Which powder for more velocity?

[unstableryan]

Quickload isn't perfect but 44.8gr shows 60436 psi and 2849 fps.
a 105% load of h4350 (48gr) shows 54983 psi and 2780 fps.
Those are with a berger hunting vld at 2.800"

Here's a few powders that are at 60k psi and near 100% loading density.

Powder type Filling/Loading Ratio Charge Charge Vel. Prop.Burnt P max P muzz B_Time
% Grains Gramm fps % psi psi ms
--------------------------------- -----------------------------------------------------------------
Elcho 17 100.0 49.1 3.18 2930 99.9 56428 10662 1.080 ! Near Maximum !
Alliant Reloder-17 100.0 49.1 3.18 2930 99.9 56428 10662 1.080 ! Near Maximum !
ReloadSwiss RS 60 100.0 49.1 3.18 2923 100.0 54767 10703 1.090 ! Near Maximum !
Winchester 760 100.0 49.5 3.21 2905 97.0 58630 10656 1.075 ! Near Maximum !
Hodgdon H414 100.0 49.5 3.21 2905 97.0 58630 10656 1.075 ! Near Maximum !
Norma 203 old 98.3 46.5 3.01 2879 100.0 60000 9772 1.089 !DANGEROUS LOAD-DO NOT USE!
Bofors RP3 98.3 46.5 3.01 2879 100.0 60000 9772 1.089 !DANGEROUS LOAD-DO NOT USE!
Hodgdon H380 97.6 46.6 3.02 2870 98.9 60000 10009 1.082 !DANGEROUS LOAD-DO NOT USE!

I've been loading for a 7-08AI with a 22" barrel for with 139 and 140 gr bullets.

With Varget I've been achieving good results in accuracy at 44.8 gr of Varget at 2950 fps. I was starting to see some pressure signs around 3000 fps.

I've also tried H4350, but velocities were hovering around 2800 fps with fairly compressed loads.

Can anyone provide suggestions for alternative powders to try that may produce better velocities than the Varget, while maintaining safe pressures, but also being fairly temperature stable? This is a hunting rifle and will be used from +10 to -30 C.

 

[coleman1495]

I’ve had good results with D4895 from CanAm. 43.1gr under 139gr sst gives 2820fps from a 22”.

Varget is better but D4895 is half the price.

 

[cbh560]

Quickload isn't perfect but 44.8gr shows 60436 psi and 2849 fps.
a 105% load of h4350 (48gr) shows 54983 psi and 2780 fps.
Those are with a berger hunting vld at 2.800"

Here's a few powders that are at 60k psi and near 100% loading density.

Powder type Filling/Loading Ratio Charge Charge Vel. Prop.Burnt P max P muzz B_Time
% Grains Gramm fps % psi psi ms
--------------------------------- -----------------------------------------------------------------
Elcho 17 100.0 49.1 3.18 2930 99.9 56428 10662 1.080 ! Near Maximum !
Alliant Reloder-17 100.0 49.1 3.18 2930 99.9 56428 10662 1.080 ! Near Maximum !
ReloadSwiss RS 60 100.0 49.1 3.18 2923 100.0 54767 10703 1.090 ! Near Maximum !
Winchester 760 100.0 49.5 3.21 2905 97.0 58630 10656 1.075 ! Near Maximum !
Hodgdon H414 100.0 49.5 3.21 2905 97.0 58630 10656 1.075 ! Near Maximum !
Norma 203 old 98.3 46.5 3.01 2879 100.0 60000 9772 1.089 !DANGEROUS LOAD-DO NOT USE!
Bofors RP3 98.3 46.5 3.01 2879 100.0 60000 9772 1.089 !DANGEROUS LOAD-DO NOT USE!
Hodgdon H380 97.6 46.6 3.02 2870 98.9 60000 10009 1.082 !DANGEROUS LOAD-DO NOT USE!

These numbers are based off the standard 7-08 Rem cartridge in QL? Is there an option for inputs for the 7-08 improved? I'd be curious to see the numbers for the improved. I know I'm on the upper end of safe pressures with 44.8 gr of Varget, but I'm wondering how much the pressure would be reduced with the additional case volume of the improved cartridge.

 

[BCBRAD]

These numbers are based off the standard 7-08 Rem cartridge in QL? Is there an option for inputs for the 7-08 improved? I'd be curious to see the numbers for the improved. I know I'm on the upper end of safe pressures with 44.8 gr of Varget, but I'm wondering how much the pressure would be reduced with the additional case volume of the improved cartridge.

~3 grains of water between the two. Not much really.

 

[Buckmastr]

A plain jane 7-08 LVSF shoots 140 Sierra PH with Reloader 17 to nearly 3000 fps out of a 22" barrel. Quickload figures at 62k which I can live with especially since it groups great. A small bearing surface bullet plus RL 17 will get you the maximum speed.

 

[209jones]

2950 is about all you are likely to get safely, and that is questionable, out of a 7-08, AI or no. Appears you have a nice, fast barrel, nothing to complain about there. AI is no magic pixie dust, many cartridges don't see next to squat for improvement if proper pressure is run in them. You are getting about 100fps, so, you are doing well with the AI. I have one standard 7-08 that will comfortably do 2850 with a 140, one that I am wondering if it will crack 2800, I have about 1.5 gr yet to hit max book load, only just cracking 2700. Magnum primer may make a difference yet also. The fast one runs 1gr under max with a magnum primer and ball powder. Only used std primers so far in the other one. New gun's chamber is also .002 shorter. You'll find out how hot or not your existing load is after firing that brass 4-5 times, pockets will let you know for sure.

 

[huntingfamily]

These numbers are based off the standard 7-08 Rem cartridge in QL? Is there an option for inputs for the 7-08 improved? I'd be curious to see the numbers for the improved. I know I'm on the upper end of safe pressures with 44.8 gr of Varget, but I'm wondering how much the pressure would be reduced with the additional case volume of the improved cartridge.

The default QL #'s for 7mm-08 AI with a 22" barrel and the 140 nosler accubond bullet predict great results with either W760 or H414. Both are spherical powders and are temperature sensitive!

MAX pressure of 62,000 psi so start low and work up!

49.8 grains
~ 2945 fps

 

[huntingfamily]

These numbers are based off the standard 7-08 Rem cartridge in QL? Is there an option for inputs for the 7-08 improved? I'd be curious to see the numbers for the improved. I know I'm on the upper end of safe pressures with 44.8 gr of Varget, but I'm wondering how much the pressure would be reduced with the additional case volume of the improved cartridge.

QL also predicts that for Varget to produce a velocity of 2950 fps, the pressure would be ~ 68,700 psi in the AI. Just an fyi...

 

[chappy]

i prefer rel 19 in the 7 08,708ai and 280. seems to be the fastest loads for me.

 

[hunters home]

Never loaded for a 7/08AI, but in my standard 7mm/08 H 414/WW760 always worked great for velocity and accuracy. Winchester has a new ball powder, StaBall 6.5, which may be great in both 7mm/08. Higginson told me they should have some later in November. I think I'll get some and give it a try. Hogdon has some data on their site for this powder. Their velocity #'s are good.

 

[unstableryan]

These numbers are based off the standard 7-08 Rem cartridge in QL? Is there an option for inputs for the 7-08 improved? I'd be curious to see the numbers for the improved. I know I'm on the upper end of safe pressures with 44.8 gr of Varget, but I'm wondering how much the pressure would be reduced with the additional case volume of the improved cartridge.

No... ai version.

 

[hunters home]

These numbers are based off the standard 7-08 Rem cartridge in QL? Is there an option for inputs for the 7-08 improved? I'd be curious to see the numbers for the improved. I know I'm on the upper end of safe pressures with 44.8 gr of Varget, but I'm wondering how much the pressure would be reduced with the additional case volume of the improved cartridge.

My Quickload program for the 7mm/08 AI and the 140 gr Sierra and a default case cap of 58.3 grs and an OAL of 2.800, 44.8 grs of Varget gets 56002psi. Vel from a 24" barrel is appx 2856 ft/sec.

 

[john-brennan]

Sell it and buy a 7mm Rem mag if you need more speed.
You are not going to get much more then you are hitting now with a new powder, and 50fps difference means very little for hunting rounds.

X2 I agree I shoot a 7-08 my max velocity is 2900fps with H4350 and R19

 

[todbartell]

Cartridge          : 7 mm-08 Ack. Imp. Rem.
Bullet             : .284, 140, Nosler AccuBond 59992
Useable Case Capaci: 50.791 grain H2O = 3.298 cm³
Cartridge O.A.L. L6: 2.800 inch = 71.12 mm
Barrel Length      : 22.0 inch = 558.8 mm

Predicted Data for Indicated Charges of the Following Powders.
Matching Maximum Pressure: 64000 psi, or 441 MPa
or a maximum loading ratio or filling of 110 %
These calculations refer to your specified settings in QuickLOAD 'Cartridge Dimensions' window.
C A U T I O N : any load listed can result in a powder charge that falls below minimum suggested
loads or exceeds maximum suggested loads as presented in current handloading manuals. Understand
that all of the listed powders can be unsuitable for the given combination of cartridge, bullet
and gun. Actual load order can vary, depending upon lot-to-lot powder and component variations.
USE ONLY FOR COMPARISON !

93 loads produced a Loading Ratio below user-defined minimum of 80%. These powders have been skipped.
Powder type          Filling/Loading Ratio  Charge    Charge   Vel. Prop.Burnt P max  P muzz  B_Time
                                      %     Grains    Gramm   fps     %       psi     psi    ms
---------------------------------  -----------------------------------------------------------------
Alliant Reloder-26                 109.3     55.0     3.56    3042    99.4    64000   11595   1.018  ! Near Maximum !
Alliant Reloder-17                  98.9     48.6     3.15    2977   100.0    64000   10351   1.013  ! Near Maximum !
Alliant Reloder-16                 105.7     48.2     3.12    2946    99.9    64000   10216   1.023  ! Near Maximum !
IMR 7828 SSC                       109.7     52.7     3.42    2938    93.6    64000   10939   1.027  ! Near Maximum !
Ramshot Hunter                     103.6     50.1     3.25    2922    98.3    64000   10453   1.025  ! Near Maximum !
Vihtavuori N560                    110.0     52.6     3.41    2918    92.7    61028   11177   1.050  ! Near Maximum !
Alliant Reloder-19                 108.2     50.7     3.28    2910    95.7    64000   10556   1.022  ! Near Maximum !
Hodgdon H414                        97.7     48.4     3.13    2907    97.5    64000   10398   1.031  ! Near Maximum !
Winchester 760                      97.7     48.4     3.13    2907    97.5    64000   10398   1.031  ! Near Maximum !
Alliant Reloder-22                 110.0     52.1     3.37    2901    95.0    60411   10916   1.037  ! Near Maximum !
Accurate MAGPRO                    110.0     54.8     3.55    2889    90.4    60385   11061   1.055  ! Near Maximum !
Hodgdon CFE223                      87.9     45.8     2.97    2885   100.0    64000    9648   1.037  ! Near Maximum !
Ramshot Magnum                     110.0     56.1     3.63    2885    95.5    62189   10481   1.038  ! Near Maximum !
IMR 4831                           107.9     48.4     3.13    2884    99.5    64000    9896   1.040  ! Near Maximum !
Ramshot Big Game                    93.1     46.4     3.01    2884    99.9    64000    9675   1.036  ! Near Maximum !
Hodgdon Hybrid 100V                105.9     48.0     3.11    2880   100.0    64000    9363   1.030  ! Near Maximum !
IMR 4895                            92.8     43.5     2.82    2878    99.9    64000    9701   1.045  ! Near Maximum !
Alliant Reloder-15                  93.7     43.9     2.84    2868    99.8    64000    9665   1.046  ! Near Maximum !
Hodgdon H4831 SC                   109.1     51.6     3.34    2864    92.8    64000   10174   1.024  ! Near Maximum !
Hodgdon BL-C2                       88.4     45.2     2.93    2864   100.0    64000    9435   1.047  ! Near Maximum !
Winchester 748                      86.0     43.3     2.81    2861   100.0    64000    9093   1.043  ! Near Maximum !
Norma 203 old                       95.1     45.0     2.92    2856   100.0    64000    9411   1.053  ! Near Maximum !
Hodgdon H4895                       90.5     42.4     2.75    2855   100.0    64000    9385   1.049  ! Near Maximum !
Hodgdon H4350                      105.1     48.2     3.12    2842    96.7    64000    9769   1.038  ! Near Maximum !
Hodgdon VARGET                      96.6     43.8     2.84    2835    99.7    64000    9324   1.044  ! Near Maximum !

The 7mm-08 Ackley has 6% more case capacity than a standard 7mm-08 Rem. This will create 2% more velocity, apples to apples (approx 60 fps)

*Edit - I used 59.3 H2O as case capacity (measured averages from a few 7-08 Ackleys with different makes of brass), also don't forget to adjust the start pressure up from the default of 3626psi. I used 9956 psi for the above predictions, which would simulate .030" of bullet jump to lands

 

[Buckmastr]

Isn't Saami max on a 7mm-08 Rem 61000psi?

 

[huntingfamily]

Isn't Saami max on a 7mm-08 Rem 61000psi?

I'm not sure why todbartell went with 64,000 psi max. Also, 110% case fill capacity seems very compressed, no?

Todbartell, I'm envious of how you post QL results in that way.

 

[todbartell]

I tweaked the parameters, as it's obvious the 7-08 Ackley will not hit 3000 fps from a 22" barrel with 140gr without A) high PSI, B) highly compressed loads of slow burning powders

Myself I rarely go above 104% load density, I find the more compressed the load is, the harder it is to keep the OAL at a consistent length. They tend to creep out of the case over time too. this can lead to reliability issues in certain applications (loaded right close to end of magazine box before they creep)

Use the above list of loads for comparison only. A temp stable, high velocity powder choice for the 7-08 will be RL16, H4895 or Varget. I know a couple 7mm-08 owners and the claims of 3000 fps with 140's always seemed so magical. I know one guy bought one used and it came with a bunch of reloads, he ended up having to pull them all due to over pressure

 

[todbartell]

On a side note, in my testing I have found some temperature "sensitive" powders aren't too bad in typical hunting conditions (-15c to +15c), it's the really hot weather than can/will spike results.

Similar cartridge, the 6.5 Creedmoor

-15c
H4350 (stable) ~ 2635 fps
IMR 4451 (stable) ~ 2710 fps
IMR 4831 (sensitive) ~ 2449 fps
Win 760 (sensitive) ~ 2534 fps
RL16 (stable) ~ 2694 fps

+13c
H4350 (stable) ~ 2622 fps
IMR 4451 (stable) ~ 2657 fps
IMR 4831 (sensitive) ~ 2453 fps
Win 760 (sensitive) ~ 2555 fps
RL16 (stable) ~ 2675 fps

+29c
H4350 (stable) ~ 2646 fps
IMR 4451 (stable) ~ 2679 fps
IMR 4831 (sensitive) ~ 2526 fps
Win 760 (sensitive) ~ 2606 fps
RL16 (stable) ~ 2675 fps

 

[todbartell]

And 308 Winchester :

-15c
H4895 (stable) ~ 2502 fps
IMR 4166 (stable) ~ 2570 fps
IMR 4064 (sensitive) ~ 2435 fps
Alliant AR Comp (stable) ~ 2358 fps
Win 748 (sensitive) ~ 2419 fps

+13c
H4895 (stable) ~ 2440 fps
IMR 4166 (stable) ~ 2511 fps
IMR 4064 (sensitive) ~ 2438 fps
Alliant AR Comp (stable) ~ 2360 fps
Win 748 (sensitive) ~ 2432 fps

+29c
H4895 (stable) ~ 2477 fps
IMR 4166 (stable) ~ 2526 fps
IMR 4064 (sensitive) ~ 2497 fps
Alliant AR Comp (stable) ~ 2347 fps
Win 748 (sensitive) ~ 2482 fps

 

[cbh560]

Cartridge          : 7 mm-08 Ack. Imp. Rem.
Bullet             : .284, 140, Nosler AccuBond 59992
Useable Case Capaci: 50.791 grain H2O = 3.298 cm³
Cartridge O.A.L. L6: 2.800 inch = 71.12 mm
Barrel Length      : 22.0 inch = 558.8 mm

Predicted Data for Indicated Charges of the Following Powders.
Matching Maximum Pressure: 64000 psi, or 441 MPa
or a maximum loading ratio or filling of 110 %
These calculations refer to your specified settings in QuickLOAD 'Cartridge Dimensions' window.
C A U T I O N : any load listed can result in a powder charge that falls below minimum suggested
loads or exceeds maximum suggested loads as presented in current handloading manuals. Understand
that all of the listed powders can be unsuitable for the given combination of cartridge, bullet
and gun. Actual load order can vary, depending upon lot-to-lot powder and component variations.
USE ONLY FOR COMPARISON !

93 loads produced a Loading Ratio below user-defined minimum of 80%. These powders have been skipped.
Powder type          Filling/Loading Ratio  Charge    Charge   Vel. Prop.Burnt P max  P muzz  B_Time
                                      %     Grains    Gramm   fps     %       psi     psi    ms
---------------------------------  -----------------------------------------------------------------
Alliant Reloder-26                 109.3     55.0     3.56    3042    99.4    64000   11595   1.018  ! Near Maximum !
Alliant Reloder-17                  98.9     48.6     3.15    2977   100.0    64000   10351   1.013  ! Near Maximum !
Alliant Reloder-16                 105.7     48.2     3.12    2946    99.9    64000   10216   1.023  ! Near Maximum !
IMR 7828 SSC                       109.7     52.7     3.42    2938    93.6    64000   10939   1.027  ! Near Maximum !
Ramshot Hunter                     103.6     50.1     3.25    2922    98.3    64000   10453   1.025  ! Near Maximum !
Vihtavuori N560                    110.0     52.6     3.41    2918    92.7    61028   11177   1.050  ! Near Maximum !
Alliant Reloder-19                 108.2     50.7     3.28    2910    95.7    64000   10556   1.022  ! Near Maximum !
Hodgdon H414                        97.7     48.4     3.13    2907    97.5    64000   10398   1.031  ! Near Maximum !
Winchester 760                      97.7     48.4     3.13    2907    97.5    64000   10398   1.031  ! Near Maximum !
Alliant Reloder-22                 110.0     52.1     3.37    2901    95.0    60411   10916   1.037  ! Near Maximum !
Accurate MAGPRO                    110.0     54.8     3.55    2889    90.4    60385   11061   1.055  ! Near Maximum !
Hodgdon CFE223                      87.9     45.8     2.97    2885   100.0    64000    9648   1.037  ! Near Maximum !
Ramshot Magnum                     110.0     56.1     3.63    2885    95.5    62189   10481   1.038  ! Near Maximum !
IMR 4831                           107.9     48.4     3.13    2884    99.5    64000    9896   1.040  ! Near Maximum !
Ramshot Big Game                    93.1     46.4     3.01    2884    99.9    64000    9675   1.036  ! Near Maximum !
Hodgdon Hybrid 100V                105.9     48.0     3.11    2880   100.0    64000    9363   1.030  ! Near Maximum !
IMR 4895                            92.8     43.5     2.82    2878    99.9    64000    9701   1.045  ! Near Maximum !
Alliant Reloder-15                  93.7     43.9     2.84    2868    99.8    64000    9665   1.046  ! Near Maximum !
Hodgdon H4831 SC                   109.1     51.6     3.34    2864    92.8    64000   10174   1.024  ! Near Maximum !
Hodgdon BL-C2                       88.4     45.2     2.93    2864   100.0    64000    9435   1.047  ! Near Maximum !
Winchester 748                      86.0     43.3     2.81    2861   100.0    64000    9093   1.043  ! Near Maximum !
Norma 203 old                       95.1     45.0     2.92    2856   100.0    64000    9411   1.053  ! Near Maximum !
Hodgdon H4895                       90.5     42.4     2.75    2855   100.0    64000    9385   1.049  ! Near Maximum !
Hodgdon H4350                      105.1     48.2     3.12    2842    96.7    64000    9769   1.038  ! Near Maximum !
Hodgdon VARGET                      96.6     43.8     2.84    2835    99.7    64000    9324   1.044  ! Near Maximum !

The 7mm-08 Ackley has 6% more case capacity than a standard 7mm-08 Rem. This will create 2% more velocity, apples to apples (approx 60 fps)

*Edit - I used 59.3 H2O as case capacity (measured averages from a few 7-08 Ackleys with different makes of brass), also don't forget to adjust the start pressure up from the default of 3626psi. I used 9956 psi for the above predictions, which would simulate .030" of bullet jump to lands

I'm not entirely sure how the "start pressure" works. Would I be along the correct line of thinking to say that as the bullet makes the jump to the lands that the pressure build up to to get it to this point is the start pressure in your example that would be 0.030" of travel). Would a larger jump increase start pressure and therefore total pressure? From what I recall of pressure curves they're quite sharp initially and then reduce as the powder burns and the bullets travels the length of the barrel.