7.62 vs 308 mix up?

[lovetabike]

it's understood that these are different. I have a .308 AR and bought boxed .308 to try out my new build. After a few tweaks it chambered fine. I bought a bulk bag of once fired military marked as .308. I  loaded and seated the bullets to match the .308 boxed shells. BUT, When I went to the range to test they would not chamber fully. I tried some of my Nosler .308 brass reloaded, without powder and primer, but to the same setup as the 'bulk' brass and they reloaded fine. So my question is, could it be that the bulk brass is really 7.62 and not .308? I don't know what the results would be trying to use 7.56 brass in a .308 AR. Would this be the result?

Thanks

[Sisco]

What kind of sizing dies did you use? Always use small base dies in auto loaders especially with once fired brass. 

[lovetabike]

I'm using Hornadys Custom Grade dies. I'm not sure if they are small base or not. I guess I need to do some research. I guess this is lesson to learn #159.. and I'm sure more to come  ...

 

Thanks,

rich

[98Z5V]

Too much crimp will squash the taper on the case, and expand the case - then it doesn't fit.

There could be several reasons, due to reloading steps made in the reloading process.  A case gauge will be the best thing to get, and check the rounds as they come out of the press - if they don't fit in the case gauge, something's going on with your reloading process...

There is no external dimansional difference between 7.62x51 NATO brass and .308 Win brass, so that's not it.

Edited November 13, 2017 by 98Z5V

[survivalshop]

 As above , did you trim the Brass ?  

Improper shoulder set back will cause issues with chambering , it is why the Case Gage was mentioned .

I use LE Wilson Case Gages . 

[mineralman55]

Anyone reloading should get and use a case gauge. Period. Cheapest insurance you'll ever buy.

BTW, I've been reloading semi autos in 5.56, 7.62x51 and 30-06 for 30+ years and have never used a small-based die. I find I don't need them. YMMV.

[lovetabike]

So it looks like I'm flying blind right not not using a case gauge to really find find what the cases I have are.  I see lyman makes one similar to wilsons and its at cabelas so that's probably what I'll get. 

I'm used to a roll crimp and my .308 full sizing dies use taper crimp and I did initally mess up some shoulders.  I think using a case gauge will go a long way to see if my process is good or not.

 

 

[98Z5V]

On 11/13/2017 at 8:35 AM, lovetabike said:

So it looks like I'm flying blind right not not using a case gauge to really find find what the cases I have are.  I see lyman makes one similar to wilsons and its at cabelas so that's probably what I'll get. 

I'm used to a roll crimp and my .308 full sizing dies use taper crimp and I did initally mess up some shoulders.  I think using a case gauge will go a long way to see if my process is good or not.

 

 

I found these combo blocks from Lyman's, at Bass Pro.  Love 'em. 

https://www.lymanproducts.com/brands/lyman/case-prep-tools/case-gauges/ammo-checkers.html

[lovetabike]

Houston  ... we have a problem ...

[survivalshop]

1 hour ago, lovetabike said:

Houston  ... we have a problem ...

  That will do it . I would set the shoulder back some more if its not damaged . If damaged , you can pull the Bullets & re-Size the Case properly & may need to be trimmed again.

  

On 11/13/2017 at 10:35 AM, lovetabike said:

I'm used to a roll crimp and my .308 full sizing dies use taper crimp and I did initally mess up some shoulders.  I think using a case gauge will go a long way to see if my process is good or not.

Not sure what you meant by the roll crimp & Taper Crimp dies . I have found that the Roll Crimp for Bullets with a Cannelure & a Taper Crimp or Lee's Factory Crimp Die on a Bullet with out one . You can use a Roll Crimp on all ,but you really have to be careful.

[hunterbob]

On ‎11‎/‎16‎/‎2017 at 8:10 PM, survivalshop said:

  That will do it . I would set the shoulder back some more if its not damaged . If damaged , you can pull the Bullets & re-Size the Case properly & may need to be trimmed again.

  

Not sure what you meant by the roll crimp & Taper Crimp dies . I have found that the Roll Crimp for Bullets with a Cannelure & a Taper Crimp or Lee's Factory Crimp Die on a Bullet with out one . You can use a Roll Crimp on all ,but you really have to be careful.

I never use a roll crimp on a 308,,,, No crimp  at all is better...Lee makes a special crimp tool that insures the shoulder and case do not deform...called a factory crimp tool. It crimps from the sides not roll crimping; as where a little too much deforms the shoulder causing the carrier to not go into battery

[hunterbob]

On ‎11‎/‎16‎/‎2017 at 8:10 PM, survivalshop said:

  That will do it . I would set the shoulder back some more if its not damaged . If damaged , you can pull the Bullets & re-Size the Case properly & may need to be trimmed again.

  

Not sure what you meant by the roll crimp & Taper Crimp dies . I have found that the Roll Crimp for Bullets with a Cannelure & a Taper Crimp or Lee's Factory Crimp Die on a Bullet with out one . You can use a Roll Crimp on all ,but you really have to be careful.

The silver case gauge indicates it is not sized properly and to do a full length size again, then check it..If you are just neck sizing, this gauge won't work for you.