bullet interchangeability

airtruck63chev

airtruck63chev

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Question :

can you reload say a 7.62 based rifle with 30 cal bullets, say a 7.62x54r or 7.62.39 with bullets in 30 cal range say 30-30 or 30-06 , 300 savage.

is there a cross over chart or can you match dia and weights and base powder loads from that?
 
7.62x54R and 7.62x39 both use .311" diameter bullets, like the .303 British. Standard .30 calibre bullets are .308" diameter.
 
You can pull bullets from bulk ammo and seat in 123 grain back into a 123 grain designed cartridge that is keeping same weight of projectile is important, i have done steel core ammo and replaced with soft point, just a pain to keep in place with steel cases. Any heavier, pressures go up and bad things happen, any .30 cal (.308) size bullet will fit, but some sks guns have a larger bore in the .311-.314 range where you would need to slug your bore to see what will work. Hornady makes a 7.62 specific bullet, sierra just says use the .30 cal. Also you cant just take out a bullet and cross refrence what will work because you dont know what powder was loaded in the case/ or primer
 
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Lead Loader said:
You can pull bullets from bulk ammo and seat in 123 grain back into a 123 grain designed cartridge that is keeping same weight of projectile is important, i have done steel core ammo and replaced with soft point, just a pain to keep in place with steel cases. Any heavier, pressures go up and bad things happen, any .30 cal (.308) size bullet will fit, but some sks guns have a larger bore in the .311-.314 range where you would need to slug your bore to see what will work. Hornady makes a 7.62 specific bullet, sierra just says use the .30 cal. Also you cant just take out a bullet and cross refrence what will work because you dont know what powder was loaded in the case/ or primer
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could you not base your powder on weight of bullet? ie:220 grain in a 7.62x54r ? work a load up from min load? with say rl 15 or rl 17?
 
.308 to .311 is a big difference for bullet diameter.Load a .308 projectile into a case meant for .311(Lets say 7.62x54r) and you will get poor neck tension, and,the projectile will not obdurate to the bore.That will equal lower pressure and likely key holing of the target.If on the other hand you take a .311 projectile and stuff it into a .308 casing using a powder charge that may be around max for a .308 projectile your pressure will spike . Not only will you have reduced the throat clearance of the neck by .03 but as the bullet obdurate s the pressure will climb.Definitely not a safe practice.Kind of like sucking a golf ball through a garden hose.


Sorry, Wrong analogy kind of like blowing a golf ball through a garden hose.
 
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There are basically NO areas where you can get away with any sort of size interchangeability: if a round says in the manual that it takes a .311 bullet then it CANNOT use a .309 or smaller or even a .312 or larger (I am ignoring those that slug bores: that is an advanced reloading thing, and I say that so someone doesn't measure wrong and at the very least blow their gun up). :eek:

I only advocate one single reload that is a different size than intended: I find the Taurus Judge shoots .451 bullets (45 ACP) way better than the .452 bullets (45 Colt) due to the rifling design; and this is only one 10 thousandths smaller (fractions of a human hair). As said already, if you put .308 into at .311 bore then you are not saving any money or time in the horrid accuracy and problems it causes.

Beyond that, get into your reloading manuals: the advice is there you prevent you from making one of the "I Blew Up My Gun and Hurt Myself" posts here, because of course, we want you to be a successful reloader for the rest of a natural length of life. :)
 
found me a start point , just have to find some proper sized bullets. and i get it that 30 cal is not 7.62 .. but it could be 7.62 nato.. :)
some of you guys should get out without your mom sometimes.. and as far as no interchangeability 30 cal fits alot..
the .311/7.62 fits the 303 British, the 7.7mm Arisaka, the 7.62x54R and, of course, the 7.62x39mm
Thank you for some of your replys
Hornady JRN
BulletWeight 220 grs
Powder Hodgdon Varget
PowderWeight 42.5 grs
Primer Federal 210M
 
airtruck63chev said:
found me a start point , just have to find some proper sized bullets. and i get it that 30 cal is not 7.62 .. but it could be 7.62 nato.. :)
some of you guys should get out without your mom sometimes.. and as far as no interchangeability 30 cal fits alot..
the .311/7.62 fits the 303 British, the 7.7mm Arisaka, the 7.62x54R and, of course, the 7.62x39mm
Thank you for some of your replys

Hornady JRN
BulletWeight 220 grs
Powder Hodgdon Varget
PowderWeight 42.5 grs
Primer Federal 210M
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Yes, but going out with Moma showed us how to write and express ourselves correctly, so there is no confusion as to what we are trying to say.
 
Not all nominally .308 or .311 are really as specified, or a good suit for the rifle. Commercial .311 is often actually .310, for example, and Lee Enfields may often be happier with a .312 or .313. Buy a goood micrometer before you call me a liar.
 
bushwhacker said:
Not all nominally .308 or .311 are really as specified, or a good suit for the rifle. Commercial .311 is often actually .310, for example, and Lee Enfields may often be happier with a .312 or .313. Buy a goood micrometer before you call me a liar.
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There is a good reason why people say you should swage the barrel of old firearms
 
The rule I've always followed is to never go bigger (except with cast) but you can always go smaller (but may see tumbling/reduced velocity).

I've loaded .308" in both my Mosin and P14 with no tumbling or accuracy difference. Didn't chrony it to see how much velocity I lost though. I just wanted to see if they could shoot them accurately if I was ever in a pinch for .310-.312" components.
I used load data for the same weight bullet regardless of if it was smaller or not.
I wouldn't load .310" or larger in a rifle meant for .308" bullets; except cast which I usually use .311" in all my .308" without issue (.30-30, .300WM, and 3 different 308's).
 
7.62mm isn't the unit of measure you need to deal with. Forget metric altogether and think inches. And 7.62mm doesn't mathematically convert to .308" either. Read your manual for the bullet diameter by cartridge name.
 
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