Real BC of the152 Hammer Hunter 308 bullet?

[SuperBruce]

I've had good luck with the 151 absolute hammers and the advertised BC has been true for me. Never being satisfied, I want to try out the 152 hammer hunters since they have a significantly higher advertised BC (HH has a G7 of .208 vs .185 for the AH) and it looks like people are still getting them moving pretty fast out of a 308 win. However, the HH BC is "estimated" vs "calculated from shot drops" so I was wondering if anybody has verified the HH BC one way or the other.

Thanks in advance.

 

[Zen Archery]

All B.C. is estimate and not finite number. If you have a chrono. and a long range place to shoot you can figure it out for that days environmental condition and elevation. I'd start with what we publish then make corrections.

My experience unless you are launching a projectile into its upper edge approaching subsonic ranges, too much is made up of BC.

Use what BC Hammer is suggesting and adjust corrections when you see a variance.

 

[ButterBean]

All B.C. is estimate and not finite number. If you have a chrono. and a long range place to shoot you can figure it out for that days environmental condition and elevation. I'd start with what we publish then make corrections.

My experience unless you are launching a projectile into its upper edge approaching subsonic ranges, too much is made up of BC.

Use what BC Hammer is suggesting and adjust corrections when you see a variance.

X-2

 

[SuperBruce]

All B.C. is estimate and not finite number. If you have a chrono. and a long range place to shoot you can figure it out for that days environmental condition and elevation. I'd start with what we publish then make corrections.

My experience unless you are launching a projectile into its upper edge approaching subsonic ranges, too much is made up of BC.

Use what BC Hammer is suggesting and adjust corrections when you see a variance.

I totally get (and respect) that lots of folks don't care about the specifics because in their situation it doesn't matter but this question is very much about specifics. I'm trying to stretch this short barreled 308 Win (18", super handy rifle) out to 600 yards effective range and if the BC is correct (or an underestimate) then it maks a material difference that far out.

I'm fully aware BC is a parameter to a model which is a simplification of the true ballistics. However, these models are really good so long as your parameters are accurate and I want to know if the advertised BC is accurate to determine whether it's worth investing the $ and time working up a load vs the 151 AH's that I have already worked up.

 

[Zen Archery]

Now you got me doing maths!!!
Depending on your altitude and components you should easily be able to get the 152gr into the 2640-2650fps (if not faster/hotter).

Transonic range is in the mid 800 range (depending on altitude and environmental). At 600 yards I'd be surprised if the G7 .208 will need more than +\- .005 adjustment at that distance.

Send it and let us know. I'm currently playing with the .308, 174gr at 2544 fps. Out to 440 yards (current max distance) no BC correction.

Keep us posted.

 

[SuperBruce]

Now you got me doing maths!!!
Depending on your altitude and components you should easily be able to get the 152gr into the 2640-2650fps (if not faster/hotter).

Transonic range is in the mid 800 range (depending on altitude and environmental). At 600 yards I'd be surprised if the G7 .208 will need more than +\- .005 adjustment at that distance.

Send it and let us know. I'm currently playing with the .308, 174gr at 2544 fps. Out to 440 yards (current max distance) no BC correction.

Keep us posted.

Thanks for the info, +/-1 0.005 seems workable. The adjustment isn't the big thing I'm worried about (as you note it's just a click or two away) but the energy and impact velocity. The extra BC may make the difference between an effective/ethical elk rifle at 500 yards vs 600 yards. My hunting range starts at 5500 ft and is more typically 7000+ ft so that certainly helps stretch things out.

I'm able to get the 151 AH to 3020 fps with TAC before hitting any signs of pressure but the accuracy and velocity consistency isn't there at top speeds so I backed down to 2930 fps. There is at least one report of getting the 152 running to 3040 fps using TAC out of a 22" barrel with good accuracy so there is a reasonable chance I find a good load that is the same speed or only a touch slower with 152 hunters.

Odds are I'll buy some and if I do I'll make sure to report back.
Ordered.

 

[SuperBruce]

First bit of data is in! I loaded up the 152 Hammer Hunters over TAC in Lapua brass and worked up to what Ramshot has as a general concensus for the max on 150gr bullets. In my 18" Bergara Ridge I was able to get them up to 2900 fps and no pressure signs yet so I don't know how much headroom I still have. Groups (admittedly of only 2, needs confirming) and SD was really good at ~2870 fps over a 0.6gr window so chances are that is where the load will end up.

So, if the BC values advertised are correct, the Hammer Hunters greater BC will make up for the lower velocity between 100 and 200 yards. If the better groups hold up it will certainly be a win just from that: my 151 AH loads have opened up a bit with the changing weather but with the HH's the accuracy node looks to be a touch wider and the point of impact a bit more consistent between velocities.