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Post by Deleted on Dec 23, 2011 17:07:15 GMT -8
Guess I will have to post this again,,, I know alot of people heard us talking about the 243 LBC twist and all BHW makes is 10,,, Well as of yesterday Andy told me they are still making the 9 twist, but its the same as the 10 as far as not being able to stablize anything above 100s
The 95 Bergers are shooting Great out of my New 24 inch
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Post by Deleted on Dec 23, 2011 17:28:48 GMT -8
Is your 24" a 10 or a 9? thanks.
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Post by Deleted on Dec 23, 2011 17:34:32 GMT -8
Its a 9 twist, I called Andy yesterday after i opened the package and seen the 9 twist and he said they still making and selling them,,, I sighted it in yesterday with the 95 Berger and it shot great haven't had a chance to set up chono to check speeds,,, but I know at 400 + its out right wicked on a set of lungs ;D
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Post by Deleted on Dec 23, 2011 19:04:43 GMT -8
Impresive! You should be up there in the 2800's+ - 2900's I think those 95 grainers is as good as it gets w/o getting into the 8 twist. Bob Whitley's data is a great baseline www.6mmbr.com/gunweek068.html |
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Post by guncollector on Dec 24, 2011 11:44:34 GMT -8
Guess I will have to post this again,,, I know alot of people heard us talking about the 243 LBC twist and all BHW makes is 10,,, Well as of yesterday Andy told me they are still making the 9 twist, but its the same as the 10 as far as not being able to stablize anything above 100s The 95 Bergers are shooting Great out of my New 24 inch This raises a question in my mind. Why doesn't BHW make a 6mm barrel in an 8 twist that will stabilize the 105 gr. Amax and 107 gr. Matchking bullets? Those are two 6mm bullets I am most interested in shooting. |
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Post by Deleted on Dec 24, 2011 12:08:19 GMT -8
IMO, The 8 twist will buy you very little with the 105gr bullet vs. the 95gr bullet. Berger VLD 95gr. G1 is .486 vs. the 105gr G1 of .493
Are you looking for a 1000 shooter only? I am not convinced still the 6mm is the best way to do it. Those 26"are really long poles and pretty much dedicated to high power comp. Also if you are looking for the best bullets you are looking into 115gr bullets, 7 twist, and probably higher capacity, fire-forming and the hole nine yards. 24" is also big but more manageable. Personally I think with the 95gr and 22"-24" must be all one needs for hunting at long range and LR paper punching.
If you want to reach 1000yards strong look into at 6.5mm 130gr bullet and above at 2750fps min. Also a 6.5 123gr lapua scenar at 2800-2850 is an amazing 1000yards but you need a different case/upper though.
I think for the 243LBC the Berger 95gr VLD is as good as it gets. Very efficient little round, hard to beat on that category and with that simplicity.
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Post by GLSHOOTER on Dec 24, 2011 15:50:57 GMT -8
Guess I will have to post this again,,, I know alot of people heard us talking about the 243 LBC twist and all BHW makes is 10,,, Well as of yesterday Andy told me they are still making the 9 twist, but its the same as the 10 as far as not being able to stablize anything above 100s The 95 Bergers are shooting Great out of my New 24 inch This raises a question in my mind. Why doesn't BHW make a 6mm barrel in an 8 twist that will stabilize the 105 gr. Amax and 107 gr. Matchking bullets? Those are two 6mm bullets I am most interested in shooting. It could well be a marketing issue. The interest/demand for that twist might be relatively small. I have no real idea on that specifically but as most of the 6 MM stuff being produced by BHW is mostly small case size maybe the allure of the over 100 grain bullets is pretty low. I agree they are a great down range pill but unless you are up in the 243 LBC range you aren't going to have enough stuff in the boiler room to SAFELY move them out a a high velocity. My new 6X45 will be a 1:9 and that should handle what I want up to that fabled 95 grain Berger that we here about. It may well be my 600 yard single loaded bullet but for mag length the 87 grain Hornady might be the ticket unless a Berger 90 will fit too. Once I get a 243 LBC I'll be able to play more but there are some super under-100 bullets out here for game taking that I am familiar with and I won't feel cheated. Greg |
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Post by Deleted on Dec 24, 2011 20:51:31 GMT -8
1:9 Great choice. No need to single feed if you can find an old DPMS VLD mag. I am going away from the AI rounds and using this one to pop coyotes at 500 to 600 yards. They buck the wind much better. Also paper at 800 or 900 but dope is considerable so you might need a canted glass depending on your setup. Break speed is close to 1000 yds. What else one could ask for the little round that could. I think I can, I think I can.... huff... LOL!
6x45 LW50 R5 1:9 22" 95gr VLD Spread:2725 gr"95 G1:0.486 Zero: 200
Range (Yds) 0 100 200 300 400 500 600 700 800 900 1000 1100
Speed (fps) 2725 2532 2348 2173 2007 1849 1699 1558 1424 1299 N/A N/A
Energy (ft.lb) 1566 1352 1163 996 849 721 609 512 428 356
Drop (in) 0.00 2.46 10.35 24.55 46.14 76.40 116.88 169.50 236.61 321.14
Path (in) -1.50 1.97 0.00 -8.28 -23.95 -48.28 -82.84 -129.53 -190.72 -269.33
Elevn(MOA) -1.87 0.00 2.63 5.70 9.20 13.15 17.62 22.70 28.50
Windage(MOA) 0.35 0.72 1.11 1.54 2.00 2.50 3.04 3.62 4.27
Time(Sec) 0.00 0.11 0.24 0.37 0.51 0.67 0.84 1.02 1.22 1.45
Marry Christmas everyone!!! . ...Cannot wait to get up and open the new 6.5x47 lapua redding dies. They will be chugging along first thing in the morning.
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Post by knightdive on Dec 28, 2011 12:15:01 GMT -8
Is the 6mm generally really sensitive to twist rate? Or are we talking about the difference in fractions of MOA (well beyond my abilities)? In .223 1:9 may not be ideal but it seems to stabilize a wide range of different weights from with some examples working from 45-77 grains. .308 with a 1:12 twist seems to work just fine from 147 grain to 175 grain and some up to the 208 Amax's. From the sound of this thread the twist on 6mm barrels is only good for a narrow range of bullet lengths.
I know the P3 rifling doesn't deform the bullet as much as traditional rifling so greater consistency seems reasonable, but I didn't think it would have that great an influence in stabilizing different length bullets versus traditional rifling since the rotational velocity vs linear velocity wouldn't be any higher. Am I wrong on that?
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Post by Deleted on Dec 28, 2011 14:37:38 GMT -8
Is the 6mm generally really sensitive to twist rate? Or are we talking about the difference in fractions of MOA (well beyond my abilities)? In .223 1:9 may not be ideal but it seems to stabilize a wide range of different weights from with some examples working from 45-77 grains. .308 with a 1:12 twist seems to work just fine from 147 grain to 175 grain and some up to the 208 Amax's. From the sound of this thread the twist on 6mm barrels is only good for a narrow range of bullet lengths. I know the P3 rifling doesn't deform the bullet as much as traditional rifling so greater consistency seems reasonable, but I didn't think it would have that great an influence in stabilizing different length bullets versus traditional rifling since the rotational velocity vs linear velocity wouldn't be any higher. Am I wrong on that? It is really the opposite. A 1 in 10 will stabilize everything from a 55 to a 100 grain flat base, even a 95 grain VLD. I have seen some that will stabilize a 105 Amax. But that is the exception not the normal barrel. |
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Post by Deleted on Dec 28, 2011 15:04:44 GMT -8
I do follow the bullet manufacturer's recommendation.
Also the twist requirements are different at different speeds. Angular momentum wears out too so at long distance you might experience yaw that do not see in the first 200-300 yards. ..you will be able to measure that in the paper.
One thing is for sure, most folks do not need a pigs tail twist to enjoy awesome bullets. For long range I would stay in 1:9 and for a shorter, hunting, and faster burning one, I would probably stick to a light 18" 1:10 barrel with 75-90 grainers. 1:8 seems too much for any sensible 6x45 application.
At the moment 1:9 stabilizes all the solid coppers in 85 and 90gr I have tested. Also the Berger 95gr VLD and it doesn't get any better than that. I have been playing with the 105gr Amax and found that it shoots better out one 1:8 barrel but we will do more experimentation again when I get the 24" one in 1:9.
In any case the polygonal rifling seems to be helping with the kinetics of the angular momentum in flight. I am investigating that one but the study of drag in fluid dynamics, is complex math specially considering all other external ballistics variables.
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Post by knightdive on Dec 28, 2011 15:48:38 GMT -8
I do follow the bullet manufacturer's recommendation. Also the twist requirements are different at different speeds. Angular momentum wears out too so at long distance you might experience yaw that do not see in the first 200-300 yards. ..you will be able to measure that in the paper. One thing is for sure, most folks do not need a pigs tail twist to enjoy awesome bullets. For long range I would stay in 1:9 and for a shorter, hunting, and faster burning one, I would probably stick to a light 18" 1:10 barrel with 75-90 grainers. 1:8 seems too much for any sensible 6x45 application. At the moment 1:9 stabilizes all the solid coppers in 85 and 90gr I have tested. Also the Berger 95gr VLD and it doesn't get any better than that. I have been playing with the 105gr Amax and found that it shoots better out one 1:8 barrel but we will do more experimentation again when I get the 24" one in 1:9. In any case the polygonal rifling seems to be helping with the kinetics of the angular momentum in flight. I am investigating that one but the study of drag in fluid dynamics, is complex math specially considering all other external ballistics variables. If I'm reading the last part correctly, you're suggesting that the hard edged created by traditional rifling cause decay of angular momentum faster than the smooth edges of the polygonal rifling, right? I'll take your word for it on the math (I gave up on Calculus) but from a theoretical standpoint that does makes sense. I hadn't considered decay of angular momentum, but I have heard of bullet/twist combinations that weren't especially accurate at 100 yards but settled down nicely at 300 or further out which would suggest that loss of RPM or RPM vs. velocity has a definite impact on stability. The part about 1:9 stabilizing the solid copper 85's and 90's is a good bit of info for me, thanks for that. In CA we're pretty much limited to lead free bullets for hunting because apparently politicians think lead=candy to condors. An 18-20" light to medium contour barrel would make for a nice hunting rifle if I ever manage to unshakle myself from this desk long enough to go hunting. I've got 3 pig tags waiting for just such an opportunity (though I planned on using the .458 Socom for those) If the 1:10 will work from 55-100gn flat base, I'd have to believe the there's at least a chance that 107's would work in 1:9 If I happen to draw a the right one, or at least the 95 SMK's and VLD's should be right in the sweet spot. What would be the bottom end weight/length wise with a 1:9? |
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Post by AndyBHW on Dec 28, 2011 16:34:09 GMT -8
Good Evening everyone,
After a great deal of product testing we have found that the 1X10 twist is superior in performance to the 1X9 twist when it comes to stability. We have only done testing of the 1X9 from a 20" bbl and it was sub-par compared to the 1X10. We highly recommend the 1X10 twist because it is able to better handle the types of ammunition put into it. Therefore, while we can produce the 1X9 for this caliber, the 1X10 simply outperforms it, thus the 1X10 has become our default for this caliber.
In short, if you want better accuracy, stability and a wider variety of choices for your ammunition, we strongly recommend the 1X10 twist.
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Post by GLSHOOTER on Dec 28, 2011 16:42:45 GMT -8
Good Evening everyone, After a great deal of product testing we have found that the 1X10 twist is superior in performance to the 1X9 twist when it comes to stability. We have only done testing of the 1X9 from a 20" bbl and it was sub-par compared to the 1X10. We highly recommend the 1X10 twist because it is able to better handle the types of ammunition put into it. Therefore, while we can produce the 1X9 for this caliber, the 1X10 simply outperforms it, thus the 1X10 has become our default for this caliber. In short, if you want better accuracy, stability and a wider variety of choices for your ammunition, we strongly recommend the 1X10 twist. And a more truthful answer has never been written. Good going Andy. Greg |
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Post by Deleted on Dec 28, 2011 18:02:21 GMT -8
Yes, the sear cuts of enfield barreling have more impact in the dynamics in flight that one might believe they have.
I do have experience and lots of data with many other 6x45 barrels in 1:10, 1:9 and 1:8 rates but not poly barrels.
So there is nothing like comprehensive field testing and experience with multiple barrels and rates as others in this forum have done.
My next 6x45 barrel is going to be a light 18" in 1:10.
At the moment I need to see what I can do with the 24" 1:9 when it gets here. They are two complete different purposes. The 24" in 1:9 might be too much. but we will find out.
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