[SgtDog0311]

Ok, This touches on a lot of issues so not sure where to start and just diving-in here. I’ve read where some say my M1A will have .308 stamped on the barrel. Not mine. I called Springfield to check on my weapon using the serial number and found it was produced in Aug of 1985; maps over to their current day “Standard with Walnut stock and they called it a Ma9102”. But when I pressed for more and mentioned reading about USGI parts vs newer models I found that the bolt was USGI (by virtue of the TRW stamp) and that the barrel was a chome-lined barrel chambered for 7.62 vs .308. I had to skirt the reloading gist of my questioning but it relates to dies and which ones I should be aiming at for reloading. I know that Zediker says Small Base is the only way to go, or at least that’s what I get from his article. But I see several on the M14 specific forums who differ. So I’m trying to reason this out. And my reasoning is as follows: if I have a barrel and chamber produced for the looser 7.62 specs, then expansion is greater upon firing. If that is the case, two things should follow. First, the full length standard dies should work the brass less and hopefully be adequate for subsequent chambering and extracting of ammo. Second, if the 7.62 chamber has more tolerance, then a Small Base die would hopefully be overkill and possibly more than necessary or even recommended, when in fact it might be very necessary for a tighter tolerance .308. Am I correct in this line of reasoning? Initially I was considering an RCBS X-Die Small Base. As I read the thread now I am leaning towards the Redding Type S full length sizing die and a Forster Ultra seating die. The delta is significant in dollars (about $130 vs $45) payable now but if I’m getting more brass life, then over time it may well be worth the up-front cost. Thought I’d run that by those on a forum more specific to M-14s. Appreciate the feedback from those way ahead of me on reloading. For the record, I’m not a match shooter and don’t intend to become one. Just want to get back with an old friend I haven’t visited much since boot camp. Also - intend on reloading with Winchester brass, Sierra GameKing (165 grain) and 4895 variety powder. That’s about it for now. Sure there will be more bases upon input from you all. Thanks!!!

 

[stevelish]

Only way to know for sure is to try them both. You shouldn't have any feeding problems with the SB, but you may get away with the standard. You can also get the X-die in standard size as well.
As far as extending brass life, I think safety should trump the minimal economic savings, don't try ty squeeze too much out of your brass in terms of longevity. You can't save enough to replace your face. Having said that, I am using the x die, but only to eliminate trimming.

 

[JayKosta]

When FL-sizing the cases, I think that most people adjust the die so that the cases work reliably in their rifle.
NOT resize all the way back down to 'new case' dimensions.

I'm surprised that the barrel is not marked with the caliber - usually the marking is visible when the oprod is locked back.

Jay Kosta
Endwell NY USA

 

[art luppino]

.308 vs 7.62mm chamber

Given your barrel is not a GI issue barrel it may have a chamber of any size depending on what reamer was use to cut it. First thing to determine is the head space.. With this number in mind, you at least know what the case head space should be.

Deciding on FL or SB sizing dies is a secondary issue.. Why anyone would insist on SB dies before trying the standard FL sizing die is a mystery to me... Using SB dies in the M1A may be required if the chamber was reamed by using a reamer that has been sharpened or a Special reamer used for a Special reason.

I have never see a M1A, M14 or M1 Garand that required the use of a SB sizing die. No doubt there are some out there, but I suspect they were Special chambered or a mistake was made. There are Match shooters that use SB dies because this is a hedge against feeding failures in Rapid fire stages.. Fred Filkins, {USMC** one time top Marine shooter used SB dies because he never cleaned his rifle. Art

 

[SgtDog0311]

Reloading to 7.62 vs .308 Chamber

Jay,
I've missed things before and my eyesight is getting bad in my young/old age but I put the spectacles on and looked careful. Only thing (right under the operating Rod) is a "Geneseo, IL" stamp. I recall your name from threads where I picked up on the 308 stamp clue originally and that's why I looked, and part of what prompted my call to SA. Looked again just now to double check.

Jay and Steve,
Thought I'd start a lively discussion between adherents to one camp or the other here (Small Base vs Standard FL) but guess not. Still wondering if my rational is good regarding the 308 vs 7.62 chamber size and how that impacts advisability for Small Base vs Standard. I might try both in the end but I’ve got to start with one or the other and would hope to guess right for my pocket book’s sake. The SB would for sure work, but if unnecessary I’d rather resize to what slips in without issue. I’m +1 on safety trumping economy (my face has already been mangled by a head-on, so can’t afford any more to that) but if I can have both safety and economy that’s what I’m aiming at. Still interested in what’s being used out there and if it is relative to chambering.

John

 

[SgtDog0311]

For Art

Art... I guess I thought the Chrome Lined and 7.62 meant mine was a USGI barrel. Hows come you to say it aint? John

 

[TheTinMan]

The "small base" die only reduces the diameter of the case, correct? I ass-u-me it's the diameter at the base (or casehead) we are talking about. Can't be the outside diameter of the neck because the bullets are the same outside diameter.

Granted that 7.62 Nato has a slightly longer headspace than .308 Winchester does, I don't know why this means the diameter of the chamber would be smaller for an M-14, M1A, etc.

Is the idea that cases should fit looser in a gas-operated semi-auto than in other rifles?

Maybe the small base concept is due to guys using once-fired military brass that got abused by a machine gun. I think it's safe to assume that machine guns have slightly looser chambers in all dimensions, especially if they're used a lot. Those cases might require an extra push to get the diameter correct the first time you re-size it.

SgtDog - do yourself a favor and get a .308 Winchester Wilson case gauge.

 

[RAMMAC]

...use SB dies because this is a hedge against feeding failures...Art

That's the only reason I use them, I just don't want the thing to quit running. I suspect that it doesn't help accuracy, probably not by much though, but I'd rather rounds come out every time I squeeze the trigger.

 

[John Crusher]

Art... I guess I thought the Chrome Lined and 7.62 meant mine was a USGI barrel. Hows come you to say it aint? John

Did you remove the rifle from the stock and look on the bottom of the barrel? My 5/65 SA barrel on my std. was marked there not behind the op rod.
I use SB dies on my tight chambers and FL on the loose ones.

 

[geepee3]

The "small base" die only reduces the diameter of the case, correct? I ass-u-me it's the diameter at the base (or casehead) we are talking about. Can't be the outside diameter of the neck because the bullets are the same outside diameter.

TinMan,
Small base dies sets the shoulder of the case about two thousandth of an inch back twards the case head. You are working the shoulder more which limits the amount of case reloads.
Glenn

 

[TheTinMan]

Glen - I've done a little more research and you are correct, the RCBS small base dies also move the shoulder back slightly for some calibers, in addition to reducing the diameter of the case below the shoulder. 7.62 Nato appears to be one of those calibers.

What puzzles me about this is that I could adjust my Hornady .308 Winchester sizing die to push the shoulder back past the "no go" point on my Wilson case gauge. However, I don't know why I would want to do that.

Chip

 

[geepee3]

Glen - I've done a little more research and you are correct, the RCBS small base dies also move the shoulder back slightly for some calibers, in addition to reducing the diameter of the case below the shoulder. 7.62 Nato appears to be one of those calibers.

Chip

Chip,
I use Redding small base bushing type dies. Checked diameters on out of the box LC M118 long range cartidges and my sized cases (LC, GGG, FC). And found the resized cases slighty more (.0005") in diameter measure at the same points of the case bodies. Here are some pictures to show you how close new cases and my resized ones are.

cases; PMC, S.B. resized loaded LC, S.B. resized GGG, LC M118, Scharch's resized LC, Federal XM762D.

LC M118, S.B. resized loaded LC.

Closer look at the shoulders. My resized have a larger headspace than the M118.

I cannot say what RCBS S.B. does to the diameters, I know my Redding dies just about match new case diameters.

Glenn