.303

Foxamaphone

Foxamaphone

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Hey guys,

Can you load a .303 with a .308'' diam. bullet, I know .303 usually uses a
.311" or .312" bullet but I've heard that you can the .308". I just want to make sure before I potentially buggar up a bunch of rounds.
 
what's the point- have you got a lot of 308 bullets or just want to try it- chances are unless you use a 308 die, the 303 brit die won't compress the neck enough to grip the 308 bullet- sure, you can use it, but the bullet will touch NOTHING on the way down the tube - ie a SMOOTHBORE- IN ORDER TO USE THE RIFLE EFFECTIVELY, YOU HAVE TO MATCH THE BULLET DIAMETER TO THE BORE -IT'LL SHOOT LIKE A WASH-OUT BORE - WHERE THE HECK ARE ALL THESE QUESTIONS COMING FROM- JUST LAST WEEK WE HAD A GUY WANTING TO USE 308 IN A 303- THEN BEFORE THAT A 44 -40 IN A 410- I FEAR WE'RE GONNA SEE A LOT OF DARWINS THIS YEAR
 
[SMOOTHBORE- IN ORDER TO USE THE RIFLE EFFECTIVELY, YOU HAVE TO MATCH THE BULLET DIAMETER TO THE BORE -IT'LL SHOOT LIKE A WASH-OUT BORE - WHERE THE HECK ARE ALL THESE QUESTIONS COMING FROM- JUST LAST WEEK WE HAD A GUY WANTING TO USE 308 IN A 303- THEN BEFORE THAT A 44 -40 IN A 410- I FEAR WE'RE GONNA SEE A LOT OF DARWINS THIS YEAR[/QUOTE]

WOO HOO darwing lets put natural selection to the test :popCorn::D
 
Some .303s shoot .308 diameter bullets just fine, others don't. There was a fair amount of variation in actual bore diameter in these rifles. Try it. It certainly won't harm anything and you won't become a contender for a Darwin award.

http://www.public.asu.edu/~roblewis/SMLE/IIID2a11a4.html

This is a good place to start.

T-star: YOU SHOULD HAVE A CLUE OF WHAT YOU ARE TALKING ABOUT BEFORE YOU GO YELLING AT PEOPLE.
 
BCPilotguy said:
Some .303s shoot .308 diameter bullets just fine, others don't. There was a fair amount of variation in actual bore diameter in these rifles. Try it. It certainly won't harm anything and you won't become a contender for a Darwin award.

http://www.public.asu.edu/~roblewis/SMLE/IIID2a11a4.html

This is a good place to start.

T-star: YOU SHOULD HAVE A CLUE OF WHAT YOU ARE TALKING ABOUT BEFORE YOU GO YELLING AT PEOPLE.
Click to expand...

i've been at this coming on 40 years- i KNOW WHAT a bore diameter is and what i'm talking about- the MAJORITY OF THESE RIFLES RUN 311 DAIMETER so i DO HAVE A CLUE AS TO WHAT I'M TALKING ABOUT- i was referring to the amount of questions we've fielded of late of "what happends if i fire this in that " and if you look at the smaller print, i say he CAN- it's there right at the BEGINNING- he might have problems reloading the bullet into the case, but there's NO PROBLEM WITH THE BORE DIAMETER- however, if the bullet is 308 AND THE BORE IS 311 you're going to get the smoothbore effect
 
I too, have heard of good results from shooting .308 size bullets in a 303 British. This comes about because the diameter of the bullet expands on shooting. There is a fancy name for it, but I have trouble getting my tongue around it, let alone trying to spell it!
Years ago I used to regularilly borrow a book from the local library, all about expirements the British had done with the 303 Lee Enfield, well before WW2.
This was long before chronographs, and they actually gave instructions on how to measure bullet speed, with a home built pendelum! (Worked backwards from hitting power.)
One of their expirements was cutting a barrel ever shorter, and testing the results. As they worded it, they cut the barrel so short, as to have a portion of the bullet exposed, when it was chambered! They were surprised to find that the portion of the bullet that stuck out had enlarged to a larger diameter than the bullet originally was.
This, they said, proved that on firing, the the back of the bullet started going before the front portion did.
 
There is a difference between bore diameter and groove diameter. .303 British rifles are typically .302"/.303" on the bore, .311"/.312"/.313" groove diameter. There can be variations, of course, from manufacture or wear.
A .308 diameter bullet is not going to go through a .303 British barrel as if it were a smoothbore. There will be at least .005" interference fit. Might shoot OK, might not. Wouldn't take too many rounds to find out. No reason for this to be dangerous.
It might be necessary to change the expander plug for .308" bullets to be held firmly in the sized .303 cases. Or, the .303 cases could be sized without an expanding plug. That should leave the necks small enough to hold the .308 bullet.
H4831 - Its called upset. Flat based bullets are more likely to upset than boattailed ones.
 
From personal experience:

.303 Britishes will ALL shoot .308 bullets safely. You will want a .308 expander ball to use in place of the slightly larger original one (preferred) or you will need to crimp your rounds (or both).

They will ALMOST ALL shoot them with a reasonable degree of accuracy (though, rarely as accurately as a .312 or so bullet) - and by reasonable, I mean, it should go minute-of-Nazi at 300 yards, I don't mean sub-MOA.

If you can find a 303 with a 2 groove bore, it will probably shoot .308 bullets just as accurately as .311/.312 bullets. This is because the 2 groove bore is almost all bore and nearly no groove - effectively swaging the .308 (or .311 or .312) bullets down to .303 over 90% of the bearing surface and extruding the bullet into the small .312 grooves, thus creating a near-perfect fit regardless of initial bullet diameter being .308 or .312.

I shoot .308 bullets (Winchester 180 grain PowerPoint's) fueled by Win760 in both of my current 303's (one of which is a 2 groove), and I get sub-2MOA with both of them. I do get better accuracy with both guns when using .312 bullets (about 1 to 1.5MOA)
 
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t-star said:
what's the point- have you got a lot of 308 bullets or just want to try it- chances are unless you use a 308 die, the 303 brit die won't compress the neck enough to grip the 308 bullet- sure, you can use it, but the bullet will touch NOTHING on the way down the tube - ie a SMOOTHBORE- IN ORDER TO USE THE RIFLE EFFECTIVELY, YOU HAVE TO MATCH THE BULLET DIAMETER TO THE BORE -IT'LL SHOOT LIKE A WASH-OUT BORE - WHERE THE HECK ARE ALL THESE QUESTIONS COMING FROM- JUST LAST WEEK WE HAD A GUY WANTING TO USE 308 IN A 303- THEN BEFORE THAT A 44 -40 IN A 410- I FEAR WE'RE GONNA SEE A LOT OF DARWINS THIS YEAR
Click to expand...

Well mayby these questions are coming from people that are just getting started into relaoding and don't know, I don't really care if you have 40+ years experience, mayby you think about a few things before you go off with some smart alleck responses, I know there is obviously a slight difference between diam. of the .308 and the .303 but as I had said previously, I was told by someone at a gun shop that it would work.

I was hoping for bare bones, yes or no answers, and if you think I'm an idiot for posting a question like this, and should end up in on the Darwin awards, THEN DON'T POST A REPLY!

I have ZERO tolerance for arrogance!
 
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"...a .303 Savage and it absolutely requires .312 diameter bullets..." It's shot out. The .303 Savage uses .308" bullets. The '.303' part of the name is marketing.
A .308" bullet is the wrong diameter for a .303 British, period.
 
t-star said:
i've been at this coming on 40 years- i KNOW WHAT a bore diameter is and what i'm talking about- the MAJORITY OF THESE RIFLES RUN 311 DAIMETER so i DO HAVE A CLUE AS TO WHAT I'M TALKING ABOUT-........ if the bullet is 308 AND THE BORE IS 311 you're going to get the smoothbore effect
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t-star, the bore diameter is not .308, it is 303! You are confusing bore diameter with groove diameter. Just try forcing a 308 bullet down the barrel of any 303 you can find, and you will soon discover that.


Like others have posted, I have also shot 308 bullets in 303 Br with very acceptable hunting accuracy.

Ted
 
speer no 11, page 254 , second paragraph- "case capacity and case shape of the 303 british cartridge are very similar to those of the 30-40 krag, the 303, however, takes a BULLET OF .311 diameter- the LYMAN manual also says .311 for jacketed and cast
 
t-star said:
speer no 11, page 254 , second paragraph- "case capacity and case shape of the 303 british cartridge are very similar to those of the 30-40 krag, the 303, however, takes a BULLET OF .311 diameter- the LYMAN manual also says .311 for jacketed and cast
Click to expand...

t-star; No one is arguing that the 303 British dies not have a slightly larger bore diameter than does a 308. What was asked was: Can I shoot 308 Diameter bullets in my 303 British? The answer is yes, you can. The bore diameter of the 303 British is .303", a 308 Diameter bullet is nominally .308". That is approximately .005" larger than the 303 bore. This means it will engrave plenty to give it the spin required for fair accuracy, no "smoothbore" effect. You will have a devil of a time trying to push a jacketed 308 bullet down the barrel of a 303 British, trust me. I've been at this business since 1965, and we shot hundreds of .308" diameter bullets in our 303 Brits over the years. Sometimes we could not get .311 - .313 diameter bullets for reloading at all. Results were most often entirely satisfactory with the slightly smaller bullet, particularly the flatbased variety, since the upset occurs to seal the grooves off better. Take it on the chin, apologize and move on. Everyone makes mistakes. It's how you act when you find out it's a mistake that proves your mettle. Regards, Eagleye.
 
Okay, you guys are even screwing up experienced .303 and .308 loaders.

I load .308 in my .308 ( and 30-06 etc) and .311 and .312 in .303 British. The .303 British has LANDS of .303, but the grooves are way deeper. I have a LB with lands of exactly .303 and grooves of .319! It was named .303 using the old system of naming based on the lands, not like modern rifles that name based on the grooves.

The .303 British does shoot larger bullets than the .308! So, you can shoot .308 in .303, it will just be a tiny bit loose.

Just resize your .303 case and put a .308 bullet in it and you'll see - it falls right into the case - I know - I've done it.

So...

.308 = .308
.303 British = .311 (sometimes .312+)

REALLY.
 
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Eagleye said:
t-star; No one is arguing that the 303 British dies not have a slightly larger bore diameter than does a 308. What was asked was: Can I shoot 308 Diameter bullets in my 303 British? The answer is yes, you can. The bore diameter of the 303 British is .303", a 308 Diameter bullet is nominally .308". That is approximately .005" larger than the 303 bore. This means it will engrave plenty to give it the spin required for fair accuracy, no "smoothbore" effect. You will have a devil of a time trying to push a jacketed 308 bullet down the barrel of a 303 British, trust me. I've been at this business since 1965, and we shot hundreds of .308" diameter bullets in our 303 Brits over the years. Sometimes we could not get .311 - .313 diameter bullets for reloading at all. Results were most often entirely satisfactory with the slightly smaller bullet, particularly the flatbased variety, since the upset occurs to seal the grooves off better. Take it on the chin, apologize and move on. Everyone makes mistakes. It's how you act when you find out it's a mistake that proves your mettle. Regards, Eagleye.
Click to expand...

I was impressed by this Eagleye, your words here do as much to persuade me not to lambaste t-star as I'm sure they will to help him accept his stubborn mistake.
 
Enfield rifling

The real specs on the 303 has grooves of .0055, P-14 have .0058 grooves. This all adds up to over the .311. How ever the Enfield rifling is half lands and half grooves giving you a much tighter bore than much smaller lands of most rifles.This is why the 308 bullets should get the spin needed.
 
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