers. Good enough to get you out to a buncha hundreds of yards….lol!

    You also mentioned casting vs swaging. Well, i haven’t seen with my own eyes and ears anyone SUCCESSFULLY (accuracy) doing it. Casting is also MUCH cheaper to do. You can also buy off the shelf bullets in 257. You can start casting for under a hundred bucks

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