Why use roundnose bullets in rifle cartridges?

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Re: Why use roundnose bullets in rifle cartridges?

Post by southeast varmiter » 25 Jan 2018, 6:50 am

Your almost right. The reason they are made for non dangerous game calibers is bullet stabilization.
It’s all about bullet length and rate of twist.
To have a heavier bullet it either needs to be longer or different ogive. The longer the bullet the greater the rate of twist needed to stabilize. Round nose bullets get around this by being heavier but not getting longer.

slickncghia wrote:deflection maybe probably.
RN Soft points can open up quicker at lower velocities depending on design with more frontal lead exposed.

For me the main reason as was mentioned earlier. Round nose means more weight for a given length which means more case capacity for powder when you start to get up to the really high bullet weights and then more velocity

only worth it for large game at short distances.

ie example with guess velocities.
Hornady 220gn .308 Round nose length = 1.283 in
Hornady 220gn .308 eld-x length = 1.63 in

Running both bullets out of a 30-06 you might get (guess) 150-300 ft/sec more out of the Round nose.

that is an extreme example and the velocity would quickly drop for longer range shots with the RN but for a charging buff at 25m the RN would be the better choice.
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Re: Why use roundnose bullets in rifle cartridges?

Post by Bills Shed » 25 Jan 2018, 6:52 am

I build the round nose in the 40 gn for the 22 hornet. Those long pointy "modern" projectiles have to be seated into the case a long way in order to use the magazine. A round nose 40gn of the hornet is no big game cartridge but makes a very decent job for my hunting requirements.

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Re: Why use roundnose bullets in rifle cartridges?

Post by Oldbloke » 25 Jan 2018, 8:10 am

All about compromise, pointy means flatter trajectory.
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Re: Why use roundnose bullets in rifle cartridges?

Post by BBJ » 25 Jan 2018, 12:12 pm

Oldbloke wrote:All about compromise, pointy means flatter trajectory.


More energy retained at extended ranges too (not that it will matter for most).
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Re: Why use roundnose bullets in rifle cartridges?

Post by Oldbloke » 26 Jan 2018, 6:24 am

BBJ wrote:
More energy retained at extended ranges too (not that it will matter for most).


For an indication just look at the trajectory of a 30-30. It's like a rainbow beyond about 150 yards. Hence bolt actions are very popular.
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