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Thread: Ruger drops all 6.8 rifles

  1. #41
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    What did they do to their brass?

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    Quote Originally Posted by rsilvers View Post
    What did they do to their brass?
    In addition to taking off Remington's name?



    They're using a different alloy.
    Last edited by lwrkeysfisher; 01-24-12 at 21:05.

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    Quote Originally Posted by rsilvers View Post
    I am saying that if 6.8 SPC-II chambers were in from the beginning, the typical factory load velocity would only be 30 fps more (about 1500 psi works out to about 30 fps).



    The 6.8x43 chamber has a tighter freebore than 6.8 SAAMI (which is already rather snug) - and it would be expected to raise pressures more than a SAAMI chamber raises pressures from its shorter throat.

    Sure one can argue that a tighter freebore helps accuracy, but one can also argue that the short throat of a SAAMI chamber helps accuracy.

    In summary, I would expect 6.8 SPC-II to have the least pressure, a SAAMI chamber to have more pressure, and a 6.8x43 chamber to have the most pressure.
    But you haven't ever tested any 6.8 have you? You relate that to 6.8 bullets that are over size which none are as a matter of fact most are .2765 and not even .277. We also know and have proven the chambers and rifling designs do make a huge differance in performance. One more thing if a reamer has a throat dia of .277 how big of a hole does it make?
    Last edited by constructor; 01-24-12 at 23:17.

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    Quote Originally Posted by constructor View Post
    But you haven't ever tested any 6.8 have you?
    I know the results of two tests - one by Western Powders ballistics lab, and the other by a SAAMI-member company. Both were done with professional instrumentation. A test barrel was made with a SAAMI chamber and tested for pressure with calibrated reference ammo - 55,000 psi. The chamber was then throated to SPC-II, and the pressure was re-tested with the same ammo. Pressure dropped by 1500 psi. New ammo was created with more powder to restore pressure back to 55,000 psi. The result - this new ammo in the SPC-II chamber was about 30 fps faster. I once posted the original emails from Western.

    The only reason why people think SPC-II ammo is so much faster is because the companies loading it are loading it over-pressure. If SPC-II became a SAAMI standard, it would not be loaded over pressure, and people would be disappointed to learn it was only 30 fps faster - and then wonder what all the fuss was about for the last 8 years.
    Last edited by rsilvers; 01-25-12 at 08:46.

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    Quote Originally Posted by rsilvers View Post
    I know the results of two tests - one by Western Powders ballistics lab, and the other by a SAAMI-member company. Both were done with professional instrumentation. A test barrel was made with a SAAMI chamber and tested for pressure with calibrated reference ammo - 55,000 psi. The chamber was then throated to SPC-II, and the pressure was re-tested with the same ammo. Pressure dropped by 1500 psi. New ammo was created with more powder to restore pressure back to 55,000 psi. The result - this new ammo in the SPC-II chamber was about 30 fps faster. I once posted the original emails from Western.

    The only reason why people think SPC-II ammo is so much faster is because the companies loading it are loading it over-pressure. If SPC-II became a SAAMI standard, it would not be loaded over pressure, and people would be disappointed to learn it was only 30 fps faster - and then wonder what all the fuss was about for the last 8 years.
    So a M1S barrel that blows primers at 2450fps is only 30fps slower than a high performance barrel that can shoot the same bullets at 2800fps??? That is why we changed the barrel specs, to get the BEST performance from the barrels. The SAAMI barrels made in 2006 were blowing primers with the best hanloads at 2450fps. Now we have barrels that will push 110gr projectiles to 2800fps without blowing primers. Are they high pressure? yes but I guess they were high pressure if they were blowing primers out of the SAAMI barrel too. Dang, thats about 500fps faster than the 300BLK isn't it?
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    Quote Originally Posted by constructor View Post
    So a M1S barrel that blows primers at 2450fps is only 30fps slower than a high performance barrel that can shoot the same bullets at 2800fps??? That is why we changed the barrel specs, to get the BEST performance from the barrels. The SAAMI barrels made in 2006 were blowing primers with the best hanloads at 2450fps. Now we have barrels that will push 110gr projectiles to 2800fps without blowing primers. Are they high pressure? yes but I guess they were high pressure if they were blowing primers out of the SAAMI barrel too. Dang, thats about 500fps faster than the 300BLK isn't it?
    The chamber is not the only component which effects pressures. It is very important to not have the bore cross-section area go below the SAAMI minimum of 0.0596 square inches.

    Regarding the Model-1 sales barrels - section one and put it on an optical comparator. Note the bore area before drawing conclusions about the throat dimensions being the main contributor to pressure.

    As for your comparison to 300 BLK - meaningless. I can make a barrel that will shoot hot hand-loads also.

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    Quote Originally Posted by SE_AK Hunter View Post
    .....Secondly Horrible accuracy. straight from Ruger's mouth, 6moa is acceptable accuracy from this rifle......
    No kidding. At least it is a small step in the right direction. When I was fighting with them to do something about my 77-22 that shot 6-8 inches at 50 yards the best I could get was "it meets Ruger accuracy specifications." "What are those specifications?" one might ask. They are a trade secret. I don't much care what Ruger does. I've got about all the big revolvers I want and outside of the LCR they don't make much of anything that interests me. The General Motors of the gun world.

    Quote Originally Posted by Jack-O View Post
    ......Just sayin... ruger is more prolific than you give it credit for
    I give them plenty of credit for being prolific. They have always preferred quantity to quality.

    Quote Originally Posted by SE_AK Hunter View Post
    ....Ruger said you had to send the gun back to them to service the dam piston......
    Wow. And again, I say...wow.
    Last edited by Suwannee Tim; 01-25-12 at 12:09.

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    Quote Originally Posted by rsilvers View Post
    The chamber is not the only component which effects pressures. It is very important to not have the bore cross-section area go below the SAAMI minimum of 0.0596 square inches.

    Regarding the Model-1 sales barrels - section one and put it on an optical comparator. Note the bore area before drawing conclusions about the throat dimensions being the main contributor to pressure.

    As for your comparison to 300 BLK - meaningless. I can make a barrel that will shoot hot hand-loads also.
    I thought you said the 8 twist didn't make any difference in pressure so your 8 twist barrels should be able to shoot hot handloads huh?
    But the guy that used a 300 in the 3 gun comp used a 12 twist hmmm wonder why?
    You will never get a 16" 300BLK to shoot 110gr bullets at 2800fps while not showing signs of high pressure.
    Didn't you say the 6.8x43 should show more pressure than a SAAMI chamber? Isn't that about throat dimensions, length and dia? Do you still think a reamer that is .277 dia will cut a .277 dia hole? So does that report you read mean that the tested throat diameter of the barrels were actually .308 and .309? ...and the reamers used to cut those throats were...?
    Getting confused between chamber dimensions and reamer dimensions?
    So what do you really know about the SAAMI and 6.8x43 chambers?
    If the bullet does not touch the sides of the throat and the bullet is fully engaged in the rifling before the base of the bullet leaves the case mouth allowing gases to leave the case still being trapped behind the bullet because the body of the bullet completely seals the bore how does the throat dia (a .0005 difference)make any difference in pressure?
    Now about freebore length. If the bullet can move forward an extra .050" before meeting the resistance of the lands that is similar to loading to a longer OAL making more case capacity and less pressure similar to Weatherbys rifles with a .250 freebore. He seemed to have good results getting more velocity with his rifles, about 200fps as I recall.
    Yeah I think I knew that bore area issue about 6 years before you tried to draw a 308 button with a diameter larger than .308. Lucky for you the button maker caught your mistake. Our goal was to make the 6.8 perform as well as it possibly can and we did. The chamber and rifling configuration makes less pressure, more velocity and is more accurate.
    Some times you have to think like a machinist to get the desired results out of machined parts rather than thinking like an inganear who believes everything can be figured out on paper. There is no substitute for hands on experience.
    As for Ruger and their 6.8, for whatever reason the mini isn't accurate if they want to sell them they need to fix it. Their piston 6.8 was expensive and a piston. Most of the 6.8 market is hunters, they just want to hunt and not spend extra money to do it. Ruger makes other fine products they just missed the mark this time.
    Last edited by constructor; 01-25-12 at 12:23.
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    Gentlemen,

    Lets keep the underhanded digs and personal or perceived personal attacks out of tech. If you can't do that, Staff will be happy to come in here and clean house. This site, unlike other large AR15 sites, won't stand for anything less than professional conduct. By posting on this site your agreeing to the code of conduct, so review it if you need to, otherwise its assumed you are complying with it when posting.

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    Quote Originally Posted by constructor View Post
    I thought you said the 8 twist didn't make any difference in pressure so your 8 twist barrels should be able to shoot hot handloads huh?
    Twist plays almost no role in pressure. This is why SAAMI only suggests twists, but does not have a maximum twist rate. When the M16 went from the 1:14 to 1:12 to 1:7 - some predicted pressure problems because M193 ammo was already hot on pressure. Those concerns turned out to be unfounded. Likewise, 308 has been compared with 1:12 to 1:8 and there were no pressure/velocity differences. 6.8 does not have special rules.

    Quote Originally Posted by constructor View Post
    But the guy that used a 300 in the 3 gun comp used a 12 twist hmmm wonder why?
    You mean this: http://bulletin.accurateshooter.com/...gun-nationals/

    They got good results with the selection blanks they had in stock for their 30 AS.

    Quote Originally Posted by constructor View Post
    You will never get a 16" 300BLK to shoot 110gr bullets at 2800fps while not showing signs of high pressure
    No doubt that 6.8 can reach higher velocities than 300 BLK. That is one of its advantages over 300 BLK.

    Quote Originally Posted by constructor View Post
    Didn't you say the 6.8x43 should show more pressure than a SAAMI chamber?
    Reducing the throat diameter to the minimum dimensions on the 6.8x43 DMR chamber would be expected to raise pressures more than the short-throat does on the SAAMI chamber.

    Quote Originally Posted by constructor View Post
    Isn't that about throat dimensions, length and dia? Do you still think a reamer that is .277 dia will cut a .277 dia hole?
    No, I don't think a 0.277 reamer will cut a 0.2770 hole, but I was always speaking about chamber dimensions, not reamer dimensions.

    Quote Originally Posted by constructor View Post
    So does that report you read mean that the tested throat diameter of the barrels were actually .308 and .309? ...and the reamers used to cut those throats were...?
    This is the report:

    http://www.border-barrels.com/articl...Consortium.htm

    It shows that tighter throats raise pressure, regardless of bullet size.

    Quote Originally Posted by constructor View Post
    So what do you really know about the SAAMI and 6.8x43 chambers?
    If the bullet does not touch the sides of the throat and the bullet is fully engaged in the rifling before the base of the bullet leaves the case mouth allowing gases to leave the case still being trapped behind the bullet because the body of the bullet completely seals the bore how does the throat dia (a .0005 difference)make any difference in pressure?
    See this article:

    http://www.border-barrels.com/articl...Consortium.htm

    Specifically the charts like this:



    Notice how with 30 caliber bullets there is a 600 BAR (8700 psi) spread between a 0.310 and a 0.307 throat. So each 0.001 smaller in throat diameter, the pressure went up about 2200 psi. Note that this does not require the bullet to be larger than the throat to be true.

    Another problem with tight freebores, especially for semi-autos - is that the bullets that are not perfectly concentric in the brass case will rub on the way in and increase the chance of failure to chamber.

    Quote Originally Posted by constructor View Post
    Now about freebore length. If the bullet can move forward an extra .050" before meeting the resistance of the lands that is similar to loading to a longer OAL making more case capacity and less pressure similar to Weatherbys rifles with a .250 freebore. He seemed to have good results getting more velocity with his rifles, about 200fps as I recall.
    Yes, the SPC-II and 6.8x43 chambers have that feature and it does reduce pressure - about 1000 psi typically (1500 max).

    From: Robert Silvers
    Sent: Thursday, July 14, 2011 5:06 PM
    To: Johan Loubser
    Subject: Re: Western Powders Ballistic lab

    Johan,

    Have you ever done a test where you take a 6.8 SPC SAAMI test barrel, measure velocity and pressure, then ream the same barrel to 6.8 SPC-II - and add more powder to match the pressure of the previous test, and then see how much extra velocity there is?

    Robert.


    ----------------------------------


    Robert,
    Yes we did exactly that and the difference was negligible as to be ignored ca 20-30Fps and <1000Psi.
    I know there is a lot of claims out there regarding this.
    Some apply the effects of other calibers (such as the 223Rem) with completely different expansion ratios to the 6.8SPC.
    The 6.98Spc is not sensitive to the slight changes in dimensions between the std and SPEC II.

    Regards
    Johan Loubser
    Ballistician
    Ramshot.Accurate.Powders
    From Art at SSA:
    I can not disagree with Bob's statement of only 1000 -1500 PSI reduction and <30 FPS increase with a given load and projectile with respect to the SAAMI VS the Spec II chamber
    The 0.001 smaller freebore of the 6.8x43 DMR would be expected to raise pressures about 2200 psi - so one could expect it to come out at about 600-1200 psi more pressure than a SAMMI chamber. The 6.8x43 chamber I would expect to come out about -100 to 400 psi ahead of the SAAMI chamber, and about 1100 psi behind the 6.8 SPC-II chamber.

    Quote Originally Posted by constructor View Post
    Yeah I think I knew that bore area issue about 6 years before you tried to draw a 308 button with a diameter larger than .308.
    308 grooves are 0.3080 +0.0020 -0.0000. So the groove diameter can be anywhere from 0.3080 to 0.3100 and be in spec.

    Quote Originally Posted by constructor View Post
    Lucky for you the button maker caught your mistake.
    I have never tried to make a 308 groove diameter that was oversized.

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    Quote Originally Posted by rsilvers View Post
    Twist plays almost no role in pressure. This is why SAAMI only suggests twists, but does not have a maximum twist rate. When the M16 went from the 1:14 to 1:12 to 1:7 - some predicted pressure problems because M193 ammo was already hot on pressure. Those concerns turned out to be unfounded. Likewise, 308 has been compared with 1:12 to 1:8 and there were no pressure/velocity differences. 6.8 does not have special rules.



    You mean this: http://bulletin.accurateshooter.com/...gun-nationals/

    They got good results with the selection blanks they had in stock for their 30 AS.



    No doubt that 6.8 can reach higher velocities than 300 BLK. That is one of its advantages over 300 BLK.



    Reducing the throat diameter to the minimum dimensions on the 6.8x43 DMR chamber would be expected to raise pressures more than the short-throat does on the SAAMI chamber.



    No, I don't think a 0.277 reamer will cut a 0.2770 hole, but I was always speaking about chamber dimensions, not reamer dimensions.



    This is the report:

    http://www.border-barrels.com/articl...Consortium.htm

    It shows that tighter throats raise pressure, regardless of bullet size.



    See this article:

    http://www.border-barrels.com/articl...Consortium.htm

    Specifically the charts like this:



    Notice how with 30 caliber bullets there is a 600 BAR (8700 psi) spread between a 0.310 and a 0.307 throat. So each 0.001 smaller in throat diameter, the pressure went up about 2200 psi. Note that this does not require the bullet to be larger than the throat to be true.

    Another problem with tight freebores, especially for semi-autos - is that the bullets that are not perfectly concentric in the brass case will rub on the way in and increase the chance of failure to chamber.



    Yes, the SPC-II and 6.8x43 chambers have that feature and it does reduce pressure - about 1000 psi typically (1500 max).



    From Art at SSA:


    The 0.001 smaller freebore of the 6.8x43 DMR would be expected to raise pressures about 2200 psi - so one could expect it to come out at about 600-1200 psi more pressure than a SAMMI chamber. The 6.8x43 chamber I would expect to come out about -100 to 400 psi ahead of the SAAMI chamber, and about 1100 psi behind the 6.8 SPC-II chamber.



    308 grooves are 0.3080 +0.0020 -0.0000. So the groove diameter can be anywhere from 0.3080 to 0.3100 and be in spec.



    I have never tried to make a 308 groove diameter that was oversized.
    I like that "I would expect" statement...real conclusive there.
    You posted on 68 forums that you did send a 308 button design in larger in dia than .308 trying to keep the bore size correct and the button manufacturer called you up and asked if you really wanted to do that.
    This whole "design a better spec 6.8 barrel" started because SSAs ammo was blowing primers. They loaded some X-treme copper plated(like a TMJ pistol bullet, not a jacketed bullet) bullets that were swelling in the cone and throat area of the chambers. The SAAMI chambers had a sharp edge that would shave off a copper ring as the swollen bullets moved forward into the barrel. Those shavings would build up just ahead of the case mouth causing a restriction and blow the primers. The story goes that at a large mil test session primers were blowing and Barrett blew his lid. Shortly after, maybe Jan 06 I talked to Art about the issues I had seen in some 6.8 barrels. He said they had started to ream the throat .050 deeper to solve the problem. I picked up a chamber drawing from PTG that showed the chambers had a 80 degree cone angle which made a pretty sharp edge to shave the copper rings. I redesigned that chamber into the DMR which corrected that sharp angle and was a true match chamber. In 07 and 08 I cut about 300 stainless Pac Nor and Hart barrels with that chamber design.
    Those barrels were pushing the 85gr Barnes to 3200fps and 110gr bullets to 2800fps with no pressure signs. No other barrel made could do that. Art and I went hog hunting in Texas in 07, Kotonics and my barrels were the only ones that would shoot SSAs combat loads without showing swipes. In 08 5 of us got together again with several different brands of barrels to test them against each other in real world tests. Tim W wrote the results of that test session and published it as the 2008 performance report. We compared real SSA ammo in real 6.8 barrels made by several companies and compared the results. Even an idiot could see the difference between the case conditions and they matched the pressures recorded with the pressure trace system.
    In 2009 SSA produced some ammo with .309 diameter necks when the max spec was .306. It caused some major over pressure problems because the bullets were being clamped in the case by the chamber neck but it was an ammo isssue not a chamber issue. It effected me more than others because I wasn't using a sloppy chamber. So in 09 I revised the chamber again to work with SSAs oversized ammo, that is the 6.8x43 chamber I use now. The neck is tapered to match the SSA ammo because their necks are thicker at the bottom than the top. The SPCII chamber is actually smaller than the 6.8x43 at the base of the neck.
    You keep posting that thing about the 308 over sized bullets and potential problems and trying to relate that to my 6.8x43 chamber for obvious reasons. What you don't know is the actual size of the chambers so again you are thinking and talking about stuff you have never seen, measured or tested. You're putting out info about 308 barrels and oversized bullets and all kinds of stuff that has nothng to do with the real world 6.8 bullets and barrels.
    Going all over the internet to find articles that support your cause doesn't prove anything. I can find articles that say Elvis is alive.
    We don't have a few hundred barrels out there we have several thousands being used by people, DEA, Seals Leo and wardens that can say without a doubt they work better than SAAMI barrels and are usually 60-80fps faster than 11 twist 4 groove SPCII barrels. We took over a contract because a big companies SPCII barrels weren't reliable. You, someone that has never tested the 6.8 saying there is only 30fps difference and what were we arguing about for 8 years it's all a guess on your part, real people shooting real 6.8s with real bullets know the difference.
    If someone made a SAAMI chambered barrel with my 5R rifling it would be better and show less pressure than a SAAMI barrel with 6 grooves. If someone rechambers a SAAMI barrel to the SPCII chamber it makes a difference. If the chamber and rifling is changed it makes a huge difference. Consumers see it, that is what they want to buy. Ruger wasn't selling it so their sales were slow, if something I have moves slow and something else moves fast I would cut it too.
    Business is about turning money the more times you turn it in a year the more proffit you make. There are several companies out there that sell hundreds of 5.56s a day. DPMS says they sell 10,000 rifles a month. If I were them I would not sell anything else if that was the fastest way for me to turn money. It's about making money not which caliber it is.
    BTW I don't think you or Art either one know the DMR chamber no longer exist except in the custom match barrels I manufactured in 07 and 08.
    I can't figure out why either of you are still talking about it.
    Last edited by constructor; 01-26-12 at 09:52.
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    Quote Originally Posted by Microalign View Post
    True. I am just wondering if this is just a series of events that is leading to the possible death of the catridge. Will more and more manufacturers stop supporting the cartridge? I suppose it won't matter too much if I reload, but the 6.8 from my perspective seems to be losing popularity rather than gaining. I see even less support for the Grendel.
    We're just a small shop but gaining about $280,000 in sales a year.
    They can't supply enough barrels for us to keep them in stock, we run out before they can get the next batch made and delivered. Hornady said their sales of 6.8 are increasing and they are planning a GMX bullet to add to the line.
    S&B were charging $28 a box for ammo and using the least accurate bullet so who cares if they drop the 6.8. Hornady and SSA will pick up the slack and if Tula, PCP and PPU get into it there will be plenty.
    Just look at all of the bullets that have been added to the .277 line up in the last 4 years. The 6.8 isn't going anywhere but up.
    I think #33 is actually a Sierra 130gr SPBT.

    Available factory ammo



    6.8 SPC
    BVAC--------115gr SMK
    ---------------110 Vmax
    Corbon------110 TTSX
    --------------115 SMK
    --------------115 subsonic
    DoubleTap-----95gr Barnes TTSX
    ---------------110 Vmax
    ---------------115 FMJ
    ---------------110TTSX
    ---------------110 OTM
    Hornady-----110 Vmax
    ---------------110 OTM
    ----------------120SST
    Rem.---------115 FMJ
    ---------------115 HPBT
    --------------115 corelokt
    --------------115SMK

    SSA------------85 TSX------------SSAs loads available in Commercial and Tactical velocities
    ----------------90 TNT
    -----------------95TTSX
    ----------------95 frangable
    ----------------97 AP
    ----------------100 Nosler Accubond
    ----------------110 Nosler Accubond
    ----------------110 Sierra Pro hunter
    ----------------110 TTSX
    ----------------115 SMK
    Wilson Combat---95gr TTSX
    Last edited by constructor; 01-30-12 at 16:20.
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    Ooh!... I designed #28!

    work in progress tho..

    you should see the 762x54 projectile!!
    Last edited by Jack-O; 01-26-12 at 01:21.
    My capacity for self deception is exceeded only by yours.

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    Quote Originally Posted by Jack-O View Post
    Ooh!... I designed #28!

    work in progress tho..

    you should see the 762x54 projectile!!
    You should have run with that 120 back when you sent them to me.
    If you added a small boattail it could become popular. I don't think the Berger 140 will work that well. Crank up a thread on 68forums and see what they think. IMO leave it the same length and just chamfer the bottom, it may end up at 117 or something but look at the photo, it's shorter than the 120SST so better case capacity and longer than the 115s for a better BC.
    Last edited by constructor; 01-26-12 at 01:38.
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    Just a reminder to what COLD stated earlier. Please keep in mind that some of you are addressing people who are very active and working in the industry and may have alot more knowledge than what you read on the internet.





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    Quote Originally Posted by constructor View Post
    There is no substitute for hands on experience.
    I have no dog in this hunt (other than trying to decide between the two calibers), but this is a truism I have found in many of my scientific endeavors as a researcher. What we "think" and what we "find" are often two very different things whether it is rifle specs or semiconductors.

    A good researcher is also a very good mechanic (and vice versa--good mechanics make good researchers--I learned at least as much from my techs as I did my "mentors")

    Now back to our regularly scheduled programming...

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    I am not writing off the 6.8, but I am cautious to get into it. It appears that PRI mags are of the best quality, and I have been looking at DD's new 6.8 SPCII barrel with a 1:11" twist. I plan on sticking with a 16" barrel. Are any of you guys able to run 130gr bullets out of such a setup?

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    Quote Originally Posted by Microalign View Post
    I am not writing off the 6.8, but I am cautious to get into it. It appears that PRI mags are of the best quality, and I have been looking at DD's new 6.8 SPCII barrel with a 1:11" twist. I plan on sticking with a 16" barrel. Are any of you guys able to run 130gr bullets out of such a setup?
    We tested 130gr Speer and Sierra in 06 they work fine in as slow as a 12 twist, the Noslers are too long to fit in the mag same with the CTs.
    Bunch of load data over on 68forums.com we can get 2450-2500fps out of our 5R barrels using 30gr H335, CCI41 primers 2.3" OAL, work up to that not all barrels will handle it.
    Last edited by constructor; 01-26-12 at 10:42.
    NAFTA and greed is killing this country. Support America, buy American and put Americans back to work
    ARP ... SIX5... Nexgen 308

  19. #59
    Join Date
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    Quote Originally Posted by constructor View Post
    You should have run with that 120 back when you sent them to me.
    If you added a small boattail it could become popular. I don't think the Berger 140 will work that well. Crank up a thread on 68forums and see what they think. IMO leave it the same length and just chamfer the bottom, it may end up at 117 or something but look at the photo, it's shorter than the 120SST so better case capacity and longer than the 115s for a better BC.
    yep, planned on reducing the ogive a wee bit and giving it a nice boat tail. BT length will depend more on stability that raw BC I think. if I can get a good stable bullet then BC wont matter as much. that thing is gonna expand like crazy too.

    actually when I saw Hornady's 120gr I thought they had nailed it, but now looking at it again I see there is a little room for some tweaking.

    Still waiting on my brass guy to get his equipment in place then we might have a new brass manufacturer too!! I'll also have another manufacturer or two to add to the list.

    lots of stuff working quietly behind the internets back
    Last edited by Jack-O; 01-26-12 at 11:51.
    My capacity for self deception is exceeded only by yours.

  20. #60
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    Quote Originally Posted by Jack-O View Post
    yep, planned on reducing the ogive a wee bit and giving it a nice boat tail. BT length will depend more on stability that raw BC I think. if I can get a good stable bullet then BC wont matter as much. that thing is gonna expand like crazy too.

    actually when I saw Hornady's 120gr I thought they had nailed it, but now looking at it again I see there is a little room for some tweaking.

    Still waiting on my brass guy to get his equipment in place then we might have a new brass manufacturer too!! I'll also have another manufacturer or two to add to the list,

    lots of stuff working quietly behind the internets back
    I don't like the secant ogives Hornady uses but... their 110hpbt is very accurate. There are a bunch of guys wanting a better long range bullet, we're doing a 20" 5R barrel so keep us informed.
    Last edited by constructor; 01-26-12 at 12:27.
    NAFTA and greed is killing this country. Support America, buy American and put Americans back to work
    ARP ... SIX5... Nexgen 308

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