5.56x45 vs 7.62x39

lpaalp

Is either round inherently more accurate than the other? Is there a practical reason to prefer one round over the other?

Mobuck

The 5.56x45/223 is far more accurate in generic form than 7.62x39. This is a very broad statement based on the shape of the cartridge cases. Generally speaking, tapered bottlenecked cases are not as accurate as cases with nearly parallel walls.
I have some fairly accurate handloads for the 7.62x39 but have not produced accuracy similar to what's easily accomplished with 223 in similar type/quality rifles.

tsr1965

Generally speaking, the two most accurate cartridges in the world, are formed from those cases, and they are the 6mm, and 22 PPC.

I think to more define accuracy, in this instance, you need to define the platform they are going to be used in(AK, SKS, or bolt action), and/or the quality of the ammunition.

YMMV

Best

Ray B

Generally Speaking, the rifle has more to do with the bullets accuracy than the cartridge.

Cheechako

I'm with the other Ray on this one. There's no such thing as an inherently accurate case size or shape. The venerable 30-30 WCF cartridge can be made very accurate in the right rifle with the right bullet and powder charge. And speaking of the 22 and 6mm PPC, Benchrest shooters have found that the original 220 Russian with its long sloping case and shoulder is just as accurate as it's' offspring.

Ray

Riomouse911

The cost is now similar for cheapo plinking ammo, so there isn't really a savings one way or the other.

I agree that action, barrel, bedding and load make the accuracy of a cartridge. (Technique is also important, but that's the man not the machine) Good equipment makes it easier to get good groups.

If you want an AK-style gun, the 7.62 is very common. For AR-style guns, it's 5.56 you'll find most often. Costs go from the intermediate range of prices to sky-high, the choice is yours. Both will be fun to own and shoot.

charliemeyer007

If you are behind enemy lines a firearm that uses their ammo is handy for resupply. I have no use for either cartridge or the common platform they usually inhabit.

spirits

I like both of them but prefer the 7.62X39mm for hog and deer hunting chambered in a mini-30. I have used the 5.56X45mm in bolt and AR rifles and would say it was more accurate overall than my mini-30. My mini-30 with the right load shot accurately enough for my hunting purposes.

45er

Well, brass tacks or apples and oranges? Key words to question are "inherently" and "accurate", combined. Which negates personal field experience as too open for interpretation.

Best way to tell is in a highly controlled inviro-- an indoor test range using same platform type test firearm, meticulously handloaded with same quality brass make, shape bullet, etc, having all variables reduced to minimum as close as possible to these distinct two cartridges. Gets deep, don'it?

Perhaps a simple ballestic coefficient chart, (that states different distances also, as important), may bring at least an acceptable down range answer?

That all said... how many serious high qualifiers in national matches are using the (venerable) ol' Ruskie round, compared to the 5.56x45? Easy answer there.

45er

lpaalp

quote:Originally posted by 45er
That all said... how many serious high qualifiers in national matches are using the (venerable) ol' Ruskie round, compared to the 5.56x45? Easy answer there.
45er

All things considered or not included in the question, this may be the definitive answer.

Thanks guys--

chiefr

The 7.62x39 can be an extremely accurate cartridge if used in a custom barrel with a known diameter and bullets to match the diameter, thus reloads.

The AKs and SKS suffer from bore diameters ranging from .308 to .311 or more. To compound the problem, ammunition as imported have bullet diameters that vary. Thus the 7.62x39 does not have a reputation for accuracy.

Conversely, most of your ARs have a standard diameter of .223. Most complaints of poor accuracy in ARs are a result of not matching bullet weigh to barrel twist.

On one occasion, I witnessed a shooter who had a custom made bolt gun from a Mauser action in 7.62x39. He shot his own reloads using 155gr Sierra bullets and his groups were dime sized.

beantownshootah

quote:Originally posted by lpaalp
Is either round inherently more accurate than the other? Is there a practical reason to prefer one round over the other?


On the first thing, quick answer is "no". Either round COULD be loaded to a high level of accuracy, *IF* that was your goal. As already mentioned, the 6mm PPC is one of the most accurate match cartridges in the world, and its based on the 7.62x39 case. There is absolutely no fundamental reason why you couldn't get top level accuracy from either 7.62x39 or 5.45x39 if that's what you're after.

However, in PRACTICE, most people are shooting cheap steel case Russian military type ammo in these calibers, and this type of ammo is mostly manufactured for low cost, with correspondingly poor accuracy. Also in practice, the AK-type platforms that people shoot these rounds out of are designed specifically for low cost and high reliability, also again, with correspondingly poor accuracy. On one vs the other, that's going to be more a function of which exact make of ammo you're comparing and in what platform, rather than one cartridge (generically) vs the other.

Bottom line: Both these rounds in commonly available form are perfectly accurate enough for their intended purpose, which is to hit human sized targets at ranges of roughly 200 yards or less. While in theory you could generate match-grade accuracy from either round, that would require actual match-grade loads and a match grade platform to launch the rounds from (eg a bolt action rifle). In practice, if you're after that sort of accuracy, its probably easier to start with something else. . .

EG: There aren't many production bolt guns in 7.62x39 and I don't think ANY in 5.45x39, and I don't think any of the ones that are, are really intended for serious accuracy. (Yes, there was a match-type East German bolt gun in 5.45, but those weren't all that durable, not many were imported into the USA, and they've been out of production for many years now). So if you wanted something like this it would be a strictly custom proposition. Meanwhile, match grade .223 and .308 bullets are easier to come by then their slightly fatter Commie-bloc peers, and match grade platforms *MUCH* easier to find.

On one vs the other, well, for the moment, corrosive 5.45 surplus ammo is cheaper than 7.62x39. That probably will NOT be the case all that much longer. In terms of ballistics 5.45 offers lower recoil, but retains fairly good lethality due to the super-fast bullet. At a first approximation. 5.45 is like .223, it shoots faster and flatter. 7.62 is like 30/30, range is maybe a little shorter, but the bigger heavier bullet is better on medium game.

7.62 guns are quite a bit more prevalent in the USA (and I think still globally) especially since the category also includes highly prevalent SKS rifles and Ruger mini-30s. 7.62 ammo is also typically quite a bit easier to find, and that's likely to remain true for the foreseeable future. There is also a better VARIETY of 7.62x39 ammo on the market. . .you can get soft point hunting rounds of more than one make. I think there are domestic manufacturers of 7.62, or at least some domestically assembled rounds. . .I don't think ANY domestic maker is currently putting out 5.45x39.