308 diameter projectiles; how to tell for which caliber?

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mesooohoppy
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308 diameter projectiles; how to tell for which caliber?

Post by mesooohoppy » Mon Sep 23, 2019 7:44 pm

I've been reloading for the last 6 months or so on a 550c. I started with 9mm and graduated to 556/223 (figured it would be a good way to learn). I have no one locally to help me as I shoot with one other person (who does not have a desire to reload).

The next caliber I started collecting for is 308. I have everything I need (sans case gage) and will be diving into 300blk shortly.

Here is my problem. I go to a store like midsouth to look for 308 projectiles for starting a 308 winchester load and I cant tell if these bullets are for 300 blk, 308 win, or other 30 cal cartridges:
https://www.midsouthshooterssupply.com/ ... nt-308-dia

Is there a way to easily identify what caliber these projectiles are destined for? I searched and all I found were threads of people arguing about .308-.310 projectile diameter and what the x35 and x51 mean when talking 7.62x35 and 7.62x51 (day one shit).

While not ideal, is there a way to tell which will work with both 300blk and 308 win? I'm not shooting with a can on any of my firearms, so I was thinking 165-168gr projectile as that's what my bolt 308 likes. I'm not sure if that will put me in supersonic territory for 300blk though. Basically, I'd like a middle ground projectile to make inventory easy on my end. If I have to keep two separate 30 cal projectiles, so be it. But I atleast need IDing what projectiles are for what caliber.

I also have some hornady 30 Cal .308 150 gr InterLock® SP projectiles I got via a mail in rebate. I'm assuming these are for 308 Winchester. Can I load these for 300blk? Thank you in advance for these silly questions.

Edit:
I also see some moly coated stuff from places like gallant. I'm assuming these are for 300blk as moly coated stuff usually likes slower velocities. Is there an easy way to tell the fps limit without having to contact them?
https://gallantbullets.com/collections/30-caliber

Same with accura? They state "optimized for 300blk", but can they still technically be safely loaded on a 308 load?
https://accuraoutdoors.com/product-category/308/

Edit #2:
I just searched more for "moly coated bullets" and apparently those are not the same thing as what I buy for pistol from the blue bullets. Someone please help me..

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tallburnedmidget
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Re: 308 diameter projectiles; how to tell for which caliber?

Post by tallburnedmidget » Tue Sep 24, 2019 12:44 am

mesooohoppy wrote:
Mon Sep 23, 2019 7:44 pm
I've been reloading for the last 6 months or so on a 550c. I started with 9mm and graduated to 556/223 (figured it would be a good way to learn). I have no one locally to help me as I shoot with one other person (who does not have a desire to reload).

The next caliber I started collecting for is 308. I have everything I need (sans case gage) and will be diving into 300blk shortly.

Here is my problem. I go to a store like midsouth to look for 308 projectiles for starting a 308 winchester load and I cant tell if these bullets are for 300 blk, 308 win, or other 30 cal cartridges:
https://www.midsouthshooterssupply.com/ ... nt-308-dia

Is there a way to easily identify what caliber these projectiles are destined for? I searched and all I found were threads of people arguing about .308-.310 projectile diameter and what the x35 and x51 mean when talking 7.62x35 and 7.62x51 (day one shit).

While not ideal, is there a way to tell which will work with both 300blk and 308 win? I'm not shooting with a can on any of my firearms, so I was thinking 165-168gr projectile as that's what my bolt 308 likes. I'm not sure if that will put me in supersonic territory for 300blk though. Basically, I'd like a middle ground projectile to make inventory easy on my end. If I have to keep two separate 30 cal projectiles, so be it. But I atleast need IDing what projectiles are for what caliber.

I also have some hornady 30 Cal .308 150 gr InterLock® SP projectiles I got via a mail in rebate. I'm assuming these are for 308 Winchester. Can I load these for 300blk? Thank you in advance for these silly questions.

Edit:
I also see some moly coated stuff from places like gallant. I'm assuming these are for 300blk as moly coated stuff usually likes slower velocities. Is there an easy way to tell the fps limit without having to contact them?
https://gallantbullets.com/collections/30-caliber

Same with accura? They state "optimized for 300blk", but can they still technically be safely loaded on a 308 load?
https://accuraoutdoors.com/product-category/308/

Edit #2:
I just searched more for "moly coated bullets" and apparently those are not the same thing as what I buy for pistol from the blue bullets. Someone please help me..
Hi there and welcome!

Not a silly question for a new handloader at all and this is a good place to get answers :)


In short a 30 caliber bullet of .308 diameter is basically good for a number of calibers for the most part UNLESS specifically specified.
Traditionally .308 diameter bullets are created to be used with the .308, 30-06, 300 win mag, etc. calibers. These traditional bullets generally have a minimum expansion speed of like 1800fps (this is important to remember) and a max speed way up there for like 3000fps+ and such.

The 30-30 also shoots a .308 diameter bullet BUT due to the fact that 30-30's are generally tubular magazine fed the bullet is designed to have a flat tip or round tip and large meplate to avoid one round banging against the primer of the next round in the tubular magazine and causing the primer to fire the bullet in the magazine lol. So these bullets are designed differently AND due to 30-30 lower speeds they may have a lower minimum expanding velocity (lets say 1600fps) but might not.

The 300BLK can fire ANY .308 diameter bullet AS LONG as it can feed and chamber.

Those other calibers can ALSO fire any .308 diameter bllet AS LONG as it can feed and chamber, but why shoot a 30-30 shaped bullet (generally not designed to be efficient at long distances) when you can pick a better designed .308 bullet (pointed bullet, bullet with boat tail, not a cast lead bullet, etc.)


NOW with all of that said. SOME bullets are specifically designed for the 300BLK. The 300BLK designed bullets can generally feed in an AR rifle and magazine with little to no issue AND generally expand at lower minimum velocities (1600fps, 1400fps, etc.) and are generally in lower grain weights that fly faster with the limited 300BLK case capacity for powder. On the flip side some of these 300BLK designed bullets may actually deform or come apart or not handle high velocities so they would NOT be good in the .308, 30-06, and 300 win mag loads as they would come apart or never stabilize well in flight lol.


Depending on your shooting application you can shoot bullets that work with both your .308 and 300BLk calibers. For example, for paper punching or plinking you can shoot 148gr-150gr .308 diameter FMJ bullets in both calibers. A number of us do it without issue. The FMJ is not designed to expand so no worries about min expansion speeds and such. Shooting a bullet like this gives you the versatility to load both calibers with the same bullet, BUT only for paper punching/plinking.

If you want to HUNT, well I think the Speer 150gr .308 Gold Dot would be the only bullet I can think of that would work well in both the 300BLK and a .308 caliber rifle because it seems it will expand at the slower speeds that the 300BLK will push a 150gr bullet. The 150gr Gold Dot is a defense bullet designed to expand very quickly and apparently at lower speeds while still working at higher speeds.

If hunting you must understand that most traditional .308 bullets have a minimum expansion speed of 1800fps so knowing that info, the 300BLK CAN use a traditional .308 bullet at weights of 110gr-130gr within 150yds and be able to push it fast enough to hit minimum expansion speeds for hunting. Once you get near or beyond 150 yards the bullet will likely act like an FMJ and just pencil through whatever it hits which is not what is desired for hunting.

There are a number of hunting or law enforcement bullets designed specifically for the 300BLK that will work well in the 300BLK but not in the .308 caliber. The main one is the Barnes Tac-TX blacktip. I believe it expands down to 1400fps so you can get WAY more range out of that bullet at max 300 BLK capable speeds which are around 2400fps for a 110gr bullet.

Lets now address the Gallant bullets. Those are cast lead bullets that are coated with Powder Coated paint. Because they are coated with powder coated paint they should have no issues being fired at 300BLk speeds. See non-Powder Coated (PC) Cast bullets have a different set of rules to play by. If you push a non-PC cast lead bullets too fast in a rifle then lead will get deposited and left behind in the barrel which is not a good thing. The PC paint solves this problem by acting like a copper jacket but instead of copper it's very durable paint coating.
You can shoot any PC cast lead bullets that will feed and chamber in the 300BLK but loading a cast lead bullet also has some different/additional factors that must be addressed. The main one being that cast lead bullets are generally not a true .308 diameter which is ok for firing the bullet BUT the bullet will not properly seat in your brass casing UNLESS you "bell" the mouth of the case open a bit to accomodate the larger diameter lead bullet. If you don't load cast bullets then you don't know this quirk about loading them AND you don't have the Lee universal case mouth belling die on hand so you would need to buy it.
Again you can load and fire Gallant or other PC Cast lead bullets but you need to understand the differences/quirks and properly address them to ensure things work properly.

Now the accuraoutdoor bullets are another "different" animal to understand. Those bullet descriptions specifically talk about being made for the 300BLK. These bullets also describe their MAX operating speeds of 2150 FPS for the 120gr bullet and 1200FPS for the 200gr bullets.
You can use these bullets in your .308 rifle BUT you cannot exceed the MAX FPS for these bullets.
Even in the 300BLk you have to make sure you don't fire the 120gr bullet over 2150FPS so you still have to watch your speeds in the 300BLK. The 200gr bullet has such a lower max speed BECAUSE it is meant to be a subsonic bullet only. The max speed on the 200gr bullet is the clear indicator of being subsonic (1050fp or under is the threshold for subsonic bullets speeds).
Why do these bullets have a such low MAX speeds???? It is likely that these are "Plated" bullets. Plated bullets are a less harcore cheaper manufacturing and design compared to "Jacketed" bullets. Cheaper yes, but with the drawback that they can't handle higher speeds.

RECAP
So to recap, the 300BLK and the .308 caliber can both shoot .308 diameter bullets. The bullet design (min/max speeds, feeding, etc.) will help dictate whether it makes sense to load it in one vs the other or if possible to load in both calibers.

Your shooting application in the 300BLK will let you know what kind of bullet behavior you are looking. Expansion vs FMJ non-Expansion behavior.
Shooting application will also help determine the weight of the bullet you may want to use since. Lighter traditional .308 diameter bullets expand in the 300BLK at 150yds or under AND will work in a .308 but you may not want to shoot 110-130gr bullets in your .308 caliber loads... or you might, who knows.
Plinking means you can shoot a 148-150gr bullet in both calibers with no second thought.
Hunting makes for much more thought.


Do not load those Accura bullets in your .308 unless you load below the MAX FPS and in that case you have to properly deal with lower powder case volumes which can be a bad thing. Can't just load up half the case with powder or you might blow up the gun lol.

The Gallant bullets are PC cast lead bullets. You can load them in both but in the .308 do not push them so fast that they cause leading in the barrel and again powder in case capacity must be reasonable because too little powder for reduced speeds may go boom.

The 300BLK is the most versatile caliber I have ever encountered. You can load from 85gr expanding pistol bullets subsonic, to 110-165gr supersonic bullets, to 190gr-245gr subsonic bullets all in .308 diameter.
Having a different bullet for different shooting application is usually the norm with the 300BLK and you will find that you have some you will never shoot in your .308 rifle (110gr Blacktip for hunting or law enforcment), some you shoot in both (150gr Gold Dot for hunting, 148-150gr FMJ's for plinking), and some you only shoot in your .308 (200gr Sierra Gamekings for Elk hunting, though it would likely work fine as an expensive 300BLK subsonic plinking bullet).

Phew, that was a lot of info. I hope it helps and feel free to ask all the questions you have :)

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Re: 308 diameter projectiles; how to tell for which caliber?

Post by dellet » Tue Sep 24, 2019 11:04 am

Let's make this a bit more simple and accurate.

All .308" diameter bullets are 30 caliber, but not all 30 caliber bullets are .308". Actual bore size or bullet type will determine diameter. Cast and plated will be slightly larger diameter a will some European cartridges like the 7.62x39mm.

The diameter is the caliber, the case it is shot from is the cartridge.

Velocity only matters with cast and plated bullets, there are a very few exceptions to that rule with expanding types. cast bullets can basically melt and the plating comes off some copper plated bullets in the barrel at higher speeds and temps. Or you can push a cast bullet fast enough that it pushes straight through the rifling instead of spinning

Twist rate, bullet spin rate, is what causes most failures. A 110 Varmageddon can easily be shot over 3000 fps in a 30.06, it comes apart in a hot barrel in my 1/5 twist SBR at 2250 fps. The failure is due to a combination of heat and spin and happens with a lot of bullets spun too fast.

There are many bullets of many calibers that are cartridge specific and many times the reason they are cartridge specific will be in the description from the manufacturer. It could be for feeding reasons, or performance, in the case of the 300 Blackout cartridge, it is often both it designed as cartridge specific.
300 Blackout, not just for sub-sonics.

mesooohoppy
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Re: 308 diameter projectiles; how to tell for which caliber?

Post by mesooohoppy » Tue Sep 24, 2019 1:19 pm

Thank you tall burn and dellet, appreciate it. This helps clear up a lot of my confusion.

I will have to look into 148-150gr projectiles and see if I can make something work between the two calibers. I dont hunt, although I would live to try hog hunting one day (if I do, i will buy specific projectiles/ammo for this). I just shoot paper every weekend. Depending on what comes out of those loads will dictate my next move.

Thanks again!

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Re: 308 diameter projectiles; how to tell for which caliber?

Post by tallburnedmidget » Tue Sep 24, 2019 10:43 pm

mesooohoppy wrote:
Tue Sep 24, 2019 1:19 pm
Thank you tall burn and dellet, appreciate it. This helps clear up a lot of my confusion.

I will have to look into 148-150gr projectiles and see if I can make something work between the two calibers. I dont hunt, although I would live to try hog hunting one day (if I do, i will buy specific projectiles/ammo for this). I just shoot paper every weekend. Depending on what comes out of those loads will dictate my next move.

Thanks again!

No problem, glad to help. I'm glad dellet chimed in as well to clarify on some of the info I was throwing out there. I should have been explicitly calling out your .308 and the catridge as the .308 winchester catridge which is not the same as the .308 diameter/caliber bullet lol.

The midsouth shooter link you provided has 150gr FMJ's for $0.18 a bullet as the cheapest 150gr option. The 125gr Speer TNT is $0.15 a bullet and would be great in the 300BLk but I'm not sure how it would hold up in your .308 winchester rifle, it would likely work as long as it didn't enter a realm of being pushed so fast that it comes apart.

Finally, at my local range they don't allow FMJ's on the 100 yd range :( So in such a case the 125gr Speer TNT work AND the 150gr Speer Hot Cor Spitzer for $0.19 a bullet would be the cheapest options for me. A plus to those speer bullets is that you can hunt with with so if you got into hogs you would be set. So that isn't a bad to get a 125gr hunting bullet you can use in both calibers or a 150gr bullet you can hunt with in the .308 winchester rifle and plink with in the 300BLK (maybe at 50yds the Hot cor would expand for hunting with in the 300BLK).

As you can see you start experiencing the versatility with even this little mix and max combo situation. I hope this info helps and leads to plenty of reloading fun! :)

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Re: 308 diameter projectiles; how to tell for which caliber?

Post by blaster » Wed Sep 25, 2019 10:07 pm

good info above.
in reference to the 150 gr Hornandy SP bullets you have. they have been my favorite deer bullet in my .30/06 for many years. my load pushes them around 2900 fps. I also load them in my 300 Blk and 17.7 grs of H-110 pushes them about 2000 fps in the 16" barrels. they shoot good and are accurate. while I have only used them for plinking and sighting in for the expensive Speer Gold Dot bullets, I think they would preform on game if you kept your shots under 75 yds.
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Re: 308 diameter projectiles; how to tell for which caliber?

Post by BOB567 » Sun Sep 29, 2019 3:02 pm

Not meaning to hijkack this thread, but 7.62x39 bullets are listed at .311. I know every bullet listed as .308 might be off a thousandth but 3 thousandths? Anyone use these bullets? 124 gr. FMJ are cheap, but don't want to use them if they are too big.

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Re: 308 diameter projectiles; how to tell for which caliber?

Post by havoc_squad » Mon Sep 30, 2019 9:56 am

BOB567 wrote:
Sun Sep 29, 2019 3:02 pm
Not meaning to hijkack this thread, but 7.62x39 bullets are listed at .311. I know every bullet listed as .308 might be off a thousandth but 3 thousandths? Anyone use these bullets? 124 gr. FMJ are cheap, but don't want to use them if they are too big.
7.62x39 is a cartridge label/designation, that does not tell you the bullet diameter.

The 7.62mm reference is regarding the diameter of the bore at the rifling, not at the widest part of the bore.

The reason why 7.62x39 is .310/.311 and not .308 is the same reason why Apple portable devices and Android devices cannot use the same apps, the Russians wanted to keep their firearms and ammo different from rivals.

It is not manufacturing sloppiness or defect that 7.62x39 are .310/.311.

A .308 Win/7.62 NATO rifle will not chamber a full metal jacketed bullet with more than about +0.0005 diameter (.3085) to it.

.310/.311 jacketed bullets must be re-sized to .308 diameter to be usable in .308 Win/7.62 NATO/30-06/300 Blackout.

Lead formed bullets are a different matter because they are softer metal and allow slightly wider tolerances but at the expense of only usable at slower speeds.

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Re: 308 diameter projectiles; how to tell for which caliber?

Post by BOB567 » Mon Sep 30, 2019 9:56 pm

Thank you for the explanation.

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Re: 308 diameter projectiles; how to tell for which caliber?

Post by Peace » Tue Oct 01, 2019 12:00 am

tallburnedmidget, I vote that as the best post of 2019!!

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