Head Space gauge VS once fired full lenghted

[eddiesindian]

Curious:
How many of you guys have used a once fired full length sized brass to set head space , then compared your head space adjustment to a head space gauge. What were your findings?

Next question:
How many of you guys reset your initial head space after you've fire formed new brass in that chamber and tried using that same fire formed brass that was neck sized only then used it as a head space gauge. What were your findings?

[FW Conch]

I will respond as follows...the first barrel swap I did was a 308 that I swapped to a 260Rem, bought the head space gauges which were in common. Once I realized what Head Space was all about, as a result of that build, I never bought another set of head space gauges. Head Space is a chamber setting that insures a standard cartridge will fit in it. It doesn't matter how that is done, just so we get it right. The way I get it right, I take a case out of the box of cases that I am going to reload, set the head space to it with the nut hand tight, then see if the rest of the box of cases will cycle through the chamber. If I find one that is more snug than the rest, I reset the head space to that one, and make it permanent. Then I load that batch of cases with the intent of the first firing to be fireformig, although I do shoot for groups to gain all the information I can from that batch. People pay extra money to get tight chambers. Once I fire a case in a chamber, "I have a tight chamber"! From then on I neck size only until my cases will no longer chamber. So far that has averaged out to be about 10 reloads. I can understand bumping shoulders with gas guns, but not bolt guns. After shooting, the first thing I do before packing up is make sure all my fired brass will cycle through my chamber, then I know I am good to go with neck sizing. I don't see any advantage to using a fire formed case to set the head space, and you could end up with a "wildcat" chamber in which a factory load could fail to fire?

There has been so much written about head space, bumping, measuring, special tools, etc., that confusion abounds. It is not that complicated, especially with bolt rifles.

This is how I do it, and I hope I didn't "rant" too far off the questions being asked...Jim :-)

[eddiesindian]

Its good to know Im not the only one doing this then. If I were to be doing this as a trade/smith, Then Id without a dought use a gauge.

[FW Conch]

^ Agreed ^ A trade/smith may be required to prove that the setting was very close to SAMMI specks. That would make it a different ball game.

[Mozella]

What am I missing? I don't get this fascination with using something other than a standard specification gauge for setting headspace. I'm no gunsmith, but I have set headspace a few times when building rifles both for fun and for competition. My technique is to use a SAAMI spec gauge and adjust the headspace so that my gun will barely accept that gauge. It follows that if I buy brass made to the same specification, it should fit. Likewise, if I sell my rifle, the new owner can expect his SAAMI spec brass to fit, ignoring for the moment the questions of neck diameter and bullet seating depth, ammunition overall length, etc. which are subjects for a different discussion.

When I fire my brass it will conform to my standard chamber and then immediately spring back very slightly so that it can be extracted. The next time this piece of brass is reloaded, I make sure it's still a tiny bit smaller than my chamber so that I can close the bolt. In time, may grow to the point where it will no longer chamber properly at which time I can resize it so that it will fit. In other words, typically my new brass and my fired brass are slightly smaller in diameter and shorter in length than my chamber/headspace size. My fired brass just barely fits with the new brass having perhaps slightly more slop, depending on how it was manufactured. But all this is based on a known published standard, assuming the company that made the gauge machined it properly.

I could set my headspace using a piece of brass which is a different size from a standard spec gauge. Why would I want to do that? I understand the desire to make a true wildcat cartridge, but by using a fired piece of brass which is only slightly different from a standard spec gauge, isn't that the same as adjusting my headspace to be out of spec? What is wrong with matching the standard specification?

Of course, specifications aren't sacrosanct All my hand loaded competition ammo is longer than SAAMI specifications since I shoot exclusively single-shot bolt rifles. But all my brass is within SAAMI specifications and my headspace is adjusted to match those specifications. Why would I want to do it differently? Inquiring minds want to know.

[Nor Cal Mikie]

Only one of my rifles/pistols has ever been set using gauges. That was/is a .221 Fireball. And after the head space was reset using the SAAMI gauge, it was reset again to closer specs. Not one of my rigs will chamber factory loaded ammo. Head space is too snug/tight. (I Love It That Way) You move much less brass when resizing. Mostly shoulder bump and neck size. Full length or body size only when/as needed. Brass lasts at least 25 + reloads before I even think about trimming being needed. .223 and .308 for gas guns get full length resized.
All head space is set using full length sized brass. New or resized, makes no difference.
Only gauges I ever used got sold to someone that needed them more than I did.
Not sure if I've ever compared the head space set with resized brass to gauges but I know factory built ammo wouldn't fit in the chamber. That was a good enough comparison for me.
So what it comes down to is, if you're reloading and using resized brass to set the headspace, you're building "custom" ammo. Your's won't fit mine and mine won't fit your's. And custom built ammo is better than any over the counter ammo, any day!!

[bsekf]

Headspace is not the boogeyman! If you have ever fooled with Thompson Center single shots you know that every one of them has a different headspace because of the frame barrel gap. Now how much you bump the shoulder back, thus changing the headspace, will have an effect on accuracy. Some guys FL every round but are very careful to keep the shoulder bump at .001. I am of the school of fire forming and then just neck sizing either with a collet or neck die until I get resistance, then it is time to FL and anneal. Usually 4-5 reloads. FW Counch gave you good advice. Headspace is that measurement from ogive to base so commercial ammo will fit in more than one gun. Never checked, but I'll bet the tolerance is +/- .005. That's why I reload, to reduce the tolerance to as near 0 as possible.

[eddiesindian]

Headspace is not the boogeyman! If you have ever fooled with Thompson Center single shots you know that every one of them has a different headspace because of the frame barrel gap. Now how much you bump the shoulder back, thus changing the headspace, will have an effect on accuracy. Some guys FL every round but are very careful to keep the shoulder bump at .001. I am of the school of fire forming and then just neck sizing either with a collet or neck die until I get resistance, then it is time to FL and anneal. Usually 4-5 reloads. FW Counch gave you good advice. Headspace is that measurement from ogive to base so commercial ammo will fit in more than one gun. Never checked, but I'll bet the tolerance is +/- .005. That's why I reload, to reduce the tolerance to as near 0 as possible.

I wasn't asking for advise or how to,s... I asked specific questions. You may reconsider what you call head space. Base of cartridge (breech ) to shoulder of case is head space. Ogive to base as you've mentioned would be more of a C.O.A.L. if that's where you measure it which is where I do for seating depths. but thanks anyway bsekf. Don't own a Thompson single but I did however purchase there very 1st semi 22LR rifle. Man I love that rifle.

[dpfelton]

I use both methods and neither method is better or more accurate than the other. I have custom rifles and savages in the same caliber. I use the fired brass method so I can use one set of dies to load for two or three different rifles. I measure the headspace of a fired piece of brass, size the body so the headspace doesn't change then install barrel to that brass. My 3-308's and 2-243's all measure the same headspace so I use one redding body die for each of these calibers and never have to adjust the die once set.

Hope this answers your question.

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[eddiesindian]

I use both methods and neither method is better or more accurate than the other. I have custom rifles and savages in the same caliber. I use the fired brass method so I can use one set of dies to load for two or three different rifles. I measure the headspace of a fired piece of brass, size the body so the headspace doesn't change then install barrel to that brass. My 3-308's and 2-243's all measure the same headspace so I use one redding body die for each of these calibers and never have to adjust the die once set.

Hope this answers your question.

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...your using your brass to set head space so basically you've answered my question. Thanks.
about the only thing I do different is that I collet size all my bolt guns. I wont full size until its needed.
having one reloading body for all is a time saver.

[bsekf]

I wasn't asking for advise or how to,s... I asked specific questions. You may reconsider what you call head space. Base of cartridge (breech ) to shoulder of case is head space. Ogive to base as you've mentioned would be more of a C.O.A.L. if that's where you measure it which is where I do for seating depths. but thanks anyway bsekf. Don't own a Thompson single but I did however purchase there very 1st semi 22LR rifle. Man I love that rifle.

Sorry, I misquoted FW Counch's excellent post.

[eddiesindian]

No worries bsekf

[FiveInADime]

I'm a little late to the party.

I just wanted to mention one thing...

When I fire a new piece of brass for the first time the shoulder often doesn't form to the chamber nearly as well as the second time I fire that piece of brass. Specifically in factory barrels with looser chambers where there's a lot of growing for the brass to do.

When I set up my dies for my new .223 I just set the die to zero shoulder bump for the first sizing and fired it again with a warm load and saw the shoulder moved out another .003. After that firing all my brass has uniform distance measured from the shoulder with the Hornady shoulder headspace gauge (to .001"). Then I set the die to bump .002" and I'll leave it that way forever.

So, I personally, would just set my headspace with a go-gauge and not use a fired case. Even though I know that can work, I'm still going to end up with my cases sized perfectly to the chamber and I know that all factory cases will work.

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[joeb33050]

There is a third way, go/nogo, fls case, and the third way, case/s fl sized and measured with the RCBS Precision Mic. The Mic measures case, cartridge case, headspace. Results of fl sizing with different dies and cases are very informative. I have Precision Mics in 223 and 308, and work at getting headspace set so cases fl sized in MY dies just fit. I've changed barrels on Savage 10 and 12 rifles maybe ?75 times, never a problem.
joe b.