308 vs 243

[bbutler]

I know that the 308 and 243 are the same case but you hear everyone say that the 308 is the 1000 yd round . My question is will the 243 go the distance that the 308 will, nevermind the bullet size?

 

[BigG]

The way you would figure that out is if the bullets had the same ballistic coefficient. Whatever the target bullet for the .308 would be, if there were an equivalent BC bullet in the .243, the answer would be "yes." However, the grain weight of the 308 bullet would be higher than the same BC .243 so you would have a harder hitting, better carrying bullet in the .308. I HTH.

 

[AStone]

IMO, .243 v .308 = cherries v. oranges.

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Nem

 

[espanola]

I've shot both for over 35 years--previous posters are right. If distance is your sole criteria, it's a wash. The .243 in general will shoot flatter and obviously higher velocity, but, the .308 has a good bit more punch when it arrives!
The 1000 yard remark isn't bull for everyone, but it is for most of us! Just remember what was most US mil's sniper rounds were for years...

 

[Schleprok62]

My question is will the 243 go the distance that the 308 will, nevermind the bullet size?

Yes, it will carry that far. But it's going to be all but energyless. If all you're wanting to do is put holes in paper, it should retain just enough energy to do that. But not much else...

 

[30-06 lover]

The 243 will get there, but put wind into the equation, and the 308 wins hands down. The 308 also has downrange punch the 243 never will.
-Mike

 

[colt.45]

if i had to pick for long range: it would be the .243. flatter trajectory and the 6mm bullets cary the energy better.

 

[dmckean44]

I would say look into 7mm to get the best of both worlds but the ammo costs more.

 

[colt.45]

just did the calculations.

here are the conditions. 80 degrees F 70% humidity. the .243 is a 85 grain speer spbt going 3250 and the .308 is a 168 grain smk going 2900. (i picked the two bullets with the closest balistic coefficience that i knew of)

at 1000 the .243 ends up at -22.0 MOA // ~1660 fps // ~ 660 ftlbs

at 1000 the .308 is doing -28.8 MOA// ~1430 fps// ~490 ft-lbs

i might be off on a few things but it looks to me like the .243 beat it at everything

 

[rangerruck]

the problem with the 243 has allways been the case design. it is inconsistent and spikey, most of the high power /long distance shooters at one time or another used it, then gave it up. they went on to 6 ppc's or 6.5 284's or 6xc's, and the like. they also erode throats pretty fast , because the neck design doesn't cool down the powder plug that is still burning, and moving up through the case, fast enough. A much better round that is faster and flatter, with far better bbl/chamber life is the old 6mm remmy.
another problem with the 243 compared to the 308, is it's velocity let off. MOST 243 lose a much larger percentage of their speed out to the target than the 308. it is during this drop off, the little pressures, heat swells, wind gusts, etc. that can really bump and shift the bullet around, like riding around in the back of a duece and a half.

 

[Schleprok62]

Results

And these are for 500 yards...

 

[Zak Smith]

Nothing wrong with 243 for long-range shooting. Several competitors in the "practical / tactical" long-range matches are using it with the heavy 100+gr bullets, especially the 115gr DTAC. Having the right twist for these heavy bullets is important. It is a barrel-burner, however, with an expected barrel life of not much more than 1000 rounds.

On the 308 case, 260 REM is a good choice, since it is less overbore (and about 2-3x the barrel life of the heavy 243's), but can still shoot high-BC bullets.