Nosler long range accbond and my experience.

[Michael Eichele]

I'm not a 308 shooter but I would guess the higher BC of the 210 would give it better performance than the 190. Also, my philosophy, especially when it comes to frangible bullets, is that Greater Mass + Lower Velocity = Better Terminal Performance.

I can't argue with that but I think this is a case of where paper ballistics look better than reality. While I am a fan of 210 class bullets in the 308, I have had better success (all things considered) with the 190 class bullets than the 210 class ran in my 308s. Maybe part of my mentality on this is because my 300 shoots the 210s so well. If I need a 210, I'll be using the 300 over the 308. One of my favorite things about the 308 is mild recoil. The 190s still offer great ballistic performance with mild recoil. I find the 210s kick me much harder especially when driven to velocities that makes using them worthwhile. If I'm going to take the abuse, I may as well make it count and make it worth my while. That is, just grab the 300.

 

[Michael Eichele]

Are you going to get a chance to this year or is the season already over for you?

Unfortunately, my season is done. Only bagged an antelope and that was with my 6.5x284/140VLD.

 

[Kennibear]

Most of the responses have been on 7mm or 30 cal. Has anybody shot the 6.5mm? There are decent cartridges in this caliber and would make a nice light rig.

On the reduced velocity. The forward velocity drops with range but the rotational velocity does not. This was pointed out by a shooting buddy back in 1973 (he designed missile guidance systems). The centrifugal force of the spin contributes a small amount to the expansion of the bullet. Not a lot but a bullet shot from a 308 and one from a 300 RUM when striking at the same velocity will not expand the same. It's not much but I'm told it's there.

WildRose, hope you heal well and soon.

 

[Michael Eichele]

Most of the responses have been on 7mm or 30 cal. Has anybody shot the 6.5mm? There are decent cartridges in this caliber and would make a nice light rig.

On the reduced velocity. The forward velocity drops with range but the rotational velocity does not. This was pointed out by a shooting buddy back in 1973 (he designed missile guidance systems). The centrifugal force of the spin contributes a small amount to the expansion of the bullet. Not a lot but a bullet shot from a 308 and one from a 300 RUM when striking at the same velocity will not expand the same. It's not much but I'm told it's there.

That largely depends on the twist rate...

 

[elkaholic]

Most of the responses have been on 7mm or 30 cal. Has anybody shot the 6.5mm? There are decent cartridges in this caliber and would make a nice light rig.

On the reduced velocity. The forward velocity drops with range but the rotational velocity does not. This was pointed out by a shooting buddy back in 1973 (he designed missile guidance systems). The centrifugal force of the spin contributes a small amount to the expansion of the bullet. Not a lot but a bullet shot from a 308 and one from a 300 RUM when striking at the same velocity will not expand the same. It's not much but I'm told it's there.

WildRose, hope you heal well and soon.

True! There were military tests run years ago that demonstrated this. They fired the same 110 grain bullet out of an M1 carbine and the M1 ('o6). The carbine was fired point blank with a 2000 ish mv, and the M1 at a range which would duplicate the carbine velocity. The carbine had a 16 twist and the M1 a 10. Bottom line, the only variable was the much higher rotational velocity of the '06. The resulting wound channels were "dramatic". The '06 blew a far wider diameter hole in the gel. I have had people dispute this in the past, but I for one am convinced.......Rich

 

[NONYA]

Nosler isnt what it once was,dont waste your money.

 

[WildRose]

Most of the responses have been on 7mm or 30 cal. Has anybody shot the 6.5mm? There are decent cartridges in this caliber and would make a nice light rig.

On the reduced velocity. The forward velocity drops with range but the rotational velocity does not. This was pointed out by a shooting buddy back in 1973 (he designed missile guidance systems). The centrifugal force of the spin contributes a small amount to the expansion of the bullet. Not a lot but a bullet shot from a 308 and one from a 300 RUM when striking at the same velocity will not expand the same. It's not much but I'm told it's there.

WildRose, hope you heal well and soon.

Thanks Kenni, I will, I always do. Just the cost of living a life at full throttle for about 30 years. The human body is like a car, if you jump in and mash the pedal to the floor and keep driving it that way for years, there is a price to be paid. I should be good for another hundred thousand miles or so though if I don't over do it and rush the rehab.

 

[WildRose]

That largely depends on the twist rate...

Yep, which is why the ideal twist rate for a given bullet varies with muzzle velocity. The faster they run down the barrel the slower the twist rate necessary to stabilize them and vice versa.

 

[Michael Eichele]

Thanks Kenni, I will, I always do. Just the cost of living a life at full throttle for about 30 years. The human body is like a car, if you jump in and mash the pedal to the floor and keep driving it that way for years, there is a price to be paid. I should be good for another hundred thousand miles or so though if I don't over do it and rush the rehab.

Glad to know I'm not alone in that regard. I'm 38 and ache from head to toe most days. My knees, back, shoulders and neck are almost always on fire. Too many quad, dirt bike and bike accidents, hardcore backcountry hunting etc...has really taken a toll. That said, a brand new car will eventually rot just sitting in the driveway never being driven. Takes longer but in the end, I'd rather be in the shape I'm in now then never experienced the joys of going all out on the things I enjoy. I'm on that last 1/4 tank with 125 miles yet to go. I've slowed down to 45-50 mph from 95 to save fuel. With a little throttle control and patience, I think I'll make it...

 

[MontanaRifleman]

Yep, which is why the ideal twist rate for a given bullet varies with muzzle velocity. The faster they run down the barrel the slower the twist rate necessary to stabilize them and vice versa.

This is true, but after playing with some twist calculators I found velocity has little effect on stabilization. Some, but not a lot. Elevation has a significant effect and temp has some effect as well.

 

[Pdvdh]

This is true, but after playing with some twist calculators I found velocity has little effect on stabilization. Some, but not a lot. Elevation has a significant effect and temp has some effect as well.

Agreed. I think the affect of varying MV is given too much significance in the role it plays in obtaining bullet stability. The research I've done led to your same conclusions.

Cutting Edge Bullets provides some insights on their web site about bullet twist rates and its affect on their bullets maintaining a straight path after impact with game animals. They believe their bullets are either more, or less, likely to maintain a straight flight path while penetrating game animals, depending on their bullets' twist rate. That's another topic... albeit an interesting one.

 

[WildRose]

Agreed. I think the affect of varying MV is given too much significance in the role it plays in obtaining bullet stability. The research I've done led to your same conclusions.

Cutting Edge Bullets provides some insights on their web site about bullet twist rates and its affect on their bullets maintaining a straight path after impact with game animals. They believe their bullets are either more, or less, likely to maintain a straight flight path while penetrating game animals, depending on their bullets' twist rate. That's another topic... albeit an interesting one.

I agree, it's just that how fast something is spinning is a function of both velocity and twist rate. Once the bullet is stabilized though, it remains so until minimal velocity is reaced for that bullet design. Once the bullet is spinning the rotational velocity doesn't change much throughout the flight because there is negligible resistance to same.

 

[Michael Eichele]

You all have illustrated exactly why we don't use RPM to calculate stability. It's much more complicated than that. As Mark pointed out, air density has a lot to do with it. Air density has many more times an effect than RPM alone. I have personally fired gs177 30 cal bullets at sea level in 20 degree air in an 11x barrel with dramatic keyholes at 100 yards where at 5000' and 60 degrees they shoot just fine. All those findings are spot on with the miller formula. I also played with the 208 Amax in a 12x barrel/308 velocities comparing with the miller formula and again found it spot on. Every where it said it should be at 1.0 or greater drilled perfect holes. When it predicted <1.0, the were keyholing. I was testing this in various temps with a combo that is marginal to gain an accurate picture as to how accurate the miller formula is. It seems as if it is dead on. These examples are an area where higher velocity can help but it's the difference between a .95 stability factor to a 1.0 factor. It'll never take it from .8 to 1.5. IMHO, 1.5 is the best balance where you maximize your BC and ensure stability over a broad range of conditions. Too little and it can take longer for the yaw to settle down, too much and the nose doesn't want to follow the line of trajectory. Both negatively affect BC to some degree or another. Maybe not a ton, but every little bit adds up.

 

[WildRose]

You all have illustrated exactly why we don't use RPM to calculate stability. It's much more complicated than that. As Mark pointed out, air density has a lot to do with it. Air density has many more times an effect than RPM alone. I have personally fired gs177 30 cal bullets at sea level in 20 degree air in an 11x barrel with dramatic keyholes at 100 yards where at 5000' and 60 degrees they shoot just fine. All those findings are spot on with the miller formula. I also played with the 208 Amax in a 12x barrel/308 velocities comparing with the miller formula and again found it spot on. Every where it said it should be at 1.0 or greater drilled perfect holes. When it predicted <1.0, the were keyholing. I was testing this in various temps with a combo that is marginal to gain an accurate picture as to how accurate the miller formula is. It seems as if it is dead on. These examples are an area where higher velocity can help but it's the difference between a .95 stability factor to a 1.0 factor. It'll never take it from .8 to 1.5. IMHO, 1.5 is the best balance where you maximize your BC and ensure stability over a broad range of conditions. Too little and it can take longer for the yaw to settle down, too much and the nose doesn't want to follow the line of trajectory. Both negatively affect BC to some degree or another. Maybe not a ton, but every little bit adds up.

Michael let me add for those who don't understand. The keyholing effect described above is when the bullet impacts the target sideways similar to a deflected or tumbling bullet can.