Bullet type matters?

[DynoDan1]

A question I have is in regards to types of bullets.
I have read and heard that there are basically 3 types of bullets.
Secant, tangent, and hybrid ogives.
Which is better/ preferred? Why?
I've heard of trimming the outside of the case neck, not sure why people do it though.

 

[n2omike]

Better for what? All have their applications.

For hunting small game, jacketed hollow points are great. No need to overthink those. For medium/big game, about any jacketed soft point is good up to around 2800 fps. For tough game and high/magnum velocities, bonded bullets are needed to keep the bullet from disintegrating.

 

[Riomouse911]

You’re listing shape profiles for pointed (Spitzer) type bullets (secant, tangent and hybrid ogive) . There are more shapes than that.

https://www.nrafamily.org/articles/2020/8/24/what-is-an-ogive-profile



For example: Solid bullets for dangerous game rifles may not have much, if any ogive, like these hydrostatically stabilized Woodleigh bullets.



Lever gun Round Nose bullets and 160 gr + RN for 6.5x55 loads are often long with neatly straight sides.



Stay safe.

 

[DynoDan1]

Better for what? All have their applications.

For hunting small game, jacketed hollow points are great. No need to overthink those. For medium/big game, about any jacketed soft point is good up to around 2800 fps. For tough game and high/magnum velocities, bonded bullets are needed to keep the bullet from disintegrating.

Okay, for clarification, I am just a target shooter.
100 yards-1000 yards ( I have yet to try 1000 yards but have had some success out to 600 yards).

You’re listing shape profiles for pointed (Spitzer) type bullets (secant, tangent and hybrid ogive) . There are more shapes than that.

https://www.nrafamily.org/articles/2020/8/24/what-is-an-ogive-profile

View attachment 1025947

For example: Solid bullets for dangerous game rifles may not have much, if any ogive, like these hydrostatically stabilized Woodleigh bullets.

View attachment 1025949

Lever gun Round Nose bullets and 160 gr + RN for 6.5x55 loads are often long with neatly straight sides.

Okay, for clarification purposes, I'm just a target shooter using a bolt action .308.

View attachment 1025948

Stay safe.

 

[Riomouse911]

Gotcha. Tell the guys the caliber your shoot, the rifle and the intended use(s) (200 yds, 600+ etc.) and they’ll be good at offering suggestions for bullets, loads, etc.

Stay safe.

 

[Bcwitt]

For target use, it would be a center of gravity/center of pressure thing. One might be favorable to a different twist or chamber configuration. A spire point shifts the mass rearward in relation to a secant ogive. Center of gravity further to the rear is going to favor a faster twist. This is why some bullets of same weight but different configuration may or may not stabilise in a given twist. A hollow point moves the mass away from bullet axis, thus it is less sensitive to twist.

 

[DynoDan1]

For target use, it would be a center of gravity/center of pressure thing. One might be favorable to a different twist or chamber configuration. A spire point shifts the mass rearward in relation to a secant ogive. Center of gravity further to the rear is going to favor a faster twist. This is why some bullets of same weight but different configuration may or may not stabilise in a given twist. A hollow point moves the mass away from bullet axis, thus it is less sensitive to twist.

Yikes!!
How would I be able to know a bullets center of gravity?
How would I know the pressure generated, other than what is published in reloading manuals? Usually, if they publish pressure data, it's with a completely different rifle and powder.
Since I don't plan on replacing the barrel on my rifle(s) anytime soon, I'm stuck with the twist ratio I got, 1:10 I think.
I'm shooting two rifles, both Savage's, Trophy Hunter 22" barrel, Long Range Hunter 26", .308 bolt actions.
Usually I use 168 gr HPBT/FMJBT of whatever's on sale, quite often Hornady #3037 or polymer tipped BT's of Midway cheapies.
I don't have a clue as to what design they are, secant, tangent or hybrid. Whatever they may be I've had outstanding results and horrible results with everything else being the same.
I primarily use Accurate 2460 @ 40.0 grs with 90% of the brass being Lake City.
I don't sort by weight/volume or even lot #, at least not very often.
Some of the brass has been reloaded many many times, perhaps over 15 times.
I anneal the older brass after every use and discard any that show flaws. Most of the older brass does very well but not always.
I've also used Accurate 4064 and IMR 3031 but the 2460 is what I've used 90% of the time.
In the last 2.5 years I've shot somewhere in the neighborhood of 30,000+ rounds and within the last 4-6 months have had decent results sometimes stellar results even out to 600 yards...but not always. Consistency is really the issue. I don't get the same results every time.
I shoot at about 9000 ft altitude year round, hot/cold weather and everything in between no less than once a week with somewhere between 200-500 rounds per session depending on wind and my old bones being up to the task.
Maybe I'm as good as I'm going to get with what I use and got. How would I know?

 

[DynoDan1]

Gotcha. Tell the guys the caliber your shoot, the rifle and the intended use(s) (200 yds, 600+ etc.) and they’ll be good at offering suggestions for bullets, loads, etc.

Stay safe.

Okay.
Target shooting only. Typically @ 100 yards but I do stretch it out from 200 to 600 yards from time to time.
2 Savage's both .308 bolt actions
Trophy Hunter 22" barrel
Long Range Hunter 26" barrel.
1:10 twist.
Thoroughly cleaned after every session as I reuse my primers and the primer powder used is supposedly corrosive.
Bullets are either 168gr or 150gr, usually Hornady or Speer, FMJBT/HPBT/polymer tipped BT.
Powder mostly used is Accurate 2460 but have tried Accurate 4064, IMR 3031. Have had best results with 2460 only because I've gone through 40+#'s of it over the last 2.5 years.
I have been using 40.0 grs of 2460 mostly for 2 reasons, cost and results. I might get better results if I upped the charge a grain or two but until the availability and cost come down, I'm pretty much sticking with 40.0grs but am willing to experiment via folk's advice.
Anything else I need to let folks know?
My avatar represents a good day at the range as of late. I typically have a little larger groups but not by much.
Is that considered good/bad/???

 

[Thomasss]

Have you ever looked at concentricity and bullet run out?
These two items will considerably improve consistent hits you are looking for. They may even be more important than your powder.

 

[DynoDan1]

No, I have not.
Could you explain more?
Concentricity of what?
What is bullet runout?

 

[Bcwitt]

Concentric means you keep axis of bullet, case & chamber in line. That's what you usually get when you assemble carefully w reloading dies. For a quick & dirty check, roll a cartridge on a flat surface. If the tip of bullet appears to wobble, it is not concentric.

 

[Bcwitt]

Center of pressure is a rocketry term, but also used in projectile ballistics. Not related to chamber pressure. It deals w stability of a rotating object.

 

[JFrank]

Have you ever looked at concentricity and bullet run out?
These two items will considerably improve consistent hits you are looking for. They may even be more important than your powder.

I guess we have had different experiences with concentric or lack there of ammunition, do you subscribe to the in bore yaw theory ?

 

[BWS]

30,000 rounds through 2 rifles? How many barrels?

 

[Varminterror]

The center of pressure vs. center of gravity implication is largely described within the aspects of aerodynamics between secant and tangent ogives, so pontificating about academic differences here is wholly summarized in their difference in ballistic coefficient. Secant ogives can typically be more aerodynamic than tangent ogives, and hybrids fall in between.

Ogive profile (secant, tangent, and hybrid - which has a tangent approach junction to the bearing surface but an elongated ogive radius more common to secant ogives) is a MUCH MORE CRITICAL variable in how the bullet is introduced to the lands.

VLD bullets, as an example, have the reputation for preferring to be jammed into the lands due to their secant ogive. These bullets are less likely to allow the lands to center and correct the axis of the bullet, so we introduce the bullet to the lands manually. The longer tip length, however, enabled by a Secant ogive, makes for a very aerodynamic bullet with very efficient form factor (high BC).

Tangent bullets sacrifice some ballistic coefficient to have a smoother transition from ogive into bearing surface, and tend to be more forgiving of bullet jump to lands. The smoother transition from ogive to bearing surface allows the bullet to better center itself on the bore axis. However, this conventionally sacrifices some form factor as the ogive is shorter, and we lose a little efficiency in our BC.

Hybrids have a tangent transition, but a longer radius ogive, so they retain a high BC, but with a more forgiving transition to smooth the bullet’s introduction into the rifling and are more tolerant of varying jump to the lands.

 

[DynoDan1]

30,000 rounds through 2 rifles? How many barrels?

Just the one's they came with.
A friend who is an expert gunsmith (level 7?) looked at them about 8 months ago and said they were fine, just some minor wear at the throat on the oldest rifle.
I bought the Long Range Hunter because another guy at the range said my Trophy Hunter's barrel was shot out.
I bought a rifle bore camera and it indeed looked bad. My gunsmith buddy said to try his favorite barrel cleaning solution, Hoppe's #9 foaming bore cleaner (traditional), let it soak for a 1/2 hour to 45 minutes. I cleaned the barrel as he said and it came out looking brand new which he confirmed and said my barrel was fine. So I bought another rifle because a guy said I needed a new barrel and it turned out I didn't.
It shoots fantastic!!! Better than when it was new.
I clean them both after each outing because I reuse my old primers with a powder mix that is supposedly corrosive. I don't perform a total, complete, thorough cleaning, just enough to remove the corrosive elements from them. I do the full complete cleaning process about every 2nd or 3rd outing, about 1000-1500 rounds total or every 500-700 per rifle. I switch back and forth between them to let them cool down. I also shoot my handguns in between as well.

 

[DynoDan1]

Center of pressure is a rocketry term, but also used in projectile ballistics. Not related to chamber pressure. It deals w stability of a rotating object.

And how does one go about checking bullet stability while in flight through a rifle barrel?
How doe one correct for bullet stability?
How does one determine that poor bullet stability is occurring?

 

[DynoDan1]

Concentric means you keep axis of bullet, case & chamber in line. That's what you usually get when you assemble carefully w reloading dies. For a quick & dirty check, roll a cartridge on a flat surface. If the tip of bullet appears to wobble, it is not concentric.

Okay, I've actually done as you described about rolling my completed cartridges to check for that wobble. I also have a gauge that I use to check for concentricity and have used it for that on occasion. Everything seemed in order, however I don't check every round, just every so often.

 

[DynoDan1]

The center of pressure vs. center of gravity implication is largely described within the aspects of aerodynamics between secant and tangent ogives, so pontificating about academic differences here is wholly summarized in their difference in ballistic coefficient. Secant ogives can typically be more aerodynamic than tangent ogives, and hybrids fall in between.

Ogive profile (secant, tangent, and hybrid - which has a tangent approach junction to the bearing surface but an elongated ogive radius more common to secant ogives) is a MUCH MORE CRITICAL variable in how the bullet is introduced to the lands.

VLD bullets, as an example, have the reputation for preferring to be jammed into the lands due to their secant ogive. These bullets are less likely to allow the lands to center and correct the axis of the bullet, so we introduce the bullet to the lands manually. The longer tip length, however, enabled by a Secant ogive, makes for a very aerodynamic bullet with very efficient form factor (high BC).

Tangent bullets sacrifice some ballistic coefficient to have a smoother transition from ogive into bearing surface, and tend to be more forgiving of bullet jump to lands. The smoother transition from ogive to bearing surface allows the bullet to better center itself on the bore axis. However, this conventionally sacrifices some form factor as the ogive is shorter, and we lose a little efficiency in our BC.

Hybrids have a tangent transition, but a longer radius ogive, so they retain a high BC, but with a more forgiving transition to smooth the bullet’s introduction into the rifling and are more tolerant of varying jump to the lands.

HOLY CRAP!!!
Are you a ballistician?
Excellent info but how do I determine if a bullet is a tangent, secant or hybrid if the info on the box or website doesn't say?
Or does knowing not really matter?

 

[Bcwitt]

No, not a ballistatician. It wont matter a lot. You might find a different chamber likes a particular type. Is very much a trial & error thing.

 

[Bcwitt]

It's a good idea to check every one. You can sort factory ammo the same way & cull the fliers. Wolf ammo is much better then most folks realize. Just separate the crooked ones.

 

[Thomasss]

Rolling a cartridge on a table, piece of glass or mirror is very difficult at best to determine concentric cartridges. And even then what do you do when you find one? The industry standard is .001-.002. That is going to be very hard visually to determine. Use your concentricity gauge and you will find it in a hurry. What's more, you will be able to correct the bullet alignment quickly. In most cases I can reduce out of round bullet seating down to .0005. If you want consistency, every bullet counts. So do them all. Welcome to the "dark side" of reloading. "Use the force Luke; use the force".

 

[DynoDan1]

No, not a ballistatician. It wont matter a lot. You might find a different chamber likes a particular type. Is very much a trial & error thing.

Trial and error!
You'd think after a bazillion rounds I'd notice a pattern, trend or something!!!

 

[DynoDan1]

It's a good idea to check every one. You can sort factory ammo the same way & cull the fliers. Wolf ammo is much better then most folks realize. Just separate the crooked ones.

Dang!!
Checking every one is gonna be a bummer, especially when I do around 500 every week!!!
Good thing I'm OCD!!!

 

[DynoDan1]

Rolling a cartridge on a table, piece of glass or mirror is very difficult at best to determine concentric cartridges. And even then what do you do when you find one? The industry standard is .001-.002. That is going to be very hard visually to determine. Use your concentricity gauge and you will find it in a hurry. What's more, you will be able to correct the bullet alignment quickly. In most cases I can reduce out of round bullet seating down to .0005. If you want consistency, every bullet counts. So do them all. Welcome to the "dark side" of reloading. "Use the force Luke; use the force".

I agree but it can show you one that is seriously out of wack.
How do I correct a wobbly round?
Man!!! I really didn't want to start crawling down that rabbit hole but I guess if I want more accuracy I gotsta just do it!!
My "force" got used up a "long long time ago". Now it's Geritol and Miralax!!! (Yummm)