Some info please. 6.5 creedmoor

[adccoyote428]

Ok I would like a ball park figure on case capaxity of Nosler 6.5 Creedmoor brass of possible? Less than Hornady I am assuming? Also if possible a QL request for the 129 LR AccuBond using 129 Nosler LR accubonds and Nosler brass. H-4350 powder and H-4831 SC if possible. Thanks in advance,

The things I am looking at is bullet stability, I has some of the 142 LR AB's and out to 200 they shoot pretty well, but putting them in a stability calculator it seems at Creedmoor speeds 2680-2710 that long of a bullet even in 8 twist is marginal stabilized with these calculators? I am thinking going back to the 129 LR AB would afford me much better stability numbers over a wider range of elevations and tempatures?

Any thoughts on this would be greatly appreciated.

 

[Wyo7200]

142 on top and 129 on bottom. I think they stabilize pretty well if 1.5 is the magic targeted number....

I don't have any Nosler brass or else I'd help you with QL.

Midwayusa has a sweet deal on the 129's right now...

 

[adccoyote428]

Hey thanks for that chart and I see my suspicions where somewhat on track. The 142 states a twist of 1-7 for the 142 and the 129's 1-8 and a bit better stability. Also I doubt I could get to 2,800 FPS with a 6.5 Creedmoor shooting the 142's. My gun is a 1-8 savage.

I just ordered today 2 boxes of the 129's from Midway and they shipped them today, I am in state so will have them fast.

Thanks on the QL I understand and hopefully someone can plug in the data.

Thanks agin for the chart.

 

[Wyo7200]

My pleasure.

I have savage mod 10 hunter max-1 24" barrel and have chrono'ed the 142's above with R17 just kissing that 2800 fps- Though I can't remember what model or length you have. I love that R17, but get frustrated with its sensitivity.

Those calcs I have are from accurate shooter and miller stability equations. I got tired of entering the data into multiple sites so I created my own excel workbook with the formulas. AS(?) said with the recommended twist rate, you can be + or - two and still be ok in theory.

 

[Wyo7200]

According to the primers, brass, rifle bolt and QL, I'm operating at a safe level.

Chrono logs:


Group:

 

[adccoyote428]

Anyone have QL for the 129 using H4350 with Nosler brass and OAL of 2.840

In 6.5 Creedmoor?

 

[DrMike]

Cartridge          : 6.5 Creedmoor Hornady
Bullet             : .264, 129, Nosler AccuBond LR 58943 G7
Useable Case Capaci: 48.113 grain H2O = 3.124 cm³
Cartridge O.A.L. L6: 2.840 inch = 72.14 mm
Barrel Length      : 224.0 inch = 5689.6 mm
Powder             : Hodgdon H4350

Predicted data by increasing and decreasing the given charge,
incremented in steps of 2.0% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !

Step    Fill. Charge   Vel.  Energy   Pmax   Pmuz  Prop.Burnt B_Time
 %       %    Grains   fps   ft.lbs    psi    psi      %        ms

-20.0   83    35.92   3345    3205   32663    589    100.0    6.997
-18.0   85    36.82   3401    3313   34818    593    100.0    6.856
-16.0   87    37.72   3455    3420   37106    597    100.0    6.722
-14.0   89    38.61   3509    3526   39556    601    100.0    6.590
-12.0   91    39.51   3561    3632   42140    605    100.0    6.461
-10.0   93    40.41   3612    3737   44870    608    100.0    6.340
-08.0   95    41.31   3663    3842   47773    612    100.0    6.223
-06.0   97    42.21   3712    3947   50866    616    100.0    6.112
-04.0   99    43.10   3761    4052   54161    619    100.0    6.005  ! Near Maximum !
-02.0  101    44.00   3809    4156   57675    623    100.0    5.902  ! Near Maximum !
+00.0  103    44.90   3857    4261   61424    626    100.0    5.803  ! Near Maximum !
+02.0  106    45.80   3904    4365   65428    629    100.0    5.708  !DANGEROUS LOAD-DO NOT USE!
+04.0  108    46.70   3950    4470   69708    632    100.0    5.616  !DANGEROUS LOAD-DO NOT USE!
+06.0  110    47.59   3996    4575   74288    635    100.0    5.528  !DANGEROUS LOAD-DO NOT USE!
+08.0  112    48.49   4042    4679   79195    637    100.0    5.443  !DANGEROUS LOAD-DO NOT USE!
+10.0  114    49.39   4087    4784   84458    639    100.0    5.360  !DANGEROUS LOAD-DO NOT USE!

Results caused by ± 10% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 10% relative to nominal value:
+Ba    103    44.90   3911    4380   72277    597    100.0    5.635  !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba    103    44.90   3771    4073   50770    671    100.0    6.054

 

[wildgene]

...dang, I wonder what kinda MV's you'ld get outta a 250" barrel??? :shock: :roll: :mrgreen:

 

[DrMike]

Good catch, Gene, Here's the answer.

Cartridge          : 6.5 Creedmoor Hornady
Bullet             : .264, 129, Nosler AccuBond LR 58943 G7
Useable Case Capaci: 47.572 grain H2O = 3.089 cm³
Cartridge O.A.L. L6: 2.800 inch = 71.12 mm
Barrel Length      : 250.0 inch = 6350.0 mm
Powder             : Hodgdon H4350

Predicted data by increasing and decreasing the given charge,
incremented in steps of 2.0% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !

Step    Fill. Charge   Vel.  Energy   Pmax   Pmuz  Prop.Burnt B_Time
 %       %    Grains   fps   ft.lbs    psi    psi      %        ms

-20.0   84    35.92   3384    3280   33249    511    100.0    7.616
-18.0   86    36.82   3439    3389   35460    515    100.0    7.465
-16.0   88    37.72   3494    3496   37821    518    100.0    7.320
-14.0   90    38.61   3547    3603   40336    522    100.0    7.177
-12.0   92    39.51   3599    3710   42998    525    100.0    7.041
-10.0   94    40.41   3650    3816   45813    528    100.0    6.911
-08.0   96    41.31   3700    3922   48811    531    100.0    6.786
-06.0   98    42.21   3750    4028   52007    535    100.0    6.667
-04.0  100    43.10   3799    4133   55417    537    100.0    6.553  ! Near Maximum !
-02.0  103    44.00   3847    4239   59057    540    100.0    6.443  ! Near Maximum !
+00.0  105    44.90   3894    4344   62946    543    100.0    6.337  ! Near Maximum !
+02.0  107    45.80   3941    4450   67104    545    100.0    6.236  !DANGEROUS LOAD-DO NOT USE!
+04.0  109    46.70   3988    4555   71556    548    100.0    6.138  !DANGEROUS LOAD-DO NOT USE!
+06.0  111    47.59   4034    4661   76326    550    100.0    6.043  !DANGEROUS LOAD-DO NOT USE!
+08.0  113    48.49   4079    4766   81445    552    100.0    5.952  !DANGEROUS LOAD-DO NOT USE!
+10.0  115    49.39   4124    4872   86946    554    100.0    5.864  !DANGEROUS LOAD-DO NOT USE!

Results caused by ± 10% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 10% relative to nominal value:
+Ba    105    44.90   3946    4460   74098    518    100.0    6.164  !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba    105    44.90   3812    4163   51998    582    100.0    6.598

I'll tell you one thing, you can really "reach out and touch something!"

Or, if you want to stick with a 24 inch barrel:

Cartridge          : 6.5 Creedmoor Hornady
Bullet             : .264, 129, Nosler AccuBond LR 58943 G7
Useable Case Capaci: 47.572 grain H2O = 3.089 cm³
Cartridge O.A.L. L6: 2.800 inch = 71.12 mm
Barrel Length      : 24.0 inch = 609.6 mm
Powder             : Hodgdon H4350

Predicted data by increasing and decreasing the given charge,
incremented in steps of 2.0% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !

Step    Fill. Charge   Vel.  Energy   Pmax   Pmuz  Prop.Burnt B_Time
 %       %    Grains   fps   ft.lbs    psi    psi      %        ms

-20.0   84    35.92   2358    1592   33248   7795     90.7    1.518
-18.0   86    36.82   2414    1669   35462   8030     91.8    1.480
-16.0   88    37.72   2470    1747   37822   8259     92.9    1.441
-14.0   90    38.61   2526    1828   40336   8479     93.9    1.398
-12.0   92    39.51   2582    1910   42998   8691     94.8    1.357
-10.0   94    40.41   2638    1994   45813   8893     95.7    1.318
-08.0   96    41.31   2694    2080   48811   9085     96.5    1.280
-06.0   98    42.21   2750    2167   52007   9266     97.2    1.243
-04.0  100    43.10   2806    2255   55417   9434     97.8    1.208  ! Near Maximum !
-02.0  103    44.00   2862    2346   59057   9590     98.4    1.174  ! Near Maximum !
+00.0  105    44.90   2917    2437   62946   9733     98.8    1.142  ! Near Maximum !
+02.0  107    45.80   2972    2530   67104   9861     99.2    1.110  !DANGEROUS LOAD-DO NOT USE!
+04.0  109    46.70   3027    2625   71556   9975     99.5    1.080  !DANGEROUS LOAD-DO NOT USE!
+06.0  111    47.59   3082    2720   76326  10073     99.8    1.050  !DANGEROUS LOAD-DO NOT USE!
+08.0  113    48.49   3136    2817   81445  10155     99.9    1.022  !DANGEROUS LOAD-DO NOT USE!
+10.0  115    49.39   3190    2915   86946  10220    100.0    0.994  !DANGEROUS LOAD-DO NOT USE!

Results caused by ± 10% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 10% relative to nominal value:
+Ba    105    44.90   3034    2636   74098   9469    100.0    1.067  !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba    105    44.90   2757    2177   51998   9549     93.8    1.240

 

[Wyo7200]

Imagine the sag that barrel would have...

 

[adccoyote428]

Thanks for that info Dr Mike appreciate it greatly! Yes a 20 ft barrel would be a bugger to carry around or hunt with LOL.

 

[wildgene]

...well, a 21' barrel might be a little hard to maneuver, but it might be worth it for 3900fps... :shock: :roll: :lol: :mrgreen: