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Thread: The Components of Going Faster

  1. #1
    Boolit Master

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    The Components of Going Faster

    We periodically hear of folks getting their cast rifle loads up to the mid-2000 fps range - - with accuracy.

    As most of us have figured out, the faster you go, the harder the process gets. Those that have figured it out, I'd like to get a dialog going on what was discovered along the way.

    Obviously, there's an alloy and a gas check component.

    There's a bullet shape and fit component.

    There's a lube component.

    There's a propellant choice component.

    For some, there may be a filler or base wad component.

    And yes, the gun itself.

    Tell us of your Mad Science.
    WWJMBD?

    In the Land of Oz, we cast with wheel weight and 2% Tin, Man.

  2. #2
    Boolit Master


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    Move your blind a hundred yards closer and get 100% success with 1700-1800 fps.

  3. #3
    Boolit Grand Master



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    Quote Originally Posted by Bigslug View Post
    We periodically hear of folks getting their cast rifle loads up to the mid-2000 fps range - - with accuracy.

    As most of us have figured out, the faster you go, the harder the process gets. Those that have figured it out, I'd like to get a dialog going on what was discovered along the way.

    Obviously, there's an alloy and a gas check component.

    There's a bullet shape and fit component.

    There's a lube component.

    There's a propellant choice component.

    For some, there may be a filler or base wad component.

    And yes, the gun itself.

    Tell us of your Mad Science.
    That is an excellent question. Unfortunately I have more questions than answers. I have been trying unsuccessfully to develop a 22 Hornet load for use on prairie dogs at near jacketed velocities. Larry Gibson with his 30 cal. XCB 16 twist barrel has achieved the best results I am aware of.

    https://castboolits.gunloads.com/sho...66#post5364266

    https://castboolits.gunloads.com/sho...-XCB-600-yards
    Last edited by M-Tecs; 03-31-2022 at 09:45 PM.
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  4. #4
    Boolit Grand Master Nobade's Avatar
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    I built a 30-06 specifically to test this. The trick is the 1:15 twist barrel, everything else is normal.
    Bullets are RCBS 30-165-SIL with normal gas checks.
    Lube is regular NRA 50-50
    Powder is whatever is slow enough to fill the case and be safe. Mostly 7383 or Win 780.
    Alloy is water quenched wheelweights.
    Accuracy holds around MOA, and it's easy to hit the 750 yard gong at the range if I hold for wind properly.

    This rifle also shoots #311410 hollowpointed and paper patched at over 3000 fps with good accuracy. I haven't tried a lot of different bullets in it but everything I have tried up to 175 grains shot very well. The slow twist makes all the difference from what I have seen.

  5. #5
    Boolit Master


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    I will be following this. I am particularly interested in maximum velocities attained with rifles shooting powder coated boolets.
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  6. #6
    Boolit Grand Master GhostHawk's Avatar
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    Twist rate and total speed will have a big impact on this.
    I truly believe we need to get back to basics.

    Get right with the Lord.
    Get back to the land.
    Get back to thinking like our forefathers thought.


    May the Lord bless you and keep you. May the Lord make His face to shine upon you and be gracious unto you
    and give you His peace. Let all of the earth – all of His creation – worship and praise His name! Make His
    praise glorious!

  7. #7
    Boolit Master

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    Remington model 700,factory standard twist 24” barrel, 30/06 caliber, Lee 190 grain rnfp boolit, cast of 50/50 ww-pure, 2% tin added, powder coated, heat treated at 425f for one hour, splashed in cold water after heat treated. Gas checked, and sized to .310”.
    Loaded with 58 grains of H4831, CCI 250 primer, boolit seated to crimp groove.
    At 87 yards( all the room I had) it shot 1.5” groups. Velocity was 2499 FPS average of 7 shots.
    Synthetic stock rifle........recoil was quite snappy to say the least!!!!!!!! ( I had flinchitis after the testing that’s for sure)
    I’ve shot the 300 and 400 yard gongs at the local range and it did well. Just my experience. ( I don’t load that boolit that heavy anymore).
    I firmly believe that you should only get treated by how you act, not by who or what you are!!

  8. #8
    Boolit Buddy
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    I cast mostly clip on weights. Boolits from a NOE 360 182 gr. WFN mold, PC'd and gas checked, loaded over max loads of LVR, shot from my H&R 35 Rem., group around 1.5" at 100 yards without leading. Not sure of velocity, but guessing around 2000 fps.

  9. #9
    Boolit Grand Master


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    I posted this some time back in response to a similar question. It may help, along with the responses above, to get you started.

    HV cast bullet loading

    Numerous others and I have worked bullets such as 311291, 311041 and several other cast bullets of the bore riding nose design every which way at higher velocity. Normally best accuracy comes in the 1700 – 1900 fps range as reported. That is within the RPM threshold for the 10” twist. You may or may not believe there is an RPM threshold but it’s what’s giving you larger groups as you increase the velocity and RPM above 1950 fps. Working different alloys, powders, sizing, GCs and lubes I was able to maintain 2 – 3 moa at 2200 – 2300 fps with the 311291 for consistent 10 shot groups at 100 yards. If you want to improve on that accuracy at or perhaps a little higher velocity I suggest you change bullet designs and pay particular attention to minute details when casting and loading.

    Bullet; with the ’06 the ideal cast bullet design is one that has minimal lube groove depth with enough lube for the length of barrel. It should have a short nose with minimal ogive of not more than caliber length. The bullet should have a bearing length from the beginning of the ogive to the base of the GC. That bearing length should just fit within from the base of the cartridge neck to the beginning of the leade. Two designs fill those requirements in most ’06 chambers; the Lyman Lovern design 311466 and the LBT 150 gr. With either bullet design moa accuracy with 3 -5 shots is obtained with proper casting, sizing and loading in the 2200 – 2300 fps range if the rifle/shooter are capable with a 10” twist rifle. With either cast bullet such accuracy (1 – 1.5 moa w/10 shot groups) can be obtained at 2400 – 2500 fps with a 12” twist and 2600 - 2700+ fps is possible with a 14” twist.

    [Note as of August 6, 2020; Since this was written we have learned a lot more about shooting naked and lubed cast bullets at HV, but the basics are here. There are also a few newer bullet designs available especially for HV shooting. I highly recommend the NOE 310-165-FN “30 XCB”. It has proven to be an excellent HV bullet but does extremely well at “normal” cast bullet velocities. PC’d and PP’d bullets add another dimension.]

    Alloy; I’ve found a strong yet malleable alloy of 18 – 22 BHN to work best. A hard brittle alloy with a high antimony content should be avoided. Lyman #2 alloy WQ’d out of the mould works very well up through 3000 fps.

    Cast bullets; they should be visually inspected under a magnifying glass for any defects. If using a multiple cavity mould they should be weight sorted if they do not weigh the same from each cavity. Weight sorting is most often done incorrectly for what is needed for HV cast bullet shooting. A search should find my posts on how weight sorting should be done.

    Gas Checks; bullet bases must be square and flat. If the sprue cut of is not even with the bullet base cut a sharp knife can cut it flat. GCs need to be soft so annealing them may be necessary if they are commercial. I use my own made from .015 brass shim stock. The GC should be a tight slip fit on the bullet shank. It should not be forced on and swage the flat bottom of the shank. [note; I have found the slip on GCs do not stay on with many HV loads and are detrimental to accuracy when they come off.] Thus I exclusively use Hornady crimp on GCs now. Even they can come off above 3000 fps but that’s outside the realm of this discussion. A GC seater (I use the Lyman on a 450 with a .311 H die) should be used to squarely seat the GC and crimped on in a separate step before sizing/lubing. I then lube in an H&I die of the same size as the “as cast” bullets. The GC’d and lubed bullets are then push sized the bullets through a Lee .310 or .311 sizer after.

    Bullet lubes; I’ve run multiple tests at HV with various commercial lubes. I consistently get the best accuracy with Javelina lube followed by 2500+. At high velocity/RPM the bullet lube needs to spin off very quickly and completely. Hard lubes do not and small chunks of lube sticking to one side of a cast bullet will unbalance it with inaccuracy being the result. Softer lubes work best at HV and I’ve yet to find one that betters Javelina.

    Cases; should be “match prepped”, well fire formed, neck sized with .002 neck tension, with uniform neck thickness.

    Powders; I’ve had best results with AA4350, RL19 and H4831SC. If loading density is below 80% I use a dacron filler.

    Primers; I’ve also ran numerous tests with different primers. “Soft” primers will lower velocity and RPM with these slower burning powders. Accuracy will appear to be better but it is the lower velocity/RPM from such. Load all to the same velocity/RPM and it’s hard to pick a “best” primer. I mostly use WLRs because that’s what I buy in bulk. Magnum level primers are not needed in the .308W or ’06 with these powders and give higher SD/ESs which isn’t good for accuracy.

    There you have my advise based on “been there, done that” numerous times. My best advise if you want jacketed bullet accuracy at jacketed bullet velocity in a .308W or ’06 is to get a quality 14” twist barrel 26”+ long and follow the advice I’ve given. You will be amazed at how easy accuracy at HV then comes with cast bullets, even with 311291 and 311041.

    Or, if you’re really interested you can build a HV cast bullet rifle. Here’s 11 shots (supposed to be 10 shot group but I lost track of the number of shots) in 5.9” at 600 yards from my 30x60 XCB shooting the 30 XCB cast bullet at 2900+ fps.

    Click image for larger version. 

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    Larry Gibson

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  10. #10
    Boolit Master Forrest r's Avatar
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    Myself, I haven't done a lot with hv cast bullets but I did put a bbl on a old canadian shooting team cil 950t. It's a puma rifle made by savage & I ended up putting a shilen replacement barrel on it. The receiver is the small shank along with the older style with the 4 3/4" hold down screw spacing. I wanted a long bbl but the tradeoff was it had to be lighter due to the smaller hold down screw spacing. The original bbl was 25" and had a puma contour (it was a canadian shooting team puma rifle). I ordered a 30" bbl with a standard puma contour, a .336 1.5* match chamber (308w) & a 1 in 14 twist.

    I actually wanted the bbl to use with the jacketed 155gr smk bullets. But it makes life interesting with cast bullets. Everything is a trade-off.

    The 308w cartridge isn't the best choice for case bullets with it's short neck. A lot of cast bullets have to seat deep to fit the throating which puts the base of the bullet in the boiler room. The long bbl does have a "whip" to it and does show vertical string when heating up from shooting with too fast of a cadence. But I do get a lot of velocity out of that 30" bbl and the 1 in 14 is a slow enough twist to play around with cast bullets doing up to 2700fps.

    Some interesting things I found with my very limited testing.
    The bullets nose makes a huge difference. These bullets were cast from a 2-cavity cramer mold with 1 cavity having the hp pin. This makes from an extremely strong nose on the cast bullet.
    [IMG][/IMG]

    Didn't matter what load/powder combo I tested, when pushed over 2200fps the sp bullet's groups always opened up compared to the flat nosed hp bullets. Typical groups
    [IMG][/IMG]

    Lube plays a huge roll in accuracy of hv cast bullets. The 1st testing I did with that new shilen bbl. I wanted to see if I could hold 10-shot groups to 2" @ 100yds and have the velocities in the +/- 2600fps range. Not really lofty goals for some casts but it was asking a lot out of me. Anyway I cast up a bunch off lee 160gr tl bullets and did head to head testing with traditional lube VS pc'd bullets. The traditonally lubed/sized bullets.
    [IMG][/IMG]
    The pc'd bullets.
    [IMG][/IMG]

    The pc'd bullets got higher velocities, I can only assume it's from the pc process itself. The heating of the bullet backing on the pc will actually soften/anneal the cast bullet. This makes the softer bullet expand/obturate/seal faster/better with the pressures of the loads being used making them more efficient.

    The other thing I got out of that initial testing was the 37gr load blew out with the traditional lube. I took the same lubed bullets and added 45/45/10 tumble lube to them and re-tested. Turns out I didn't have enough lube with the 1st test & it's was actually interesting to see that while I didn't have any leading. Accuracy went south when there's not enough lube.
    [IMG][/IMG]

    When I started pushing the pc'd bullets over 2700fps I started seeing this in that shilen bbl.
    [IMG][/IMG]

    Bore-tech eliminator took it right out. Others have said some pc colors do this while others don't. I'm using smoke's john deere green & again I simply gave the pc'd bullets a coat of 45/45/10 tumble lube and the black burn marks/streaking went away.

    I ran into an interesting issue with the xcb bullet. The lee bullet I use is similar in design to the xcb bullet. I did an initial test with the xcb bullet using 36gr and 37gr of h335. The results were terrible, had shotgun patterns on the targets. 2 years later I got the time to take a look at what was going on with that xcb bullet. So I re-tested and this time I decided to use 2 different gas checks. It just didn't make any since that the lee bullet would group and the xcb wouldn't. Same alloy/sizer/lube/ETC. In all my testing so far I used my home made al gas checks. This time I used my home made al gc's VS the store bought hornady copper gc's. Sure enough at lower velocities it didn't matter. Pump up the volume (velocity) with my home made al gc's on those xcb bullets and this is what I ended up with.
    [IMG][/IMG]

    Well there's 4 things I found with my limited testing/playing around with hv loads and cast bullets:
    The shape of the bullets nose plays a huge role in accuracy when pushed hard.
    The lube or more precisely the lack of lube will ruin your groups.
    Driving pc'd bullets over 2700fps (140,000rpms) caused the pc coating to leave burn marks in the bbl that a simple coating of tumble lube took care of.
    The difference in the material the gc's are made out of along with how hard/soft (annealed) they are affects accuracy when the bullets are pushed hard.

    If I were to buy a barrel strictly to use as a hv/cast bullet shooter I would buy another shilen bbl with the same .336/308w match chamber. But this 1 I would send my 1* throating reamer to them and have them cut the chamber and put a 1* leade in the throat. This would allow the bullets to be seated out further. The new bbl would be a 28" bull bbl with a 1 in 16 twist.

  11. #11
    Boolit Grand Master
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    Forrest r,

    I enjoy your posts and this one is an example of why. I look for honesty/reality and not a couple of "wallet" groups...or the thing that is a sure sign of BS..."When I do my part".

    One question...what was the traditional lube you used? Larry made a comment on his post about getting his best results with Javelina (as it sheds easily) and he had good success with 2500+.

    Again, good post!!!
    Don Verna


  12. #12
    Boolit Master

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    I'm pretty new to rifle casting, but I've been pushing a 150 gr right up to 2,000 with Lyman Moly lube and a GC. No problems so far.

  13. #13
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    My test rifle is a cutom M98 Mauser built by MBT Custom with a 14twist Krieger barrel chambered in 30-06XCB


    with the 30XCB bullet I have gotten great results with 2500+ and Carnauba Blue.




    Carnauba Blue gave very little variation for the cold bore first shot flier.
    The picture above is for 10 shots.

    I also seat my bullets to .005" off the lands instead of seating them into the lands.
    I don't know why this gives better results for me, but it does. I've tried it several times with various lubes and seating depths and .005" gives about 1/2 the group sizes of .010" off and seating into the lands.

    A note on pushing very high velocities, approaching 2900fps, the lube appears to collect at the front of the gas check and hydraulically swages the shank of the bullet down allowing the gas check to come off once it leaves the barrel.
    I plan on seeing if Al will cut me a 30XCB mold with the gas check shank a little shorter to minimize the gap between the gas check and the bottom driving band to see if this will have any effect. I will probably need another rifle with a 16" twist to push those velocities with any hope of accuracy.

  14. #14
    Boolit Master

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    Fantastic stuff so far guys!

    Regarding twist rate: I'm primarily launching this quest for off-the-shelf .30 caliber rifles, so 1-10 as the norm with 1-12" as the slowest is going to be my most likely playground. While the slower twist makes a great deal of sense, these are double-duty guns that will be shooting Barnes coppers as their hunting loads.

    Regarding bullet design: Do you have an opinion specifically on the structure and application of many small lube grooves vs. fewer large ones? I've had good results pushing the NOE/Ranch Dog 178 grain Tumble lube / Gas Check - which was specifically designed for the .308's neck configuration - in the low 2000's. It's a fantastic jug buster with it's big meplat, but not really designed for distance. My "go to" for the .30-06 has been the 311299 GC with Ben's Red, but the groups fall apart and the crown gets plated with alloy vapor as the speed increases. I have the .30 XCB mold, but the rifles it was bought for turned out to be a bust for other reasons, so it has not yet had its fair shake.

    Regarding propellants: Larry/Budzilla, I've had fantastic luck with H4831SC with jacketed, though it would not have occurred to me to use it to push cast. Do you think that slower burners like that are easier on the bullet structure, or somehow offer better obturation characteristics?

    Budzilla: I too have noted "stout" recoil when ramping things up with the 311299 - about a 200 grain bullet - in the .30-06. My pet theory is that it may have something to do with the fact that we're taking a system nominally designed for a .308 jacketed bullet and feeding it a .310"-311" projectile, typically cast of fairly stiff stuff for the purpose of achieving HV, and that a good bit of violence is going on in terms of chamber pressure as the bullet swages down. Maybe this is where a slower burning powder and a gentler "liftoff" may help?

    Regarding lubes: I have not yet ventured into the world of PC. Another tool in the toolbox, though it looks like success can be had with or without it. Forrest r - fascinating that you've tumble lubed OVER PC.

    QUESTION: What is your method for tumble lubing over the top of conventional lube? I've only dabbled in that briefly, but it seems like the TL solvents combined with the rolling around and banging into other bullets will dissolve and otherwise compromise the clean fill of the conventional lube groove fill. Otherwise, I absolutely agree that a full-bullet coating of ablative TL can only help with the process.

    ANOTHER QUESTION: Have any of the PC-ers experimented with conventional lube on top of a PC'd bullet? Since a lot of PC folks seem to be sizing after PC, this seems like it would be a natural progression that would serve to help keep all the hot gasses behind the bullet - - possibly serving the function of a base wad or filler without taking that actual step.

    And for Forrest r, STILL ANOTHER QUESTION: Absolutely fascinating, your results with the hollow-pointed Cramer. I agree that the hollow pointing might be adding significant rigidity to the front end of the bullet making it more resistant to nose slump, but MAYBE another factor is that it's moving the center of mass further back into the driving band section, making for a functionally shorter bullet length that's happier in your 14" twist?
    Last edited by Bigslug; 04-09-2022 at 07:00 PM.
    WWJMBD?

    In the Land of Oz, we cast with wheel weight and 2% Tin, Man.

  15. #15
    Boolit Master Forrest r's Avatar
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    I've been meaning to try different lubes, simply been using up the LBT Blue (hard) I have laying around.

  16. #16
    Boolit Master Forrest r's Avatar
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    Quote Originally Posted by Bigslug View Post
    Fantastic stuff so far guys!

    Regarding twist rate: I'm primarily launching this quest for off-the-shelf .30 caliber rifles, so 1-10 as the norm with 1-12" as the slowest is going to be my most likely playground. While the slower twist makes a great deal of sense, these are double-duty guns that will be shooting Barnes coppers as their hunting loads.

    Regarding bullet design: Do you have an opinion specifically on the structure and application of many small lube grooves vs. fewer large ones? I've had good results pushing the NOE/Ranch Dog 178 grain Tumble lube / Gas Check - which was specifically designed for the .308's neck configuration - in the low 2000's. It's a fantastic jug buster with it's big meplat, but not really designed for distance. My "go to" for the .30-06 has been the 311299 GC with Ben's Red, but the groups fall apart and the crown gets plated with alloy vapor as the speed increases. I have the .30 XCR mold, but the rifles it was bought for turned out to be a bust for other reasons, so it has not yet had its fair shake.

    Regarding propellants: Larry/Budzilla, I've had fantastic luck with H4831SC with jacketed, though it would not have occurred to me to use it to push cast. Do you think that slower burners like that are easier on the bullet structure, or somehow offer better obturation characteristics?

    Budzilla: I too have noted "stout" recoil when ramping things up with the 311299 - about a 200 grain bullet - in the .30-06. My pet theory is that it may have something to do with the fact that we're taking a system nominally designed for a .308 jacketed bullet and feeding it a .310"-311" projectile, typically cast of fairly stiff stuff for the purpose of achieving HV, and that a good bit of violence is going on in terms of chamber pressure as the bullet swages down. Maybe this is where a slower burning powder and a gentler "liftoff" may help?

    Regarding lubes: I have not yet ventured into the world of PC. Another tool in the toolbox, though it looks like success can be had with or without it. Forrest r - fascinating that you've tumble lubed OVER PC.

    QUESTION: What is your method for tumble lubing over the top of conventional lube? I've only dabbled in that briefly, but it seems like the TL solvents combined with the rolling around and banging into other bullets will dissolve and otherwise compromise the clean fill of the conventional lube groove fill. Otherwise, I absolutely agree that a full-bullet coating of ablative TL can only help with the process.

    ANOTHER QUESTION: Have any of the PC-ers experimented with conventional lube on top of a PC'd bullet? Since a lot of PC folks seem to be sizing after PC, this seems like it would be a natural progression that would serve to help keep all the hot gasses behind the bullet - - possibly serving the function of a base wad or filler without taking that actual step.

    And for Forrest r, STILL ANOTHER QUESTION: Absolutely fascinating, your results with the hollow-pointed Cramer. I agree that the hollow pointing might be adding significant rigidity to the front end of the bullet making it more resistant to nose slump, but MAYBE another factor is that it's moving the center of mass further back into the driving band section, making for a functionally shorter bullet length that's happier in your 14" twist?
    Larry would be the one to ask about pointed nosed bullets and their affects on accuracy. I remember reading posts about it when they were designing and testing the xcb bullet.

    I did testing with the MP hunter bullet
    [IMG][/IMG]

    It didn't matter if the bullet was a fn or a hp, both nose styles performed the same when tested head-to-head with the same loads. As you see from the picture above the nose of that hunter bullet fit the leade of my 308w chamber extremely well (rifling marks on loaded round).

    I also did testing with the MP silhouette bullet doing head to head testing with the solid nose VS hp's. Same thing, didn't matter.
    [IMG][/IMG]

    I didn't take a lot of pictures of the silhouette bullets, wasn't impressed and sold the mold after 2 or 3 test runs.

  17. #17
    Boolit Grand Master


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    "Regarding propellants: Larry/Budzilla, I've had fantastic luck with H4831SC with jacketed, though it would not have occurred to me to use it to push cast. Do you think that slower burners like that are easier on the bullet structure, or somehow offer better obturation characteristics?"

    Yes. The time pressure curves are slower. Thus, the acceleration rate is slower so there is less potential deformation of the bullet during acceleration.

    Long, pointy, unsupported nose are susceptible to canting in the bore because most have minimal groove diameter bearing surface.

    While I have pushed some bullets with bore riding noses [notably the 314299, the 311291 and the 311041] to 2300 - 2400 fps in my 14' twist .308W rifle holding 2 moa accuracy to 200 yards they are not the best designs for better accuracy at even higher velocity. The Lovern designs have always had a reputation for very good accuracy at higher velocities than other designs with pointed or bore riding noses. I got a 311466 mould (152 gr) Lovern Lyman mould and quickly found in my 1 - 10" and 1 - 12" twist 308W rifles it was indeed capable of holding accuracy at higher velocities. The question was, why? An analysis of the design showed it had a short non bearing nose, maximum groove diameter bearing length at 65 - 70 % and multiple shallower lube grooves. During this time I was posting the results her eon this forum and got a lot of adverse interest but also some positive interest. Tim Malcom (goodsteel) worked with Accurate molds and cam up with a 150 gr bullet that showed some promise. However, that bullet also had a longer than needed unsupported nose and one large lube groove. He sent me the moulds, I cast a bunch, and thoroughly tested them.

    Most designs, even ones of the last 20+ years, all have lube grooves based on the concepts of what was needed 100 years ago with the lubes available then. With the advent of beeswax/alox lubes in the '50s it was found most of those designs, including the modern ones with similar lune grooves, were "over lubed". Depending on the RPM, the excess lube will get thrown out of the grooves shortly after muzzle exit. If the lube comes off uneven the balance of the bullet is adversely affected. Also, the lube coming off is affected by the air traveling around the bullet and causes further wobble to the bullet.
    With modern lubes such as the NRA 50/50, 2500+, 2700+ and similar lubes all that lube in traditional designed lube grooves is not needed. What is needed is "just enough" lube and a soft lube so it will come off the bullet evenly after exiting the muzzle.

    Acceleration forces are tremendous when we accelerate a bullet from motionless to 2500 - 3000 fps in just 24 - 30" +/-. The smaller the unsupported smaller diameter of the bullet in the lube groove it is the greater the chance the alloy cannot withstand the acceleration with some collapsing or bending may occur. The deeper the lube groove the smaller the diameter of the bullet is in the lube groove and, thus, the greater that chance of the bullet collapsing or bending, especially with an unsupported or even a bore riding nose and minimal bearing surface.

    After thoroughly testing the Accurate XCB bullet in 10, 12 and the 14" twist 308W rifles I found it worked fairly well compared to other traditional bullets but no better than the 311466 Lovern bullet. Tim and I conflabbed with a couple others including Swede Nelson at NOE. I was one of the primary designers along with Tim, Swede and another of the 30 XCB bullet which was designed expressly for HV velocity. The design concepts were based on those factors which we believed would enhance accuracy at HV. The 310-165-FN "XCB" bullet design was finalized with a minimal nose for a decent BC. The front was tapered to fit the 30 XCB reamer [a 30-06 with a tight neck giving .001 clearance with a .310 bullet in neck trued cases with the bullet seated with the GC at the base of the neck. The throat (including free bore and leade) cut to fit the taper on the front of the 30 XCB bullet. The design maximized the groove bearing diameter at 65+ %. I consulted with Swede on the number of lube grooves to use, the width of them and the depth of them. Based on experiments with varied amount of lube in the 311466 bullet needed at HV in 28 - 30" barrels we came up with number and size of the grooves on the 30 XCB bullet to provide that amount of lune, no more and no less. It has proven to be a sufficient amount of lube for velocities up through 3300 fps.

    The cartridge for the bullet was originally supposed to be the 30x57 which is a short chambered 30-06. The case capacity was equal to the .308W but it had the body taper to feed well in Mausers and the neck length to hold the lube grooves of a 165 - 170 gr cast bullet in the neck. Bjorn and another did a bit of experimenting with the first 30x57 XCB rifles made. I also did a lot with the 30 XCB in my 26" M70 with 12" twist and my 27.7" barreled Palma 308W with a 14' twist. I found with the slower powders the case capacity of the .308W, and thus the 30x57 was just not quite enough to reach much above 2700 fps. I surmised, based on several thousand test rounds out of the 308W that a case with 100% load density of 52 - 54 gr AA4350 would be just right for 2900 - 3100 fps out of a 30" barrel. So, I ordered up a Broughton 32" barrel with a 16" twist and had it sent to Tim. I sent him a nice CZ-24 M98 action along with 3 formed cases for the 30x60 cartridge. They held (cases formed from Winchester 30-06 cases) 54 gr of AA4350 at 100% load density. Tim put the barrel on the action (he worked his usual magic truing everything up) and it came out at 31". I bedded the action when I got it back and began testing. The results were nothing but astounding. A search of this forum will find numerous posts detailing the results. However, here is a typical 100 yard 10 shot groups. I have also posted a sub moa 11 shot group shot at 600 yards. Additionally you can find the results fo a PD shoot i used the 30x60 on in Montana shooting them at 300 - 500 yards. After 3,000 + rounds testing i settled on 53 gr AA4350 which runs right at 2900+ fps at 48,000 +/- psi.

    Click image for larger version. 

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    The 30 XCB has also proven to be an excellent cast bullet at "normal" cast bullet velocities. The 30 XCB is my match bullet for CBA commercial rifle matches using my M70 Match rifle in 308W with 12" twist. Here are 2 five shot and a 10 shot groups for score on the CBA score target at 100 yards [upper left, right and bottom right. Thye bottom left is a sighter target) out of the M70 with the 30 XCB loaded over 2400. Velocity is 1850 fps.

    Click image for larger version. 

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    Larry Gibson

    “Deficient observation is merely a form of ignorance and responsible for the many morbid notions and foolish ideas prevailing.”
    ― Nikola Tesla

  18. #18
    Boolit Master

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    This is all very hope-inducing info Larry! I've got a 31" .30-06A1 with an 11" twist that likes 190gr SMK's and H4831SC, and the XCB mold is already on hand. . .

    My personal version of Ben's Red runs with a little higher beeswax concentration for added stiffness (yet still flows at room temp), but the supply is getting low and it's time to mix up or buy a new batch of. . .something. Any suggestions there?
    WWJMBD?

    In the Land of Oz, we cast with wheel weight and 2% Tin, Man.

  19. #19
    Boolit Grand Master


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    Larry Gibson

    “Deficient observation is merely a form of ignorance and responsible for the many morbid notions and foolish ideas prevailing.”
    ― Nikola Tesla

  20. #20
    Boolit Master

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    Cool! I found the 2500+ on the White Label site. (I'm SO glad that using a 4-digit number to designate a lube that's bound to be mentioned in discussions of 4-digit muzzle velocities isn't confusing AT ALL )

    Any direct links to Javelina? Assuming that's a home brew?
    WWJMBD?

    In the Land of Oz, we cast with wheel weight and 2% Tin, Man.

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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