Why use roundnose bullets in rifle cartridges?

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Why use roundnose bullets in rifle cartridges?

Post by shazz » 16 Jan 2018, 3:16 pm

Hi guys,

What's the reason to choose a round nose bullet instead of the normal pointed options?

Thanks.

(edit: Talking about shooting rifles here, not pistols)
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Re: Why use roundnose bullets in rifle cartridges?

Post by AusTac » 16 Jan 2018, 3:29 pm

Cut through brush way better than spitzers and for lever actions they won't detonate in the tube like nose of bullet smash into primer of another sort of thing, some manufactures make special lever rounds with plastic tips now for that reason
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Re: Why use roundnose bullets in rifle cartridges?

Post by Supaduke » 16 Jan 2018, 4:21 pm

Round nose arguably cause a more traumatic wound channel.
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Re: Why use roundnose bullets in rifle cartridges?

Post by Daddybang » 16 Jan 2018, 4:51 pm

Cause they punch hard!! :drinks:
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Re: Why use roundnose bullets in rifle cartridges?

Post by Oldbloke » 16 Jan 2018, 5:40 pm

Supaduke wrote:Round nose arguably cause a more traumatic wound channel.


What about hollow points?
What about the point hardness?
What about what you hit, bone or soft tissue?
What about impact speed?

There are a lot of variables.

And I'm inclined to think the "brush bucking" argument is an old wives tale. But may well be proven wrong.

This could get interesting.
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Re: Why use roundnose bullets in rifle cartridges?

Post by bladeracer » 16 Jan 2018, 5:53 pm

shazz wrote:Hi guys,

What's the reason to choose a round nose bullet instead of the normal pointed options?

Thanks.

(edit: Talking about shooting rifles here, not pistols)


They might feed better than pointed bullets, you can run a heavy but stubby bullet that will stabilise in fairly relaxed rifling, you get more bearing surface in contact with the rifling, they're often cheaper than pointed bullets, they hit harder - basically, there a lots of reasons for both choices.
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Re: Why use roundnose bullets in rifle cartridges?

Post by Supaduke » 16 Jan 2018, 7:29 pm

Oldbloke wrote:
Supaduke wrote:Round nose arguably cause a more traumatic wound channel.


What about hollow points?
What about the point hardness?
What about what you hit, bone or soft tissue?
What about impact speed?

There are a lot of variables.

And I'm inclined to think the "brush bucking" argument is an old wives tale. But may well be proven wrong.

This could get interesting.


It was a Spitzer vs round nose comparison.

Round nose don't pierce as well as a pointy Spitzer and theoretically will deform quicker and tear a more ragged hole.
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Re: Why use roundnose bullets in rifle cartridges?

Post by Archie » 16 Jan 2018, 8:07 pm

I suppose that for a given length of bullet the round nose would have greater sectional density than a spitzer.

Although unless you're shooting an elephant in the head I don't know whether that actually matters that much.
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Re: Why use roundnose bullets in rifle cartridges?

Post by Gamerancher » 17 Jan 2018, 7:55 am

Sectional density has nothing to do with the shape of the bullet. It is calculated by the weight of the bullet ( in pounds ) divided by the diameter ( in inches ) squared.
Bullets of the same weight in the same calibre have the same S.D no matter what the shape.
For example, a 150gr spitzer in .308 has the same S.D as a 150gr roundnose in .308. That is, they both have a S.D of .226
The heavier a bullet is for calibre, the higher the S.D.
Ballistic co-efficient is dependent on bullet shape. Perhaps you are confusing the two? :unknown:
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Re: Why use roundnose bullets in rifle cartridges?

Post by Archie » 17 Jan 2018, 10:14 am

Gamerancher wrote:Sectional density has nothing to do with the shape of the bullet. It is calculated by the weight of the bullet ( in pounds ) divided by the diameter ( in inches ) squared.
Bullets of the same weight in the same calibre have the same S.D no matter what the shape.
For example, a 150gr spitzer in .308 has the same S.D as a 150gr roundnose in .308. That is, they both have a S.D of .226
The heavier a bullet is for calibre, the higher the S.D.
Ballistic co-efficient is dependent on bullet shape. Perhaps you are confusing the two? :unknown:


I could be wrong but don't think I am? T

he key qualifier was "for a given bullet length". For the same diameter, a round nose bullet should have a higher mass than a spitzer of the same length (although I could see how it would in practice vary dependent on the specific materials used in construction of each). To use your example, my assumption is that, if a .308 spitzer weighed in at 150gr (and ignoring the possibility of different materials used in each), a .308 roundnose of the same length as the spitzer would probably be greater than 150gr. Is that correct?
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Re: Why use roundnose bullets in rifle cartridges?

Post by SendIt » 17 Jan 2018, 11:24 am

You could say they're a slightly harder hitting, shorter range round.

They cut through brush better as they have a more solid shaped tip.

Weight retention is typically a little better, again because of the shape of the tip it holds together better compared to a spitzer where tip may shatter and all the weight retention is done by the body of the bullet.

Less initial penetration and more immediate expansion means a bigger wound channel sooner.

Hunting tough game at modest ranges is where they excel. Think hunting big boar in a forest, or hunting scrub bulls.
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Re: Why use roundnose bullets in rifle cartridges?

Post by Gamerancher » 17 Jan 2018, 11:58 am

Wasn't having a go at you Archie,
Yes, I will concede that a one inch long round nose bullet is going to be heavier than a one inch long spitzer, boat tail bullet.
I don't select my bullets on length, I select based on weight and construction / design and intended purpose..
My point being that sectional density has nothing to do with the shape or construction of a bullet. It is purely mathematical.
S.D = ( weight / diameter ) squared.
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Re: Why use roundnose bullets in rifle cartridges?

Post by Archie » 17 Jan 2018, 7:49 pm

All good mate.
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Re: Why use roundnose bullets in rifle cartridges?

Post by Lumbajak » 17 Jan 2018, 7:59 pm

Because out of the 2 loading sp’s backwards is

A - cheaper
B - easier
C - leaves more room for powder at seating depth
D - I try to use less pointy bullets so as to not upset my leftard vegan hipster neighbours
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Re: Why use roundnose bullets in rifle cartridges?

Post by Noisydad » 17 Jan 2018, 9:49 pm

Weight distribution is another reason - directly related to BC.
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Re: Why use roundnose bullets in rifle cartridges?

Post by slickncghia » 18 Jan 2018, 11:43 am

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 deanp100 » 20 Jan 2018, 7:17 pm

For one reason only. When they hit things they make a sound like a cricket bat on a junkie.
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Re: Why use roundnose bullets in rifle cartridges?

Post by in2anity » 23 Jan 2018, 2:22 pm

deanp100 wrote:For one reason only. When they hit things they make a sound like a cricket bat on a junkie.


ha, they do! BANG ... THUNK!
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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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