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Discussion Starter #1
I just purchased a Winchester 30-30,model 94 (production year 1977) at a local gun show. I own a 1972 Marlin 30-30 too which I cherish and maintain like a new vehicle.

I have "nogo" and "field" headspace gauges and to my astonishment when I inserted the field gauge it fully chambered in this Winchester.

Is this normal for the Winchesters to fully chamber a field gauge....my Marlin which is older and having fired uncountable rounds will not chamber the field gauge.

Thanks everyone.
 

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I knew they existed, but I have never seen a field gage, for any chamber other than a military round. I am not sure a field would be typical, but a generous chamber on a lever gun, is not unusual since the lever has little enough power to close an oversize round. Dont forget, Win was going through QC problems in those days much like Remlin is now, (and most every one else)

I have heard that the term field gage, came from when a military rifle came back to the armory, it was to be taken out of the field, if it accepted that gage. Not certain that makes total logic, but thats the story generally told as too why its called "field".

Headspace is a complicated topic, and a bit misunderstood. Since the 30 30 headspaces on the rim, i would think you would find primer backing out a bit if you fired that gun. Not dangerous unless in the extreme, excess headspace becomes an issue in reloading, more than shooting factory ammo. Again, thats in a typical situation. All sorts of tests have shown, that the round will simply expand out to the limits of the chamber walls. Now if that round is full length resized, and fired, it then generally splits in the chamber, rarely damaging the gun, but a pain in the butt still.

Gun show deals are often final, but you are between a rock and hard place. I would take it back too the guy you bought it from, with the gage, and try to get your money back. There is no easy cure for that issue, seeing as too how Win is out of business. An oversize bolt, if such a thing exists, or a different barrel, or that barrel set back and re chambered, with all the other mods needed to make that possible, mag tube issues etc.
 
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As long as the barrel is in decent shape, head space one a Winchester is a simple fix normally. A new rear locking bolt can normally bring it back into spec. It is a $30 to $40 part that is simple to install.

Keith
 

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Discussion Starter #4
Thanks RGR and Bronco.....think I'll check around and try to locate a new locking slide bolt assembly.

Be safe 'n God bless
 

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As long as the barrel is in decent shape, head space one a Winchester is a simple fix normally. A new rear locking bolt can normally bring it back into spec. It is a $30 to $40 part that is simple to install.

Keith
Could be I guess, but just where does one find an oversize locking bolt for a discontinued 94 Win? How will he know if the new one he gets is going to be large enough to cure the issue? Even if he can find one? How did the old bolt get thinner?
Ya got a part number? :)
 

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It finally occured to me, that we dont really know where the headspace exists. It feasibly could be either wear, or a max cut in the locking bolt ways on the action. It could be a lousy heat treat on the action. The rifle is fairly recent, probably not fired more than a few hundred rounds total, so that puts any major wear on the back of the list.

It could as well be a max cut on the bolt face. It could be a stacking of specifications in all the areas. Most likely its a deep chamber. And even if you can find an oversize locking bolt, though I have seen or heard of one, not saying they dont exist, but unless its an oversize piece, you wont gain anything by simply replacing the existing bolt, as its not likely worn, and you wont know if the new oversize bolt will enter the action behind the existing breech bolt either.

And even if it should, it still wont push the breech bolt any closer too the action by very much, which has limited forward travel by the length of the barrel shank. I dont have a 94 in hand, but they dont have much space between the bolt and barrel in the first place. A few thou maybe.
If the chamber is cut over specs, even if all the above was installed, it still may not be enough to bring it back under field.

I could not find the specs on go versus no go versus field on the 30 30, but according to the RCBS chamber print book, the rim on a SAAMI chamber is between .063/.070 or .007 "go" headspace. Now the ammo print, shows .063/.053 on the ammo rim. So assuming a thin rim of .053 was fired in a .070 chamber, you would end up with .017 of primer back out, and that is still with everything "in Sammi Spec".

Now .017 is "dead nuts" to a carpenter, and maybe "close enough" to a cabinet maker, but too an accuracy gunsmith or machinist, .017 is akin to a four lane highway in size. Too a gage maker, it would be akin too the Grand Canyon.

I guess that explains as too why I have seen so many 30 30s over the years, with primers sticking out. It would appear that they had excess head space, but according to this closer study, no. LIke we have already noted, 30 30 lever guns are noted for having generous chambers across the board.
 

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The two locking bolts I have replaced have come in on the fat side and needed a bit of thinning. I can't tell for sure if they are always this way but that is what I have found.

Keith

Could be I guess, but just where does one find an oversize locking bolt for a discontinued 94 Win? How will he know if the new one he gets is going to be large enough to cure the issue? Even if he can find one? How did the old bolt get thinner?
Ya got a part number? :)
 

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I do not doubt that a bit. All sorts of gun parts come in, that need fitting.:) The question becomes again, whether they were designed that way on purpose, and whether or not they will cure his particular gun.

Guessing, and throwing parts at a gun hoping they will fix it, works at times, and other times it doesnt. Win had more than a few monday and friday guns in those days.

When it gets right down too it, unless he reloads, it wont matter one whit if the primer backs out a couple of thousandths. A lot of 94 Win's do just that.:)
 

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Discussion Starter #9
RGB.......yes I do plan on reloading for my 30-30's but haven't started yet. Powder in my area (New Orleans) is very scarce and impossible to find and until I can find a local source the reloading is on the rear burner. Internet powder is too expensive because of the hazardous material charges since I wouldn't be buying in bulk quantities.

When/if I do find a local source for powder I won't be pushing out "hot" loads since I'm only shooting 100 yard target distances.

Do you think once I start reloading that the pocket cleaning,stainless steel tumbling media and the large headspace combination that there's the possibility of primer ejection and possible physical injuries?

If I have to I'll make a few rounds over max load (when I find some powder) and fire the rifle using a string while I'm safe behind an ole oak tree and see what happens. If it handles "over max" loads then I'll feel safe firing it using the light loads I intend to use. If the rifle disintegrates then my worries are over. I would much prefer losing a rifle then losing an eye or part of my brain (of which seems to be getting smaller as I age)...lol.

Thanks
 

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There are still a few mysterys here. Can you supply a close up picture of the fired case from the gun? There is quite a bit of net nonsense, when it comes to the danger issue of headspace. Guns hardly ever are damaged by a gun with excessive headspace, Where, the damage generally happens, is that the cases simply split into two pieces.

If the headspace is that great, light loads are not going to solve any of the issue. Even a "light" load, has thousands of pounds of pressure. Generally, the closest thing too a cure, is too neck size only, since the case has expanded to full size. And even that may not cure the primer set back totally.

You really are between a rock and a hard place with this gun. You really need to find an experienced rifle gunsmith, to examine the gun in hand and personally. And when you do reload, DO NOT full length size your cases, as that will guarantee a two piece case, on about the second, and maybe even the first reload. Again not as dangerous as some may allege. I have seen forgotten numbers of cases come apart in a chamber over the years, and have never heard of any one being harmed in the least by such.

One last piece of advice, one should NEVER EVER shoot a gun without shooting glasses. Gas coming back is rare, but even with factory ammo, it can happen, though again very rare. Stevie Wonder may get by being blind, but no one should take their vision for granted. And again, dont let the fear of such prevent your from shooting. But one should never shoot with out glasses, even if they do not need corrective lenses.
 
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Discussion Starter #11
I haven't fired this 30-30 yet. The next day after purchasing this rifle I remembered I had the field gauge and that's when I found this mysterious large headspace....and by then the gun show had already hit the road to other events.

All I do is size the necks...never full length. Only full length sizing I do is on bulk "once fired" brass....thereafter only neck size for bullet tension. After a few firings (3-4) and reloads I anneal and resize necks only.

With this newer 30-30 I'll keep the brass independent to each respective rifle by color coding the brass IF necessary which I'm almost positive I'll have to do since this newer rifle's headspace is so large and the spent brass will most likely be "ballooned" further away from the base. As a test whenever I get the chance to shoot this newer 30-30 I'll fire several round from each rifle then neck size and reload then check to see if both rifles will chamber it's "brother" counterpart. I theorize the brass from the newer rifle will jam upon chambering in my older 30-30 and the fired brass from my old 30-30 will chamber perfect in the newer 30-30. Time will tell !

At the range where my son and I shoot it's mandatory to wear eye 'n ear protection. I once had to make a u-turn to get our eye 'n ear gear...and I was like 15 miles away from home. Guess that's what I get when I clean up the gear and not putting it back in it's proper place. My son and I use Remington shooting glasses and Ruger ear muffs.

Thanks RGR
 
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