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    • #32602
      1johnlb
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      Finally found you Gents. I lost track over the last 8-10 months, but life happens. Now back to burning powder.

      I must say nice looking forum, Tim.

      I’ve been reading and trying to catch up and came across one of Tim’s post about 6 xcb bullets that been designed. I know about the 30 and the 35 xcb’s but what calibers and where can I find the other 4 designs.

    • #32604
      Goodsteel
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      I have 4 with Accurate molds, (one of which may be scrapped) and two with NOE.

      The numbers for the accurate molds are:
      31-160G this is the TC version of the 30 XCB and it shoots quite well.
      36-220G This is the TC version of the 35 XCB.
      46-430G This is the first attempt at the 45XCB bullet, and it shoots very well indeed.
      46-415G This is the second attempt at the 45XCB. More testing is required, but so far it definitely plays second fiddle to Rev 1 and may be scrapped. Time will tell.

      Then of course there’s the NOE offerings of the long range XCB bullets
      310-165-FN or 30XCB. This is the originator and given it’s small diameter, it has been the most successful and truly the finest 30 caliber cast bullet I’ve ever shot.
      360-228-FN or 35XCB. This, like the 30XCB has been the finest 35 caliber bullet I have ever shot. I was able to achieve 2″ 10 shot groups at 100 yards at a speed of 2600FPS. Not as fast as the 30XCB, but I do not believe it is possible to shoot larger diameter bullets to the same speeds as the 30 caliber. I also believe that 30 caliber is the largest diameter bullet that can be used to hit the “second wall” (which is about 3100FPS and has nothing to do with the RPMTH) something else happens to a cast bullet at about 3000 FPS which I cannot explain. Smaller diameter bullets may be able to eke out a few more hundred FPS, but the limitations of available twist rates in 6mm, 6.5mm, 6.8mm and 7mm barrels makes this a very expensive endeavor to effectively test, therefore, 30 caliber is the practical choice for HV, long range, precision with cast bullets.

      Welcome to the forum! I’m glad you were able to find us!

    • #32607
      Larry Gibson
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      Welcome, glad you found this site.

      Larry Gibson

    • #32610
      popper
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      something else happens to a cast bullet at about 3000 FPS which I cannot explain Thoughts, ideas or evidence?

    • #32614
      kens
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      What about a little larger meplat style for hunting?
      XCB Hunter?
      A truncated cone with a bigger meplat??

    • #32615
      1johnlb
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      Dawg, I was hoping for maybe 8mm or 22 cal xcb, not that I don’t already have enough to play with. I barely got my 06 brass Fire formed when I stopped.

      I’m gonna find out if the cooper enriched alloy will push any faster. I picked up a another savage online over my break, a savage 16 short action magnum in 325 wsm. With the plans to find out how the surplus wc860 burns in the overbore case. If it will, I’m thinking of rebarreling to a slow twist Kreiger in 300 rsaum. I know it has a short case neck that may not be ideal for the 30xcb, but.

      I would appreciate feed back from anyone whose already gone here either with the wc860 or the 300 short mags and the xcb.

    • #32619
      Rattlesnake Charlie
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      There are many designs already out there for hunting. Many were exhaustively discussed on the other website. You failed to narrow your parameters, but if looking for .30 cal, the soup can in .311 has long been a standard.

      As for what what happens when cast bullets exceed 3,000 fps, their ain’t no easy answer. Stay tuned for in-depth discussions and real life results.

    • #32623
      Goodsteel
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      Check out the bullets I have listed at Accurate Molds. I linked them above, and that is exactly what they are.

    • #32626
      Goodsteel
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      popper;n13063 wrote: something else happens to a cast bullet at about 3000 FPS which I cannot explain Thoughts, ideas or evidence?

      All I know for sure is that groups open past 3000FPS and its not the RPMTH because using a slower twist barrel had zero effect. The bullets are not over spun, they are supposed to be stable, they are of superb quality……..and they fail. Long range results show linear dispersion is lost and the MOA becomes greater the further away the target is.

      Before the move, I was attempting to test and see if I could determine what’s going on by catching the bullets in a tunnel of wet sawdust. All this demonstrated was that at 2900FPS the bullets are being sized down almost to groove diameter. One theory I have thought about was that around 3000 the bullet is sized small enough that it starts to strip the rifling slightly, but I have no basis for that theory because this is literally something you can only see in holes shot through a target. At 3000FPS, the bullets are going so fast, they might as well be made of silly putty. I can’t even catch them without significant damage.
      That said, I don’t really have any desire to conquer this next wall. There is absolutely no reason to do so in my opinion, so I will continue to confine my testing to the sub 3000FPS speed window. There is a great shortage of practical experience hunting with HV cast bullets, and shooting them in a target setting. We made several very large leaps forward in the past two years, but it was all broad stroke. Right now, what little time I have is being spent on bullet design. I’m working with the larger calibers for the moment because they are harder to succeed with, and I figure a lesson learned from 45 caliber may be an edge with smaller calibers, and speed is the same as precision. One needs what the other does.

    • #32629
      Larry Gibson
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      As goodsteel mentions the bullets, all cast bullets with lube, get sized down more than groove diameter from the lube between the bullet and the barrel. I also have recovered XCBs and others that were sized down .003 -.005″. I’ve tested 13 different lubes at HV and find that 3 lubes provide accuracy at HV the best; Javelina (no longer made), 2500+ and 2700+. I had hopes that PCing the bullets would eliminate the lube and provide better performance at HV. So far my own testing and reports of others is not providing better results at truly HV.

      Before I discovered that “swaging down” I always wondered why I could achieve 2200 – 2300 fps with excellent hunting accuracy using a 323471 in a 10″ twist milsurp 8×57. I always attributed it to the Loverin style bullet. However that just never rang quite correct as the same Loverin style bullets in 30 cal wouldn’t perform the same in 10″ twist milsurp 30-06s. Now knowing the Mauser M98s in 8×57 had grooves .005 – .006″ deep verses the 30-06s .004″ deep grooves and that the bullets can swage down to less than the .004 deep grooves of the ’06 it’s logical that cast bullets don’t “strip” in the rifling as such. They just swage down at HV and the lands (rifling) just loses it’s grip on them. In the Mausers with their deeper grooves the lands still had a grip on the bullets.

      Another problem is the tin in a ternary alloy. The tin is eutectic and conducts heat far faster than either lead or antimony. I lose GCs and accuracy above 2950 fps in 90+ degree weather out here. In colder 50 – 70 degree weather I push to almost 3100 fps before losing the GCs. Recovered GCs reveal alloy soldered to the inside of the GC. Mtgun has been very successful at 2900 – 3100 fps with his own designed bullets cast of a binary shot alloy which has probably 3% +/- antimony and no tin. He also HTs them to a very high BHN. You can see his results posted on his lube test thread on CBA. A very fine test BTW.

      For hunting game (edible)with ternary alloyed cast bullets I’ve pushed the 311041 to 2500 – 2550 fps while maintaining excellent hunting accuracy out to 300 yards. At 2550 fps remaining velocity at 400 yards is 1450 fps so if accuracy holds it would still be effective on deer…..to 300 yards for sure. Since 99% of big game are shot on the short side of 300 yards (most are actually shot under 100 yards) a 14″ twist 26″ barreled 30 XCB or .308W would be just about the perfect 30 cal cast bullet hunting rifle.

      One of these days either I or someone else will pop a deer or pig with a 30 XCB at 2600 – 3000 fps (muzzle) and see how it does. Cast of #2 alloy I, based on my experiments into wet pack newsprint, I do not expect the bullet to shatter as the pundits, with no actual experience, predict. I would expect some expansion and perhaps some sloughing off of the expansion petals. Still, it just remains to be tested on actual game.

      Larry Gibson

    • #32631
      1johnlb
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      Has anyone tried pushing a copper enriched alloy up to 3000 +? I remember what happened with the elco and we attributed it’s failure to the lack of bearing surface, but copper enriched reach 3-400 fps faster in my test when compared with Larry’s and his alloy. Up until then I had been using a wdww +tin with almost the same velocities as Larry in my 308 1 in 14.

      Thinks Larry for heads-up on mtguns post. I’ll be searching for it tonight.

    • #32632
      1johnlb
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      Larry, you wouldn’t by chance have a link to Mtguns thread would you. I’m not very familiar with the cba forums site and a search comes up with bunny trails galore

    • #32633
      Goodsteel
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      1johnlb;n13089 wrote:

      Has anyone tried pushing a copper enriched alloy up to 3000 +? I remember what happened with the elco and we attributed it’s failure to the lack of bearing surface, but copper enriched reach 3-400 fps faster in my test when compared with Larry’s and his alloy. Up until then I had been using a wdww +tin with almost the same velocities as Larry in my 308 1 in 14.

      Thinks Larry for heads-up on mtguns post. I’ll be searching for it tonight.

      That is something I wonder as well. I have tried to persuade the experts on this to join here and help, but I think our test methods are a turn off. I see no reason why it cannot be done, especially if someone has put in the time to get everything working correctly, but it cannot be quantified if it is not demonstrated in a similar or more stringent fashion.
      I hope some will reconsider. I personally have no time to get into this, but I don’t poo poo it as a very possible means of shooting HV. Unfortunately, there are some things that may never be known. I’m happy that we have one way to get it done that has been thoroughly demonstrated and proven by many individuals, but my original hope for the XCB project was that there would be several methods brought to light and proven against each other for the education of all.

      I say all this simply to encourage you to jump on in (if you’re of a mind to) and demonstrate the validity of an alternate method! Just because we have one way to do this does not mean it’s the only way, and I will not allow a different method to be lambasted on this forum as long as the tests are conducted honestly and an attempt is made to be transparent about the actual effectiveness of this method, even if the learning process is ongoing.

    • #32634
      Larry Gibson
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      1johnlb;n13090 wrote: Larry, you wouldn’t by chance have a link to Mtguns thread would you. I’m not very familiar with the cba forums site and a search comes up with bunny trails galore

      Try

      http://www.castbulletassoc.org/forum/thread/13059-testing-bullet-lubes-at-3000-fps/

      Larry Gibson

    • #32635
      Larry Gibson
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      1johnlb;n13089 wrote:

      Has anyone tried pushing a copper enriched alloy up to 3000 +? I remember what happened with the elco and we attributed it’s failure to the lack of bearing surface, but copper enriched reach 3-400 fps faster in my test when compared with Larry’s and his alloy. Up until then I had been using a wdww +tin with almost the same velocities as Larry in my 308 1 in 14.

      Thinks Larry for heads-up on mtguns post. I’ll be searching for it tonight.

      About 5 – 7 years ago when I was first testing HV cast bullets in my Palma .308W with a 14″ twist I cast some 311466s with a babbitt laced alloy. I will have to locate the notes on how much babbitt was in the alloy. I pushed them successfully to 2677 fps and 43,800 psi. I show an accuracy load of 49 gr AA4350 at 2608 fps with 20 shots giving an SD of 11 fps and an ES of 40 fps. Accuracy was right at 2 moa for the 20 shots. I also tested the same babbitt alloy with 45 2.1s 311-180 bullet. pushing it to 2450 fps with 2.5 moa accuracy. The babbitt alloy gives a lot more shrinkage than #2 alloy so I’m not sure the 30 XCB mould would drop them large enough…..remains to be seen I guess. I’ve been wanting to cast some 311465s with the babbitt alloy to test in the 16″ twist 30×60. Just haven’t gotten to it……so much to do…..so little time……

      Larry Gibson

    • #32636
      kens
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      I experimented with copper enriched with little luck.
      In a manner that tin helps lead castability, I found copper enrich to be the opposite, it caused difficult casting.
      Also, with the temperatures that we all cast with our equipment, we can only see trace amounts of copper before the required temp goes skyrocket high for our equipment.
      We might see something like .1% or .2% copper but our equipment will never see 2.0% at our common temps.
      Just my own backyard findings.

    • #32638
      1johnlb
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      Larry Gibson;n13092 wrote:

      Try

      http://www.castbulletassoc.org/forum/thread/13059-testing-bullet-lubes-at-3000-fps/

      Larry Gibson

      Wow, Thanks Larry. Nice read. I’ll have to finish it a little later, looks like it turns into lube test.

      Any thoughts on how he got the 14″ twist up to 3000 fps. Maybe…… nose shaping….. nose shaping removed any voids or inconsistencies in his cast……. alloy…. bhn…….. caliber 7br…… heat treated alloy???

      I know it’s just a guess, until weeded out, but I value your Gents educated guess.

    • #32639
      1johnlb
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      kens;n13094 wrote: I experimented with copper enriched with little luck.
      In a manner that tin helps lead castability, I found copper enrich to be the opposite, it caused difficult casting.
      Also, with the temperatures that we all cast with our equipment, we can only see trace amounts of copper before the required temp goes skyrocket high for our equipment.
      We might see something like .1% or .2% copper but our equipment will never see 2.0% at our common temps.
      Just my own backyard findings.

      I’ve gotten my copper alloy to cast by upping the temp, casting paste for mold temp and adding more tin. Although, I don’t know my copper % I am able to someone repeat it in my alloy. I guess I need to find someone to analyze it for me. For the time being I’m just gonna see how hard it will push.

    • #32640
      popper
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      I’ve gone to 2% dents a bar of super hard and poured fine boolits. We’re talking m3 BPCRS is talking about nose design at long range and wobble angle causing MOA being expanded x 3 power. I’ve done 2700 from 1:10 308 , 1 1/2 MOA @ 100. 1/2% cu. PCd. 31-165a. Agree , not really interested in > 3000.

    • #32641
      kens
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      At 2% copper and it dents a bar of super hard, what was your casting temps? Did you cast with iron mold or alum ?

    • #32644
      1johnlb
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      Larry Gibson;n13092 wrote:

      Try

      http://www.castbulletassoc.org/forum…s-at-3000-fps/

      Larry Gibson

      That was the lube test although it looked a lot like yours, but that helped me find his alloy test. He lost 2 checks with the enhanced alloy at 3100+.

      Here’s the link for anyone else that wants to read it.

      http://www.castbulletassoc.org/forum…b-a6dd00109f9a

    • #32653
      bjornb
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      Dan over at Mountain Molds (mountainmolds.com) has done a bunch of very interesting testing at high velocity, both with a variation of alloys and also with different lubes. I just got one of his molds; the 120 gr spitzer in 30 cal. that I’ll be shooting in my 1:17 twist 30BR. I’m planning on posting results on this forum.

    • #32654
      popper
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      Al. From accurate.

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