Rookie question

I ran across a guy selling these on the net: 30cal 168 Gr BTHP

It made me wonder what a 30cal was.

I looked on Hornady's website and it looked like a 30 cal is a 308.

My first question is what is a 30cal.

Then i got to looking at the different bullets. I found: 30 Cal .308 160 gr FTX® (308 Marlin Express) and 30 Cal .308 160 gr FTX® (30-30 Win) . I thought a 308 was a 308 but it seems that I thought wrong. BTW, first time that ever happened.

So my second question is will and 308 cal bullet fit into any 308 case and eventually into any 308 rifle?

Any help is much appreciated.


  • Woke Up Like This
  • Instant Updates
30 cal 168 BTHP are reloading components, the bullet or projectile. I use these bullets for match grade 30/06 and 308 Winchester cartridges. The 168 are very accurate bullet. I buy Sierra bullets from
OK Weber, Eugene OR. Prices are better than Midway's sale prices. And the shipping is cheaper. I usually get my order in 2 days.

OK Weber | Competition Rifle Parts
.308 is the bore diameter the bullets are intended for, not the .308Win cartridge.
AKA 30 or .30 Caliber bullets. Cartridges that use these include, but aren't limited to; 300Savage, .308Win, .30-06, .300WinMag, .300RUM etc.
30-30 is a little different because bullet designs are restricted to flat or round nosed bullets due to the tube magazines most rifles chambered for the 30-30 cartridge have (lever guns). Hornady substitutes a "flex-tip" (FTX) rubber nosed bullet for use in tube magazines to get around the round nose requirement and improve ballistic coefficient.
The different .308/.30/30 caliber bullets you are looking at are different weights and designs, but they are all called for use in a .308" diameter bore (caliber) barrel.
There are also several different bullet diameters for the .30 cal. There is .308, .310, .311 that are readily available commercially. The .311 bullets are generally used in the 303 British at around 150gr. The .310 I use in my AK47 at 123-124 gr. (AKs dont like heavy bullets in my experience).When I first started loading, I found this to be one of the more confusing calibers. I have learned over the years that different diameters are common in calibers. There are a very wide variety of diameters that can be had / made for .30 cal. I hope this helped but have a feeling that it may have just made things even more confusing.
So far what i understand is that a 30 cal bullet will fit down a 308-312 bore. Sounds king of weird to have a bullet smaller than the diameter of the bore e.g. a 308 bullet in a 312 bore. But i guess it works.

What is a 30-30 or a Marlin Express bullet? Are these 308 diameter bullets made fore a specific case? Will these bullets fit in a 308Win, .30-06 case?


Warning using a 311 bullet in a 308 chamber causes premature wear..For instance a ak barrel is 311 but a mini 30 is 308...To get the best accuracy it is best to slug your barrel for diameter and then go from their..Also shooting 308 bullets out of a 311 barrel will cause mouth of case to split about 50% of the time.


I'll try to simplify all this for james, but will probably fail. Jamie6.5 made a good go of it. Bullets that are called "30 caliber" for American guns almost without exception, will actually be .308 diameter. No need to go slugging your deer rifle barrel. Yes, a .303 British will actually be better served with a .311 diameter bullet, but that's the British, and I'll say no more. Any .308 diameter bullet can be loaded into any "30 caliber" cartridge for an American gun. BUT you might not want to, and the finished cartridge may not fit in the gun. Example: The .30 Carbine cartridge can be loaded with a 150 grain bullet, but the cartridge won't fit in the magazine of an M1 Carbine. However, a Thompson Center Contender might shoot extremely well with this arrangement.

Having disparaged the British, I will give equal disparagement to the American way of naming cartriges, and thus adding to James' confusion. Here's a (incomplete) list of cartridges that shoot bullets that actually measure .308 diameter: .30 Carbine, .30 Remington, .30-30 Winchester, .30-40 Krag, .300 Savage, .303 Savage, .308 Winchester (hey!), .30-06 Springfield, .300 Winchester Magnum, .300 Winchester Short Magnum, .308 Norma Magnum (hey!), .300 Weatherby Magnum.

James can actually take his "Marlin Express" bullets (or any other .308 diameter bullet) and load them in any of these calibers and make a functional cartridge, correct for bore diameter on the gun. But (as stated before), he might not want to, because he couldn't fit that cartridge in a M1 carbine magazine, and at the other end of the spectrum, the .300 Weatherby Magnmum would drive that light-jacketed bullet so fast that James might just blow steaks off the shoulder of a deer without killing it. Note that throughout American cartridge history, only two of these cartridges employ the proper ".308" in their names. One that uses .308 bullets actually calls itself a .303 like those quirky British.

James has every right to be confused. And we have every right to be proud to add to his confusion.


Cerberus Training Group - Run the Gun Rifle
Cerberus Training Group
47 Cattle Dr, Goldendale, WA 98620, USA
Arms Collectors of SW Washington Gun Show
Battleground Community Center
912 E Main St, Battle Ground, WA 98604, USA
Albany Rifle & Pistol Club (ARPC) Gun Show
Linn County Expo Center
3700 Knox Butte Rd E, Albany, OR 97322, USA


  • Copeland Custom Gunworks
    5.00 star(s)
    1911 guru!
    Tim Copeland rebuilt and refreshed an old Colt 1911 Gold Cup for me that needed all new springs, new extractor & replaced a loose ejector. Found...
    • Knute
  • 36 Pit
    4.00 star(s)
    Went here this morning. This was my first time shooting on public land in Oregon. The guys from Trash No Land were there as well as other...
  • HighLine Firearms
    5.00 star(s)
    Good prices, interesting items
    I like taking a drive through farm country to this spot... nice selection.
    • kbf64
  • HighLine Firearms
    5.00 star(s)
    Good Friday!
    Had a great first time visit that included a transfer, a special order, and some trading. Can't wait to come back! Also I realized after I got...
  • HighLine Firearms
    5.00 star(s)
    Upstanding Vendor!
    Have worked with this business twice and both times were outstanding! Will definitely keep going to him when I'm up in that area! Shoot, will...
Top Bottom