Jump to content
308AR.com Community
  • Visit Aero Precision
  • Visit Brownells
  • Visit EuroOptic
  • Visit Site
  • Visit Beachin Tactical
  • Visit Rainier Arms
  • Visit Ballistic Advantage
  • Visit Palmetto State Armory
  • Visit Cabelas
  • Visit Sportsmans Guide

Need help with reloads


fr3db3ar
 Share

Recommended Posts

I'll try to include all the information I can.  I just purchased a DPMS Oracle 7.62.  I can chamber a commercial 150 gr 308 that I have lying around but my reloaded stop enough to not fire.

I'm reloading once fired  LC  73 cases.  With a micrometer I can't really find any difference in the two rounds.

Reloads fit the mag easily ( a little under 2.8)  Case length is on.  Base to start of taper is right on.  All diameter dimensions are right on.  The most I find different is about .003 from the base to the top of the taper (base of neck) 

Is this enough to stop my ammo from seating all the way in the chamber?

I'm open to all tips.

BTW I also have a hard time chambering these rounds in my 308 Savage.  I have to tap the bolt handle down to finish the seat.

Link to comment
Share on other sites

If those are tight chambers (I know that Savage is), then that 3 thou is enough to cause what's happening to you.  <thumbsup>

Those LC cases are set up for a military 7.62x51 chambering.  When you do your reloading, are you using a full-length sizing die for .308 Win?

Link to comment
Share on other sites

Yes I have a 2 piece fs die set.  I just checked my die and reset it correctly for fs sizing.  A brand new 308 empty win brass will seat fine, but this brass resized will not.  I have to knock them back out of the chamber and they have a dent in the neck.  What does that mean?

Link to comment
Share on other sites

Well that was a newb question that even I could work out.  I used to be a carpenter by trade so .001 is a little new to me.   I'll have to buy a trimmer for this brass.  .008 apparently makes a big difference.  :)

"Kerf" - with a blade, that's not much.  Here it is, though...  <thumbsup>

8 thou is a giant difference in this stuff.  Just sayin'...

More experienced reloaders will probably get in here on this subject, hopefully.

Link to comment
Share on other sites

You just tried these reoads in a new rifle, so I take it that before reloading, those rounds were shot out of a different rifle?  Bolt or semi auto?

If you are using reloads previously shot out of a different rifle, so, unless you properly full length resize, that brass you use is going to be fireformed to the dimensions of the chamber in the other rifle. 

I just checked my die and reset it correctly for fs sizing.

Meaning?  Was it not set correctly? 

A brand new 308 empty win brass will seat fine, but this brass resized will not.  I have to knock them back out of the chamber and they have a dent in the neck.  What does that mean?

That means the brass was jammed into the chamber, and the chamber was probably tight enough that to try to seat, the bolt the neck got pinched to ram it in.

With a .308/7.62 x 51 the round does not seat off the rim; it seats off of the shoulder of the case.  The "datum line" is the critical dimension (a point about halfway down from where the case neck starts its taper to where the neck taper stops).  Overall case length is not unimportant, but proper headspace is what its all about.

What kind of chamber does you new rifle have, versus your old rifle?  Are they both .308 or is one a 7.62 chamber?  Is it a match chamber, Obemeyer, etc.?  The reason I ask, is that while a .308 will chamber just about any 7.62 x 51 round, because of the small differences between the two, a .308 (designed for chamber pressures of 62,000 PSI) will not necessarily work in a 7.62 chamber (pressures of 50,000 PSI).

If you really want to nail it, take a couple of newly fired cases from your new rifle and send them to Hornnady or Forster (I think Forster will do it).  They will ream your dies to the actual dimensions of YOUR chamber. 

If you reload, and especially if you are reloading for more than one .308, you need to grab something like this:

http://www.jprifles.com/1.5.1.3.php

Wilson also makes them.  I like the JP since it does both OAL and headspace. 

Where football is a game of inches, reloading is a game of thousandths and tens of thousands.  That's why your higher quality precision gauges are all calibrated to a margin of error in tens of thousandths or hundreds of thousandths. 

Finally, if you jammed a case in your new rifle hard enough that caused you to have to knock it back out from the bore, check our your chamber.  Some guys run a Q-Tip in there to see if there is any snag to the cotton.  If there is, or if the chamber is scratched, you may need to get the chamber polished to remove the blemish.

Welcome to the world of reloading!  A true lifetime learning process! 

Link to comment
Share on other sites

First , whats manufactures dies are you using ?

Most ,if not all ,the base of the sizing die must make contact with the shell holder ,when the ram is at its top of its travel & lock it down there , that will give you proper head spacing .

You can get a cartridge head space gage if you want to check it , but that's the way my RCBS dies instructions read & have been doing it that way for over thirty years with no problems.

The cases after sizing , need to be trimmed to length , measurements will be in your reloading manual (you do have at least one ,right )

The case , if once fired or from a different chamber , will make a big deference in its ability to chamber ,because the case will be too long , if not trimmed  & COL will have nothing to do with it .

You will find that after the case is sized & trimmed ,the next sizing ,it will not need much if any at all trimming.

The proper sizing & trimming will make your reloads chamber correctly .You can size & trim a case & see if it will chamber & you will know if you got it right.

Right as far as the case is concerned . If after the emty case chambers & you loaded one doesn't , look to your COL as the problem & different bullet configurations may need to have the COL adj.

You can download this:

http://308ar.com/PDF/head_spacing.pdf

Link to comment
Share on other sites

Thanks for all the good advice gentlemen.  Hopefully I'll have it all worked out in a week or so.

Fred, I believe we are from the same area. If you want to test drive some measuring devices I can help you out. I know some people like to play with stuff before they buy it.

Link to comment
Share on other sites

  • 1 month later...

Actually I solved my problem by full length sizing my brass.  I wasn't shooting 308 through it I just had some lying around that I tried chambering.  I'm using 7.62 brass.

Same dimensions , the 7.62 may be a thicker case . I weigh all my brass & sort it that way .

You may be surprised that even brass of the same head stamp (commercial or milspec ) may have variances in weight & that will change pressure because of the thickness of the brass its self.

Link to comment
Share on other sites

I got all that from a lot of previous reading.  I'm actually pretty excited now with a 175 and a 150 load that shoot with 1/4 moa @ 200 and 1 moa @400.  All approximate but good enough to hit clay pigeons at those distances tonight with both loads. <thumbsup>  now to work out the 223.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...