RotoMetals2Titan ReloadingMidSouth Shooters SupplyReloading Everything
Inline FabricationWidenersRepackboxLoad Data
Lee Precision
Page 2 of 3 FirstFirst 123 LastLast
Results 21 to 40 of 57

Thread: Can Anyone Tell Me Which???

  1. #21
    Boolit Master
    Join Date
    Apr 2009
    Location
    What the world calls "Global Warming", we in Arizona call "Summer Time."
    Posts
    2,123
    Quote Originally Posted by JimB.. View Post
    I don’t know how you’re going to define success for this project, just wrapping a barrel or getting some clear benefit from doing so. If the latter, I dislike your design. The placement of that center nut and the differing tension on the front and back of the barrel are new variables in a game where fewer variables seems best. Heck I don’t even like the stepped profile since it’ll hold heat differently, but if that’s what folks are doing then my concerns are probably overblown.

    Think hard about sleeving rather than wrapping. You probably have to turn a profile to match a sleeve that they already make, but that’s relatively easy. A tangential benefit is that in the shopping for a sleeve you’ll learn a lot about the barrel profiles that more experienced barrel makers have selected.

    good luck, it’s always good to push the boundaries of what we can do ourselves.

    Judging from your comment I tend to think that you haven't read this thread from the beginning. Sounds like you may have jumped in near my last few posts. For me "Success" is defined in incremental steps. I want to succeed in actually being able to wrap my own Carbon Fiber barrels. This means starting with these short lengths of Carbon Fiber tubes then transferring them to my turned down barrels. This to me is doable by the average joe.

    Like you've alluded to, turning down and threading the barrel and the matching mandrels is the easy part as far as I'm concerned. It's the traversing of the learning curves involved in applying the resin properly; the optimum pattern to lay down, how best to wind the Carbon Fiber onto my mandrels and the curing of the wrapped Carbon Fiber tubes that I'm looking for success in doing. It matters not what others who have never even tried such a project define as success. That doesn't even enter into the equation. One step at a time.

    The subject of "Heat Retention" in the metal of the barrel is one I kept coming across with nearly every negative comment or opinion I read or viewed on video when I was doing my informal research in to Carbon Fiber Wrapping rifle barrels. At one point I came across a comment from one of the actual producers of Carbon Fiber Wrapped barrel. This person was fielding negative comments regarding "Heat Retention" due to what detractors deemed to be the "Insulating Qualities" of the Carbon Fiber wrapped around a steel rifle barrel. This person offered up the mathematical formulas to disprove or to take the steam out of the "Heat Retention" concerns they were continually being bombarded with. I can't remember the guys name. I think he was from Proof Research but it was a while ago so it may have been one of the other Carbon Fiber Barrel manufactures. I never did get to see those mathematical formulas but to me it wouldn't have mattered much cause I suck at math anyway.

    "Success?" To me is learning how to actually do it myself. To get a lighter weight barrel. To get a more rigid barrel. To get a safe shooting barrel. Hopefully to get a accurate barrel. To NOT have to pay seven or eight hundred dollars to someone who in all likelihood learned how to Carbon Fiber wrap their own barrels the same way I'm doing here. One step at a time.

    I don't really think that an apology is warranted here but for the sake of keeping the peace; sorry that you don't like my design. You may be even more unhappy to know that this design will be the one that I'll most likely go with as I traverse those learning curves I mentioned above.

    HollowPoint
    Last edited by HollowPoint; 12-30-2019 at 01:51 PM. Reason: mispelling

  2. #22
    Boolit Master
    Join Date
    Apr 2009
    Location
    What the world calls "Global Warming", we in Arizona call "Summer Time."
    Posts
    2,123

    It Has Begun

    In anticipation of receiving the information I was seeking from my inquiry to the gentleman who replied to my email at Soller Composites, I will begin turning my first Prototype Guinea Pig barrel next week. I have it laid out with a pencil but I'm going to go ahead and turn that barrel down, ream out the chamber from it's native 223 Remington to 223 Ackley Improved; just like the replacement fluted-barrel I now have on my Tikka Lite rifle.

    I will follow that up by making the two Compression Nuts. I think I'll wait a while before turning the thread protector though because I want to turn it to a specific configuration; otherwise I might be able to get away with just using one of the spares I have in my storage closet. As you may have guessed by now I'll be using the pattern shown in the CAD rendering I uploaded a couple of days ago.

    I debated with myself whether I should do this now or wait till I actually had the Carbon Fiber material and the Resin in hand. In the end I won that debate. The logic behind my decision was that if Soller Composites didn't come through for me after all then having a ready-to-go turned down barrel will give me more of an incentive to keep on searching for the right stuff.

    I'll be taking photos of each step as I move along. This means that any older photos I have still up on other Cast Boolits threads that I've either started or participated in will have to be taken down to make room for these new photos. As it is I've already reached my allotted limit of photo space.

    I'm dreaming of perfection but in reality I'm just hoping for the best I can do. It has begun.

    HollowPoint

  3. #23
    Boolit Master
    Join Date
    Apr 2016
    Location
    NC
    Posts
    2,863
    Quote Originally Posted by HollowPoint View Post
    Judging from your comment I tend to think that you haven't read this thread from the beginning. Sounds like you may have jumped in near my last few posts. For me "Success" is defined in incremental steps. I want to succeed in actually being able to wrap my own Carbon Fiber barrels. This means starting with these short lengths of Carbon Fiber tubes then transferring them to my turned down barrels. This to me is doable by the average joe.

    Like you've alluded to, turning down and threading the barrel and the matching mandrels is the easy part as far as I'm concerned. It's the traversing of the learning curves involved in applying the resin properly; the optimum pattern to lay down, how best to wind the Carbon Fiber onto my mandrels and the curing of the wrapped Carbon Fiber tubes that I'm looking for success in doing. It matters not what others who have never even tried such a project define as success. That doesn't even enter into the equation. One step at a time.

    The subject of "Heat Retention" in the metal of the barrel is one I kept coming across with nearly every negative comment or opinion I read or viewed on video when I was doing my informal research in to Carbon Fiber Wrapping rifle barrels. At one point I came across a comment from one of the actual producers of Carbon Fiber Wrapped barrel. This person was fielding negative comments regarding "Heat Retention" due to what detractors deemed to be the "Insulating Qualities" of the Carbon Fiber wrapped around a steel rifle barrel. This person offered up the mathematical formulas to disprove or to take the steam out of the "Heat Retention" concerns they were continually being bombarded with. I can't remember the guys name. I think he was from Proof Research but it was a while ago so it may have been one of the other Carbon Fiber Barrel manufactures. I never did get to see those mathematical formulas but to me it wouldn't have mattered much cause I suck at math anyway.

    "Success?" To me is learning how to actually do it myself. To get a lighter weight barrel. To get a more rigid barrel. To get a safe shooting barrel. Hopefully to get a accurate barrel. To NOT have to pay seven or eight hundred dollars to someone who in all likelihood learned how to Carbon Fiber wrap their own barrels the same way I'm doing here. One step at a time.

    I don't really think that an apology is warranted here but for the sake of keeping the peace; sorry that you don't like my design. You may be even more unhappy to know that this design will be the one that I'll most likely go with as I traverse those learning curves I mentioned above.

    HollowPoint
    I’ve been following this, in fact post #9 is mine. It seems that you’re defining success as learning something, and that happens if what you try works or doesn’t and so your initial design is largely irrelevant. It still seems unlikely to work, but I know very little and it could turn out to be the best design ever, won’t know for sure until you try it.

    About the heat, the math is more complicated than I remember, but I think the insulating capacity of the carbon fiber is probably offset by it’s far lower heat retention capacity, so in effect a much much larger percentage of the energy gets pushed out the front of the barrel rather than absorbed by the barrel, so the bore cools more quickly. Probably hits practical limits as you increase the rate of fire, so for example you’d probably burn out the bore more quickly in full auto, but that’s not what you care about.

    Anyway, no apologies necessary, go play with it and let us know what you learn.

    Edit to add: when I said sleeve I meant sleeve and not tube. I believe that a sleeve is woven rather than wrapped, and it is not ridig. You insert your barrel, turned to a specific profile which fits snuggly, into the sleeve and then go through the curing process. Again, I know next to nothing about this so maybe I dreamt this.

  4. #24
    Boolit Master
    Join Date
    Apr 2009
    Location
    What the world calls "Global Warming", we in Arizona call "Summer Time."
    Posts
    2,123
    I got a chance to chase the threads on my donor barrel yesterday morning. Since I'll be using the Savage-Barrel-Nut method of installing my barrels onto the receivers I needed to extend the threads on the tang by another 1 1/8". I'm going to also be installing an additional recoil lug as well. Tikka rifles come with just a sliver of a recoil lug that fits into a shallow milled slot on the underside of the reciever. It fits neatly into the inletting of the stock but it has always looked kind of insufficient to me. I'm sure this isn't completely true cause the three Tikkas I've owned over the years have all shot very accurately but, the factory recoil lug on my rifle was made of aluminum and I could clearly see the indentations on the surface of it due to even the light recoil of the 223. I actually replaced my factory recoil lugs with a DIY Stainless steel lug last year but still, I'm going to add that additional recoil lug for the sake of redundancy.

    Today I hope to ream out the chamber to 223 AI. Then I'll fish around in my stash of metal stock to see if I have any stainless steel I can use to make that recoil lug, the compression nuts and the thread protector.

    I've been searching the internet for maker/seller/vendors of pre-made Carbon Fiber tubing with the correct properties and dimensions for this application. I've come across two online vendors of Carbon Fiber Tubes and I've sent out email inquiries to each. I figure that at this point in my foray into Carbon Fiber wrapping my own barrels it would be more financially feasible to buy pre-made tubes rather than to spend the money on building my own jigs and Carbon Fiber/Tow and Resin and other peripheral items I'd need to wind my own Carbon Fiber tubes. If I can't line up a provider of Pre-made Carbon Fiber Tubes that are able to withstand high heat and have a rigidity equal to or better than the stainless steel that the barrel is made of then I'll go ahead and start making plans to wind my own Carbon Fiber Tubes.

    Next week will be what I consider to be, "After The Holidays." If all those email inquiries I've sent out just before and during the holiday season haven't been replied to by then I'll start making phone calls instead. I'd like to get this barrel done in a couple more months if not sooner. The weather then should be ideal for field testing.

    I shall return.

    HollowPoint
    Last edited by HollowPoint; 01-05-2020 at 10:01 PM. Reason: misspelling

  5. #25
    Boolit Master
    Join Date
    Apr 2009
    Location
    What the world calls "Global Warming", we in Arizona call "Summer Time."
    Posts
    2,123
    Out of the half dozen email inquiries I'd sent out during the holiday season I've gotten three replies this week so far . Two of those replies sounded promising.

    Unfortunately none of their listed in-stock and suitable-for-this-application Carbon Fiber tubes were of the correct dimensions. They did say that they could make some up in the dimensions and the correct heat resistance I was looking for so in my latest reply to their email replies to my original inquiry, I asked them to send me a quote for the cost of making up a very small number of such tubes for testing purposes.

    Incidentally; what I'm looking for are Carbon Fiber Tubes with an inside diameter of .625" and an outside diameter of 1.0". One of those respondents makes them in any length up to 96". The other makes them as long as 105". Neither mentioned anything about minimum or maximum orders so I don't know if they are willing to make up just a couple of 12 or 24 inch lengths to begin with. I'll have to wait and see what they have to say if or when they contact me again. If they make no effort to contact me again that will be a pretty good indication that they don't want to mess with a Starry-Eyed Small-Timer like myself who only wants a small number of these Carbon Fiber Tubes.

    In my mind the worse case scenario would be to order a slightly larger quantity of specified Carbon Fiber tubing only to find after the fact that it just wasn't working out. Hopefully they'll get back in touch with me cause buying pre-made tubing with the right characteristics for this barrel wrapping application would help me complete this project a whole lot faster than having to accumulate the components and the hardware to wind my own tubes.

    On the home front; I'll be finishing up the machining of my donor barrel in the next couple of days. I don't want to do any actual turning down of my donor barrel until I get my hands on the correct Carbon Fiber tubes so I can get exact measurements off of them. I mentioned before that I had already reamed out the existing chamber of my donor barrel; as well as extending the threads on the tang. Yesterday I made up the new recoil lug I'll be using and today I worked on the new barrel-nut for this setup. That new barrel-nut should be done tomorrow morning. I'll take some photos at that time and post them for you all to see.

    The way I picture it in my mind is; any machining that needs to be done is pretty straight forward. I think anyone with a metal lathe and a bit of lathe turning experience can do that part. The difficult part for me is having to rely on the expertise of others when it comes to the Carbon Fiber tubes aspect of this project. I have a pretty good idea of what it will take if I have to wind my own Carbon Fiber tubes. I mean in terms of Carbon Fiber material/tow, resins and the winding jig. That puts me a little farther ahead than I was when I first posted this thread. Back then I just wanted to know which was the correct resin to use. I found the answer to that and having figured this much out I would still prefer to proceed using pre-made tubes and then once I have the bugs worked out of that I can then look toward possibly making my own Carbon Fiber tubes if I decide to rebarrel any of my other rifles.

    Slowly but surely things are moving forward.

    HollowPoint
    Last edited by HollowPoint; 01-08-2020 at 01:17 AM. Reason: misspelling

  6. #26
    Boolit Master
    Join Date
    Apr 2009
    Location
    What the world calls "Global Warming", we in Arizona call "Summer Time."
    Posts
    2,123

    Carbon Fiber Tubing Has Been Ordered

    Those two respondents to my initial inquires about the appropriate Carbon Fiber tubing for this application never did get back to me. One of those two respondents had recommended a specific Carbon Fiber Tube for this application but as I mentioned before, the outside dimensions were a bit too small if I were to be working with the one-inch diameter barrel blanks that I planned on using if or when I decided to re-barrel any of my other rifles.

    This time out, since I'd be working with the take-off barrel from my recently re-barreled Tikka-Lite rifle; as crazy as it sounds, I was so fixated on wanting the one-inch outside diameter Carbon Fiber Tube that it didn't occur to me that my take-off guinea-pig barrel had already been turned down from the factory so that the Carbon Fiber Tubing that the email respondent from RockWest Composites had suggested would actually be close enough to what I needed for this project.

    So; all of that to say, I have now ordered two short lengths of the Carbon Fiber Tube that was suggested for this particular manner of application. They will be installed in the manner I had described in my uploaded CAD rendering.

    Now I wait for deliver before I can proceed any further.

    On the home front; I finished up the all of the machining tasks I could without having those specific carbon fiber tubes on hand. Once they get here I can then get the measurements I need to start the lathe work that will get them down to the diameters I'll be working with. I still haven't taken those photos I mentioned. I'll try to do that today sometime but my front and back lawn is in dire need of mowing; among other things that need doing.

    Also: I will be attempting to contact the moderator of this section of the forum to ask if it's possible to change the title of this thread. If it is possible, I will be asking if they can change the title of this thread to, DIY CARBON FIBER WRAPPED RIFLE BARREL. Those of you who happen to be following this thread under the existing title, please keep an eye out for that possible title change.

    My original "Inquiry-Sounding" title now somehow seems insufficient or misleading in that it gives no suggestion or clue about what this thread has evolved into. Although originally it was trying to find the correct bonding agent for winding my own Carbon Fiber tubes, I have since then found that answer and in the process of finding that answer I found also that I could simply buy Carbon Fiber Tube with the appropriate characteristics instead. (which is what I've done)

    I'll be back.
    HollowPoint
    Last edited by HollowPoint; 01-09-2020 at 08:33 PM. Reason: misspelling

  7. #27
    Boolit Master
    Join Date
    Apr 2009
    Location
    What the world calls "Global Warming", we in Arizona call "Summer Time."
    Posts
    2,123
    Here's a hastily taken and edited photo of the chamber end of my Tikka-Lite donor barrel. It's a tad blurry but it's good enough to give a good idea of what I was attempting to describe in my previous posts.
    Things are moving along now so I hope to have this project done sooner than I expected. Because my Tikka rifles are both barreled using the "Savage Barrel-Nut" method it means that swapping barrels should be relatively quick and easy. I will probably have to fabricate a reciever wrench that will allow me to keep the recoil-lug in the right orientation as I screw this new barrel into place but I'm thinking that this will not be very difficult either. I just have draw up a model and convert it to G-Code, then I can machine it on my hobby mill. I have enough metal stock laying around for this.

    I'll be back when the Carbon Fiber tubes get here.

    HollowPoint
    Attached Thumbnails Attached Thumbnails TikkaCFB.jpg  

  8. #28
    Boolit Master
    Join Date
    Apr 2009
    Location
    What the world calls "Global Warming", we in Arizona call "Summer Time."
    Posts
    2,123
    No sooner that I order those tubes I mentioned in my previous post to keep this project from going idle on me then this morning I finally get a reply from one of the manufactures of Carbon Fiber Tubes that had previously contacted me. (Dean Comstock from Dragonplate Composites) I wish he'd of contacted me a day earlier but, Oh Well. I had already order tubes from his competitors at RockWest Composites.

    He did have what I consider to be a bit of good news though; and that was that if need be they could make up custom Carbon Fiber tubes with an even higher heat resistance of 500F degrees. I would've preferred this higher tolerance to heat than the 250F degree level of the tubes I've already ordered. In the same way that I asked the guy from RockWest Composites to give me a written estimate of what it would cost to have some custom tubes made up and what they accepted as a minimum order; I asked this guy from DragonPlate Composites the same thing.

    The RockWest guy never did get back to me when I asked him to send me a written estimate of what it would cost for them to make up some custom tubes so there's a chance that this guy from Dragonplate will also not be heard from again. Having ordered those tubes yesterday, at least now I will have some Carbon Fiber tubes I can do some testing on. I plan on running over to my local Walmart and picking up one of those cheap ten or twelve dollar pistol-type laser thermometers so I can check for myself to see exactly what kinds of temperatures I'm really dealing with when shooting my rifles in the typical way I do. If that 250 degree level of heat resistance isn't reached during one of my typical range sessions then I'll know that this will most likely do for the average-joe rifle shooter/hunter. Still, I would much prefer that slightly higher level of heat resistance offered by the 500F degree resin used to bond those Carbon Fibers into a tube.

    I may post the Dragonplate guy's email reply so you can read it for yourselves to see what he had to say. In the off chance that any of you guys may consider Carbon Fiber wrapping your own barrel some day, it may help you sort out what you may need. I've been archiving any correspondence I'm having with those Carbon Fiber Tube makers who have taken the time to reply to my email inquiries. I'll be back with updates as they happen.

    HollowPoint
    Last edited by HollowPoint; 01-11-2020 at 05:00 PM. Reason: misspelling and poor grammar

  9. #29
    Boolit Master
    Join Date
    Apr 2009
    Location
    What the world calls "Global Warming", we in Arizona call "Summer Time."
    Posts
    2,123
    I finally got a reply from the guy at the RockWest Composites website. He basically suggested the very thing I had already decided to do since I hadn't heard from him in a while. That is, to try the Carbon Fiber Tubes that he had originally suggested to see if they were going to work or not. Duh.

    I'm hoping that those Carbon Fiber Tubes I ordered will be here this week some time cause I have this week free to do the remainder of the lathe work I'd need to do to get this project moving along a bit faster. This morning I pre-drilled and bored out the metal stock that I'll be making the compression-nuts out of but I really can't do any more than that till I have those Carbon Fiber tubes in hand.

    This same individual (Rylan) also gave me a general price of what it would cost for them to work up a Carbon Fiber Tube that may meet the requirements for this Barrel Wrapping application. Anyone care to guess the initial cost of having them put together a pre-made Carbon Fiber tube with all of the qualities needed to withstand the demands of this application?

    $2,300.00 just to begin with. He didn't mention any minimum purchase amounts. This is just to get the ball rolling with his people to figure out exactly what resin to use and how to best wind the Carbon Fiber Tow in order to get the optimum rigidity out of it.

    When I was gathering information about the materials I'd need to make my own Carbon Fiber tubes (minus the correct resin cause I was still looking for that information at the time) the total cost wasn't anywhere near that amount. Now I've found a couple of sources for the correct High-Heat resistant resin so even adding the price of those resins, the curing oven, the vacuum pump, the shrink tape and other peripheral materials it still wouldn't come close to the twenty-three-hundred bucks he mentioned. I understand they have overhead; probably lots of it too but, wow. And I had already come across at least one online engineering write up having to do with the optimum winding pattern to maximize the rigidity of a Carbon Fiber wrapped barrel so, it's not like that information isn't already available.

    It may be that the guy from DragonPlate Composites will contact me eventually as well with similar prices. I really won't know until he decides to get back to me. If I had to choose between the two, at this point in time I think I'd choose the DragonPlate guy; mainly because the bonding resins they use are good up to 500 degrees F.

    With any luck, after testing the incoming Carbon Fiber Tubes that are bonded together with resins said to resist heat up to 250 degrees, I'll find that they are totally sufficient for this application. If the kind of shooting I generally did involved rattling off round after round in a short amount of time, then I'd be looking for an even higher heat resistant resin but, I'll just have to wait and see how the first round of testing goes.

    Incidentally; while I was informally gathering information on the subject of Carbon Fiber Barrel Wrapping rifle barrels I also did a search on, "How Hot A Rifle Barrel Got When Fired Multiple Times?" One of the things that this internet search brought up was a video of a guy who wondered the same thing. In this video this same guy was shooting an AR platform rifle with 30 round magazines of full power 223 ammo. The barrel of his rifle was one of those factory thin barrels if I remember correctly.

    With the first mag-full he rattled off all thirty rounds in less than a minute and then he put his laser-thermometer to the barrel at different sections of the barrel; the chamber end, the muzzle end and near the gas block. If I remember correctly it measured about 175 degrees. He did the same thing with the second mag-full immediately after taking those temperature readings. I'd have to re-watch that video to be sure but I'm thinking the temperatures were in the three hundred degree range after rattling off that second mag-full. The third mag-full of rounds took the temperature of that AR barrel even higher still. This was all within the span of about five minutes or less.

    In a typical range session where I'm working up loads I'll generally fire about five rounds in the span of five minutes or so. I mention this because if this guy on the video's gun barrel temperatures reached the 170s after rattling off 30 back to back rounds, there's a very real possibility that the 250 degree heat-resistant resin used in making the tubes I've ordered will be perfectly fine for what I have in mind. We shall see.

    I'll be back as new information becomes available.

    HollowPoint

    Last edited by HollowPoint; 01-14-2020 at 03:34 PM.

  10. #30
    Boolit Master
    Join Date
    Apr 2009
    Location
    What the world calls "Global Warming", we in Arizona call "Summer Time."
    Posts
    2,123

    Surprise; My Carbon Fiber Tube Showed Up Sooner Than I Expected

    I didn't think the Carbon Fiber Tubes I ordered would show up until later this week. Because of this I had made plans to do some "Retired-Guy" stuff tomorrow. I made plans to go trout fishing tomorrow morning and I'm not inclined to cancel those plans now.

    I was surprised to see that I had been shipped out one 24" long piece of Carbon Fiber Tube rather than the two twelve inch pieces I expected. The listing for this particular type of CF tubing stated that they were sold in 12" sections. No matter. This may actually work in my favor. If it turns out that my typical way of shooting doesn't max out the temperature rating of the resin used to make these Carbon Fiber tubes, if I decide to Carbon Fiber wrap another barrel it means that I'll only have to order one more 12" section of the same tube.

    Below is another hastily taken photo of this project's progression. I ordered this Carbon Fiber Tube un-sanded. What this translates to is that the outside diameter, although listed as being .91", actually varies from .9125" or so, to .9093". If it had been sanded there at the factory it would have come in a uniform outside dimension that matched the specs on the list of various tube sizes. Using the factory contoured take-off donor barrel from the Tikka T3 Lite rifle, I can work with these dimensions even though the outside of the tube isn't perfectly uniform. Heck, I may decide not to do anything more with the outside surface of this tube until I've had a chance to test it's heat resistance and rigidity when installed on the rifle.

    A close look at the surface of this tube shows a series of right-angle lines from edge to edge on the tube. These lines were imprinted on the surface of the tube when the shrink tape was applied for the initial curing process. The photo really doesn't do the Carbon Fiber wrapping pattern any justice. In my hands I think it looks kind of cool. I had previously enlarged the inletting of my rifle stock where the barrel sits in order to accommodate the bull-barrel I have on it now so if I leave the outside diameter of the CF tube as it is, it too should fit pretty well into the stock with no further fiddling.

    I'm not doing any gunsmithing tomorrow. I'm going fishing instead. I'll be back on Thursday to start turning down my donor barrel to accept this Carbon Fiber Tubing. Wish me luck.

    HollowPoint
    Attached Thumbnails Attached Thumbnails cftube.jpg  

  11. #31
    Boolit Master
    Join Date
    Apr 2009
    Location
    What the world calls "Global Warming", we in Arizona call "Summer Time."
    Posts
    2,123

    Slight Change Of Plans

    By now most of you following this project have had a chance to take a look at the CAD Rendering I uploaded a few days back. One of the three different methods of going about this DIY Carbon Fiber Barrel wrapping project was shown in that uploaded image.

    The other two ways that I was considering as a way to tackle this project were: (I'm sure there are other ways too. This is just the three ways I was considering)

    (2) Use basically the same method of installing a pre-made Carbon Fiber tube except that rather than having two Compression-Nuts; one at the muzzle and one near the center of the barrel's length, this second method would be to just use a single Compression-Nut at the muzzle end of the barrel; provided I could get a long enough pre-made Carbon Fiber tube made with the right characteristics.

    (3) The third method of Carbon Fiber wrapping a rifle barrel would entail milling down the diameter of the barrel and leaving about three inches at the chamber end unturned and about an inch and a half of unturned barrel at the muzzle end. The Carbon Fiber Filament would then be wrapped, directly onto the turned down section of the barrel until the height of the Carbon Fiber material was level with the chamber and muzzle ends that had not been reduced or profiled in diameter. Any profiling would be done after the Carbon Fiber curing process.

    Well, I fully intended to go with my first choice; and that was to use two separate compression nuts; one at the muzzle and one near the center of the barrel's length. I even went so far as to do all my lathe work with that in mind. I profiled my donor barrel exactly as I'd planned but after I'd finished the lathe work on that barrel I got to thinking a bit more about it and, since I'd been sent out a full 24" length of pre-made Carbon Fiber tube rather than the two twelve inch pieces I'd expected to get, I decided to change my plans and just use one full length piece of tubing with one lone Compression-Nut at the muzzle end.

    I should have the Compression-Nut done this weekend along with the Thread Protector. I've already cut that 24" length of pre-made Carbon Fiber tube I ordered down to the correct length. I also milled some breather-holes into it to allow for ventilation to aid in cooling the barrel with this method of Carbon Fiber wrapping a rifle barrel. I'll take some more photos tomorrow and hopefully I'll be able to edit them and upload them on Sunday.

    It looks like I did a decent job of turning down my donor barrel because the tube slides right into place with no slop and little force needed to get it seated into position. I don't want to get ahead of myself but, now I have to determine how much torque I'll need to apply to my compression nut to get the optimum rigidity out of this DIY Carbon Fiber wrapping setup. If any of you have any good suggestions maybe you can share that info with me. In the back of my mind the torque specs of the Savage Barrel-Nut might be a starting point but I haven't decided yet.

    HollowPoint
    Last edited by HollowPoint; 01-17-2020 at 06:56 PM. Reason: misspelling

  12. #32
    Boolit Master

    Join Date
    Mar 2010
    Location
    NC Arkansas
    Posts
    1,394
    Don't know how much but concerns are: Don't crush tube - do you need to allow for barrel stretch cold to hot - will accuracy vary with torque applied?
    Spell check doesn't work in Chrome, so if something is spelled wrong, it's just a typo that I missed.

  13. #33
    Boolit Master
    Join Date
    Apr 2009
    Location
    What the world calls "Global Warming", we in Arizona call "Summer Time."
    Posts
    2,123
    Quote Originally Posted by ulav8r View Post
    Don't know how much but concerns are: Don't crush tube - do you need to allow for barrel stretch cold to hot - will accuracy vary with torque applied?
    These are all valid questions I've asked myself as well. I've been looking into the amounts that various materials expand when subjected to heat and how much they can be expected to expand.

    When I read up on some of the trials and errors of a guy named Mike Degerness I got a general idea of what to expect in regard to heat induced metal expansion. This guy Mike Gegerness is one of the pioneers of Carbon Fiber barrel wrapping. The piece I read about this guy was actually an interview done by some gun-writer some time back. In this article it touched on a number of things including the types of specialty resins they eventually formulated, the safe amount of thickness of the barrel walls as it related to the bore diameter, allowances for expansion and the exact angles used when wrapping the Carbon Fiber filament around the turned down barrels; among other things. No mention of exact torque specifications were made though. I guess this will be something that one has to figure out on their own.

    If I can find some information about thermal expansion of gun barrels I think that may help a bit. I suspect some trial and error will still be called for. "Will accuracy vary with torque applied?" I'm thinking it probably will if my Compression-Nut is over-tightened or under-tightened. If I can find the sweet spot, in theory this should mitigate any accuracy fluctuations caused by a hot or cold barrel.

    This may be a poor analogy but, if you are familiar with concrete forms; when those long and huge "T-Shaped" bridge rafters are made, they are formed around rebar cables that have been stretched tightly from end to end. These concrete forms are poured around those stretched rebar cables and when the cement has cured, the tension on the rebar is released and it constricts as far as it is able within the concrete structures. This further strengthens the forms because it also has the effect of constricting the concrete that the rebar was imbedded into.

    In a similar manner, when my Compression-Nut is tightened down against the longitudinal rigidity of the Carbon Fiber tube it should have the minor effect of somewhat stretching the barrel-metal taught. As thermal expansion occurs the section of the barrel in between the Compression-Nut and the shoulder on the chamber end of the barrel should in theory cause enough additional tension to maintain a straight bore; which in turn (I hope) will enhance accuracy. Whether it actually plays out this way is yet to be seen.

    It will be a few more days till I do any actual assembly of my barrel parts. This will give me some time to look for more information on this aspect of this DIY project.

    HollowPoint
    Last edited by HollowPoint; 01-17-2020 at 07:50 PM. Reason: misspelling

  14. #34
    Boolit Master
    Join Date
    Apr 2009
    Location
    What the world calls "Global Warming", we in Arizona call "Summer Time."
    Posts
    2,123

    Everything Appears To Be Fitting Together Nicely As It Should

    I found those equations I needed to help me figure out what I can expect in the way of Thermal-Expansion of the 416 Stainless steel that my donor barrel is made of.

    It gave me a headache just looking at those numbers. I suck at math so trying to figure out what those numbers actually meant was like trying to read Egyptian hieroglyphs. Eventually, after veiwing several YouTube videos on the subject I think I figured it out.

    The Thermal Expansion coefficients for just about any material can be found online with a simple internet search. The Carbon Fiber Tubes also have their own set of numbers so the tricky part for me was to remember to subtract the values I ended up with for the Carbon Fiber tube from the values I got for the 416 Stainless steel. If I worked those equations correctly it means that the maximum temperature that the Carbon Fiber resin is rated for, (250 F) my 18" long barrel can be expected to expand in length by .012105"..

    As I've already admitted, I SUCK AT MATH so, to confirm the numbers I came up with I'll be doing a couple of experiments next week. One experiment will be to put my 18" barrel in the freezer over night and measuring it again to compare the length I get to the existing ambient-temperature length. I keep saying that it's 18 inches long but to be more specific it measures 18.375" long. I still have to cut the eleven-degree crown on the muzzle so that will shorten my length a bit but I'll do that after I've mounted the barrel to the reciever.

    The second experiment will be to take my heat gun and heat the barrel up to 250 F degrees if I can (or as hot as I can get it with the heat gun) and then take another measurement. If the barrel does in fact shrink in the cold and expand in the heat by the amounts I've calculated then it will be a good indication of what the appropriate amount of torque should be that I'll be using to tighten up my Compression-Nut against the Carbon Fiber tube.

    Why only go up to 250 F degrees in my experiment? Because, the resin that the Carbon Fiber tube is made with is only rated up to 250 degrees F. If the barrel were to get any hotter and expand any further it wouldn't really matter cause by then the Carbon Fiber tube will most likely have failed or started to fail.

    If these experiments give me the results I've calculated, I figure that I can heat the barrel up again to expand the length again; then let it cool to just below 250 F degrees; after which I can slip the Carbon Fiber tube into place then torque the Compression-Nut to a bit past the point of being snug. It's not very scientific but after the barrel has started to cool off the metal should contract close to it's original Ambient-Temperature length. The only thing keeping it from fully contracting to it's original Ambient-Temperature length will be the Carbon Fiber Tube wedged between the Compression-Nut and the shoulder at the chamber end.

    I'll have to run over to my local Walmart store to pick up one of those cheap laser thermometer guns they sell.

    Below are a couple more hastily taken photos of what I've gotten done so far. I think I'm done with the machining part of this project. Next up will be the shooting tests to see how well this Carbon Fiber Tube holds up and what effects it has on accuracy.

    HollowPoint
    Attached Thumbnails Attached Thumbnails CF1.jpg   CF3.jpg  
    Last edited by HollowPoint; 01-20-2020 at 12:22 PM. Reason: misspelling-bad grammar

  15. #35
    Boolit Master
    Join Date
    Apr 2009
    Location
    What the world calls "Global Warming", we in Arizona call "Summer Time."
    Posts
    2,123

    Phase One Of My Thermal Expansions Test Done

    As most of you already know Thermal-Expansion takes place when the barrel of our guns get hot. There is also the reverse phenomenon that occurs when the metal of the barrel cools down. In order to arrive at a optimum torque value for the Compression-Nut of my DIY Carbon Fiber wrapped rifle barrel project I decided to undertake these tests. Phase one involved just sticking my donor barrel into my refrigerator freezer over night and then measuring any difference against the original Ambient-Temperature length of that same barrel.

    I've referred to it as "Phase One" to differentiate it from the second part of my Thermal Expansion test which will require the use of that laser thermometer I mentioned in my previous post. I did run down to my local Walmart only to find that although they have tons of those hand-held pistol type laser thermometers on their website, they have no such items in their stores; so, I ordered one off of amazon thinking that it would be here in a couple of days just like all the other stuff I've ordered off of amazon. I found out after the fact that the thermometer I ordered was being shipped to me from China. This means it won't be here for a couple of weeks. I could have also run over to my local HomeDepot and bought one but I'm afraid the cheapness in me would not allow me to pay fifty or sixty dollars for something I could get for 12 dollars; and those more expensive models were most likely made by the same little Chinese kids as the cheaper models.

    I took some photos of my cold barrel Thermal Expansion test too. I'll upload those when I get closer to testing with the laser thermometer. I was surprised that this frozen barrel test yielded any results but, it did. With the naked eye I really couldn't tell any difference between the lengths of my barrel at Ambient-Temperature and the same barrel frozen over night but, believe it or not there was a very slight difference. In my mind this means that when my laser thermometer arrives I'll be able to get some fairly accurate numbers as far as the differences in length I can expect when I shoot my barrel to a certain temperature range. I'll be interested to see if these differences come close to the numbers I came up with by just doing the math.

    The heat expansion test will be as simple as I can make it. I plan to secure the chamber end in a vice and then I'll place my digital calipers against the muzzle end; after which I will proceed to use my hot air gun to heat the barrel. If it works as I hope it will the barrel expansion should register on my calipers even if it's a miniscule difference.

    I contacted the folks over at RockWest Composites to see if they could give me the Coefficient of Thermal Expansion numbers (CTE) for the Carbon Fiber Tubes I bought from them. I figured that when they developed their tubes they did these tests as a matter of their process; Not So. The guys there didn't know either. They did offer to run those test for me though. Anyone care to guess what their generous offer would cost? I'm not kidding; they offered to run those test to find out the CTE of these specific tubes for -wait for it-; one-thousand freaken dollars. I think I'll just run my own tests. If I can't figure out the CTE numbers for these Carbon Fiber Tubes then I'll use the generic numbers I came across when I did my internet searches for this information. It is said that the Thermal Expansion of Carbon Fiber tubing is up to "Three Times Less Than Steel." It depends on the epoxy resin being used to make the tubes.

    If I get impatient with waiting for that laser thermometer to arrive I may break down and start looking locally for another cheap one. If I find one I'll just send the amazon thermometer back for a refund. Maybe craigslist has something that will work. Why So Cheap? This whole DIY Carbon Fiber barrel wrapping project is a budget project. One of the main reasons I'm doing it is to find a way to not have to pay those incredibly high prices for a Carbon Fiber wrapped barrels from one of the few makers that sell them. Waiting for a cheap Chinese laser thermometer to arrive in the mail is not that big of a deal for me. I just hope you guys can hold out till it gets here because the more I work on this project, the more I believe it's actually going to work.

    HollowPoint
    Last edited by HollowPoint; 01-21-2020 at 08:24 PM.

  16. #36
    Boolit Master
    Join Date
    Apr 2009
    Location
    What the world calls "Global Warming", we in Arizona call "Summer Time."
    Posts
    2,123

    Interesting Email Correspondance While I Wait

    I'm still waiting for my laser thermometer to show up. I checked into it and if I'm really lucky it will arrive next week some time. Since I thought I'd be on hold until early or mid February waiting for this thermometer to arrive I agreed to help a friend out with his vintage pickup truck. What this means is that even if my laser thermometer does happen to get here next week, I'll be busy helping a friend; so, it will be a couple of days later till I can get back on this project.

    In the mean time, I thought I'd show you a bit of the email correspondence I've had with the guy over at RockWest Composites. I don't want it to come off appearing negative because this same guy has been gracious enough to reply to all of my email inquiries. That's far more than I can say about any of the half-dozen other composite companies I contacted. Besides that I'm sure that any testing that might have been done by his people, would have been done using high dollar methods done by highly paid people.

    This email correspondence is in regard to the Coefficient of Thermal Expansion numbers associated with the Carbon Fiber tubes I ordered from them. As I mentioned in my previous post, I'll be running the tests myself instead of paying to have them done. I'll be using a simple high-school-science testing method to arrive at the numbers I'm looking for. I'll be doing the same with the donor barrel as well. I just need that laser thermometer in order to get started with it.

    HollowPoint


    Hi Rylan:

    Our Carbon Fiber Barrel Wrapping project is moving along a bit faster now that I received the Carbon Fiber tubes I ordered from you guys. I’ve been doing some thermal expansion calculations on our donor rifle barrel in order to arrive at an optimum torque specification for torqueing down the Compression-Nut we’ll be using in our design. Once we were able to find the right coefficient numbers for the 416 Stainless Steel rifle barrel that part of our calculations went by fairly quickly.

    My reason for contacting you again was to ask if your engineers had worked up any thermal expansions coefficient numbers for the specific type of Carbon Fiber tubing I purchased from you. I’ve found various slightly differing coefficient numbers of Carbon Fiber composites online but it seems that the coefficient numbers that come up slightly different from one another depending on the type of resins used to bond the Carbon Fibers together.

    Are you able to supply a specific thermal expansion coefficient number for the type of Carbon Fiber Tube I purchased from RockWest Composites? Once I’ve worked up those numbers I’ll be able to go about assembling the barrel and installing it onto the rifle reciever for field testing.

    The tubing I purchased from you is as follows:

    TUBE - FILAMENT WOUND - UNSANDED - 0.625 X ~0.91 X 12 INCH - SOLD BY THE FOOT - AVAILABLE UP TO 108 INCHES
    Sku: 35045-U

    I’m hoping you’re able to reply sooner rather than later, otherwise we’ll have to move forward using generic Carbon Fiber coefficient numbers. I’d rather use the specific numbers associated with the Carbon Fiber Tubing I ordered from you. Thanks in advance.


    From: Rylan Hayes
    Sent: Monday, January 20, 2020 11:29 AM
    To: Tim M.
    Subject: RE: Searching for premade Carbon Fiber Tube but Clueless about which one

    CTE of composite tubing or carbon fiber more specifically is very LOW…

    We sell a very highly engineered tube product called ZTE that has guaranteed CTE values - https://www.rockwestcomposites.com/r...-carbon-tubing

    We might be able to test the SKU listed below in our thermal testing chamber but the cost might be $1k per test, we would not take this cost on ourselves unfortunately. I would also have to find out if we are able to test that specific diameter too. Currently we only test tubes @ 2” for one specific customer.


    Following is the simple test I'll be doing on both the donor barrel and the piece of CF tube I have left over from cutting that 24" length down. I'll be using a combination of digital calibers and dial indicators. One of my indicators measures at .0005 and the other is an .001 dial indicator. Also; I won't be using a Bunsen burner; I'll be using my heat gun.


  17. #37
    Boolit Master
    Join Date
    Apr 2009
    Location
    What the world calls "Global Warming", we in Arizona call "Summer Time."
    Posts
    2,123

    Out with the old and in with the new barrel

    I called my friend earlier today. This is the guy I mentioned about promising to help him out with his 1930 Model A pickup. It looks like he won't be able to do that work next week so that means I'll be free to pursue the work on my Carbon Fiber wrapped barrel; provided I get my recently ordered laser thermometer in the mail next week.

    I did check into that delivery again today and I was given an estimated delivery date of January 27th. It would be awesome if it got here on Monday. That would give me the rest of the week to play around with this project.

    I'd forgotten that since I would be utilizing an additional recoil-lug I'd have to work on the bedding to accept this added component. I did the bedding this morning. I'll be letting it sit till tomorrow some time as it fully cures. I assembled everything just hand-tightened in order to do that small amount of bedding. It's all fitting together nicely with no further messing around with inletting to fit the new Carbon Fiber barrel.

    Before taking my Tikka apart I re-weighed it to make sure I was giving you the correct information. As it was, wearing the 16" spiral fluted bull barrel I installed last year and with the scope in place and the magazine installed it weighed 8.3 pounds. That's pretty heavy for a rifle called a "Tikka-Lite" rifle. It was slightly lighter in its factory configuration. The bull barrel really put some weight on it.

    When I assembled this same rifle with the Carbon Fiber barrel in place wearing the same scope and magazine it weighed in at 6.11 pounds. So, the Carbon Fiber barrel shaved a couple of pounds off of the overall weight and it also did wonders for the balance of the gun. This equates to a not-so-Nose-Heavy rifle when I put the suppressor on.

    Some of you guys have already seen photos of this same Tikka-Lite rifle wearing the spiral fluted barrel but I decided to post one last photo of it as it was before I took it apart. Once I get the new CF barrel mounted it will give you a good comparison between the two. Also; I should mention that I spent about an hour this morning removing the tan colored paint that I'd painted it with when I installed the spiral fluted bull barrel. I'll leave the stock as it is for now but the barrel and receiver is stainless steel with the black Carbon Fiber tube as contrasting color.

    HollowPoint
    Attached Thumbnails Attached Thumbnails tikkasuppressed.jpg  

  18. #38
    Boolit Master
    Join Date
    Apr 2009
    Location
    What the world calls "Global Warming", we in Arizona call "Summer Time."
    Posts
    2,123
    My Laser Theremometer Showed Up Today!

    Perfect timing. I got the little bit of bedding I needed to do all finished up. I also did a slight mod to my action-wrench to hold the additional recoil lug centered as I screw everything down. Now all I need is some AAA batteries to get the darn thing to work. I guess I'll have to run to Harbor Freight first thing tomorrow morning.

    I hope to have the Thermal Expansion tests done and the gun assembled by the end of the week. Things are looking up.

    HollowPoint

  19. #39
    Boolit Master
    Join Date
    Apr 2009
    Location
    What the world calls "Global Warming", we in Arizona call "Summer Time."
    Posts
    2,123

    (CTE) Thermal Expansion Tests Worked (Kind Of)

    It actually did work but not by going with my original plan of using my heat-gun instead of a Bunsen burner or an open flame. The ambient temperature of the room and the barrel before applying any heat was 61 degrees F.

    I was only able to get the temperature of my donor barrel up to 126 degree F. It seemed that the column of heated air being shot out of my heat gun was hottest at the center of that column of air. The air at the periphery of that heated column of air tended to begin the cooling process as soon as I moved the heat gun in any direction.

    At 126 degrees the .0005" dial indicator measuring any outward expansion had still not moved. The digital calipers measuring the longitudinal expansion of my barrel started moving as soon as I got to about 75 or 80 degrees F.

    At the 126 degree mark my digital calibers had moved to .00065". It was painfully slow going. I couldn't get it past that level of heat so I decided to bite the bullet and break out my little propane flame thrower. I fired it up and lightly but rapidly skimmed that flame on the length of my barrel. I made just a few back and forth passes cause I really didn't want to apply an open flame to my donor barrel.

    With just five or six back and forth passes my digital calipers climbed to .022". My (.0005") dial indicator also moved to near the midway point between the Zero hash-mark and the hash-mark right next to it. I put the laser thermometer on it to see what the temperature was and it read 75 degree. I knew that couldn't be right. The instructions that came with this cheap little laser thermometer stated that shinny surfaces tended to give false readings. This had to be what was happening. Those same instructions also stated that if I was getting what appeared to be false readings that I could place a piece of masking tape or electrical tape on the surface of whatever it was I was measuring the temperature of and once that tape reached the same temperature as my barrel, the thermometer should then give accurate readings. The tape was meant to mitigate any reflection from a shiny surface.

    The electrical tape just melted right off and the adhesive on the back of the masking tape I tried didn't fare any better. My concern at that point was to NOT over heat the barrel. I don't think I even came close to doing that but I was not able to get the accurate readings I was wanting to get at the higher temperatures. It was a good enough indication to me that I could go ahead with original idea of how I'd go about torqueing down my Compression-Nut. I thought to myself after that fact that I should have just tied my melting-pot thermometer to the barrel and at least have gotten an indication of the barrel temp. I'll do that when I go to put it all together.

    I'll mount and head space the barrel. Then I'll put it back into my heating setup and when it gets to the same .022" length of expansion I'll then slip the Carbon Fiber Tube into place and torque my Compression-Nut just past the point of being snug. In my mind, that should give me a securely torqued down Compression-Nut with sufficient torque to compensate for this kind of expansion under my normal shooting range or hunting sessions.

    I had also planned on doing the same to the short length of left over Carbon Fiber tube I have. I also wanted to determine the CTE of that as well but if my laser thermometer won't give me anything resembling an accurate reading on my donor barrel I'm not really willing to shoot an open flame at the surface of that tube cause I'm pretty sure, without knowing for sure what temperature it's at I'll end up just ruining the tube.

    I took a few photos of this experiment and some video but I haven't had a chance to edit it down to be able to upload it here or to my Instagram account. I'll try to post those pics by the end of the week. I want to use the rest of this free week to get this thing all put together. I'd love to be able to take it to the range within the next couple of weeks.

    I'll be back.

    HollowPoint
    Last edited by HollowPoint; 01-28-2020 at 05:02 PM. Reason: Misspelling Bad grammar

  20. #40
    Boolit Master
    Join Date
    Apr 2009
    Location
    What the world calls "Global Warming", we in Arizona call "Summer Time."
    Posts
    2,123

    Still Photos Of My Thermal Expansion Tests

    Here are some still photos of the results I got from my thermal expansion testing. I went ahead and used my final linear expansion results to work backwards with my mathematical calculations and it appears that by using my propane torch I had managed to get my donor barrel to approximately 225 degrees Fahrenheit.

    I need to issue a correction here. In one of my previous post I stated that the Coefficient of Thermal Expansion numbers I'd found online for 416 stainless steel was, "6.5 X 10 -6. (that's six-point-five times ten to the negative six) That was incorrect. I had mistakenly mixed up the number "6.5." It was actually 5.6; and in this case, these particular CTE numbers were used if the temperatures went up into the 600 Fahrenheit range. I only went up into the low 200s so the numbers I used then were 5.5 X 10 -6.

    If that sounds confusing, I agree with you. Now you know why I suck at math. Anyway; I got the information I needed. Now I can proceed to mount the barrel, do the headspacing and then heat it up again in order to secure the Carbon Fiber tube into place.

    Here are those photos. I hope they make some kind of sense to you all. The short videos I made when I did these tests will take me a little bit longer to edit. I have to whittle them down to one minute apiece in order to upload them to my instagram account. I won't be uploading anything longer than that to my YouTube account until I've had a chance to do some field testing with the Carbon Fiber barrel in place.

    By the way, here is the link that I got my CTE numbers from. You may have to scroll down a bit to find the, "Mean Coefficient of Thermal Expansion" numbers but that's where I got my numbers.

    https://www.ulbrich.com/alloys/416-s...el-uns-s41600/

    HollowPoint
    Attached Thumbnails Attached Thumbnails CTE1.jpg   CTE2.jpg   CTE3.jpg   CTE4.jpg  
    Last edited by HollowPoint; 01-29-2020 at 03:42 PM. Reason: misspelling

Page 2 of 3 FirstFirst 123 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Abbreviations used in Reloading

BP Bronze Point IMR Improved Military Rifle PTD Pointed
BR Bench Rest M Magnum RN Round Nose
BT Boat Tail PL Power-Lokt SP Soft Point
C Compressed Charge PR Primer SPCL Soft Point "Core-Lokt"
HP Hollow Point PSPCL Pointed Soft Point "Core Lokt" C.O.L. Cartridge Overall Length
PSP Pointed Soft Point Spz Spitzer Point SBT Spitzer Boat Tail
LRN Lead Round Nose LWC Lead Wad Cutter LSWC Lead Semi Wad Cutter
GC Gas Check