7.62 vs. .308 Brass

MMH

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Is the primary advantage of .308 brass a little more case capacity? What would be the downside of using 7.62x51 brass?
 

GhengisAhn175

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7.62 brass is going to be thicker slightly and internal capacity is lower but it’s negligible.

for 308 I like to use FC mil once fired. Just need to prep and neck turn then you’re good to go.
 

Yondering

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7.62 mil brass does have less internal capacity due to the thicker case walls. The difference is not negligible, you do need to back down your loads a bit if you've worked up a load in typical 308 brass.
 

918v

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It depends on the specific brand of case. Which cases are we talking about? LC vs Lapua? LC vs FC? LC vs “Winchester”?
 

MtnCreek

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^ Yeap.

Downside to milsurp brass is most was stretched out pretty bad on initial firing and most will have crimped primer pockets. It’s good brass for cheap imo.
 

Beneviolence

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If you're reloading for precision, I would go a step further than deciding between 7.62 and 308; I'd stick with a single headstamp/manufacturer. Otherwise, you're going to have drastically different case volumes, pressures, neck thickness/tension, etc.
 

elfster1234

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    I’m a big fan of once fired lake city 7.62! Once you size it and fire form the brass to your chamber and then bump the headspace.001 for bolts and .003-.005 for semi auto = its a moot issue.... yeah, Case capacity is less in 7.62 and I’ll back off the charge from max just the smallest amount (obviously keep eye on pressure signs) but lake city is crazy durable and last very long,,,, especially for semi autos
     

    Lucky Se7en

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    I've always been skeptical about buying fired brass but it seems like there are a lot of people that swear by the LC brass. Are there certain places that are more reputable than others for buying it?
     

    elfster1234

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    This is is by far not my best 6x5 but I ran this with non fire formed beat up military lake city brass out of my tikka



    I've always been skeptical about buying fired brass but it seems like there are a lot of people that swear by the LC brass. Are there certain places that are more reputable than others for buying it?

     

    elfster1234

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    I've always been skeptical about buying fired brass but it seems like there are a lot of people that swear by the LC brass. Are there certain places that are more reputable than others for buying it?

    ill usually just do a little searching on Facebook and the closed reloading groups. Wes sage is a good resource on Facebook but he might not have matching head stamps tho. I got my last batch of 500 pcs 7.62 once fired matching same year head stamp off Facebook shipped I want to say about $50

     

    MMH

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    I knew the case volume was smaller, and if I load, I would work up new loads. Is there a velocity drop for 7.62 vs. commercial brass? Typically, how much is the charge reduction (I will work up my loads from a safe starting load) but just am curious.
     

    918v

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    If you’re going to make blanket statements, there is no difference in volume and no difference in velocity, generally. Reason being that many, if not most, commercial brands weigh as much if not more than military.
     

    Yondering

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    If you’re going to make blanket statements, there is no difference in volume and no difference in velocity, generally. Reason being that many, if not most, commercial brands weigh as much if not more than military.

    Ah, no. Maybe you're confused with 5.56, but commercial 308 brass is almost universally lighter than 7.62 brass by 10-20 grains. Obviously that varies with manufacturers of each, but there is a distinct difference in both weight and case capacity.

    That is not true of 5.56 vs 223, so maybe that's what you're thinking of.
     

    918v

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    Wrong.

    FC commercial cases are identical to LC and FC military. So are GFL, CBC, Perfecta, some Winchester, some Hornady, etc.

    Turkish MKE military 762 are identical to Lapua.

    Got some 164gr HP 11 762 over here...

    There is too much overlap



     

    918v

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    Oh, forgot, PPU has both military and commercial cases that are identical.

    You have to weigh your cases to see to see what you have. You can’t just go off the fictitious 762 vs commercial difference.