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Justintyler
12-05-2016, 08:49 PM
I've always used a round in the chamber closing the bolt and tightening the barrel till i get slight tension on the bolt . do the factory stamps ever line up as they should on the left side or am i just setting it too tight ? its currently 1/4 turn backed off (stamp about 1 o'clock looking from the action forward) if i turn it til the stamp lines up the bolt will not close. if i loosened the barrel tip the stamp is correct again that would be a full turn loose. I've never had any problems with this way i guess its just a curiosity i have ?

Robinhood
12-05-2016, 08:57 PM
do the factory stamps ever line up as they should on the left side or am i just setting it too tight ?

Nope and Nope. For every complete turn of the barrel the head space moves .050". 1/4th of that is .0125" the range of adjustment from no head space to maximum head space is 1/10th of a turn or about .005.

The stamping on the barrel is random and is contingent on the bolt head and the actions and barrels threads. Why worry about it unless you are trying to fool someone.

redman
12-05-2016, 09:05 PM
I'm pretty brave on working on my own rifles but I wouldn't dare use a brass to headspace. I don't even like using the tape on the go gauge trick. Brass can be quite a ways off til it is formed in a properly headspaced chamber. So to answer your question ....who knows? Who knows if your brass is the exact dimensions to use as a gauge? Something to think about.

Phranque
12-05-2016, 10:34 PM
No offense, dude.... but Jeezy Pete! Is your (or potentially someone else's) safety not worth at least the $30 to buy the right tool for the job????

Justintyler
12-06-2016, 12:12 AM
I guess I should have been more clear. "Round" wasn't the correct term. I use full length sized piece of brass . Which is the method I learned on this forum 15 years ago. Some feel it's safe some don't . I personally have never had any issues doing it this way. I greatly appreciate every criticism and comments I receive on this forum from all members. I've only done 5 builds in those 15 years and have learned lots along the way and still have more to learn I know .

Phranque
12-06-2016, 01:15 AM
I guess I should have been more clear. "Round" wasn't the correct term. I use full length sized piece of brass . .

I know exactly what you meant, and I still meant what I said... Compressing against the shoulder of a soft piece of brass can potentially yield greater errors than a milled piece of steel, plus that piece of brass may not be resized to the perfection that the GO gauge has been milled to. That method may have been "acceptable" 15-20 years ago, and probably does work 999 out of a 1000 times, but with the cost of a proper, quality GO gauge only being $30, why risk it. Again, sorry if I've sounded harsh, but when it comes to working on firearms, I am a firm believer in absolute safety first, which means the correct tools for the job. If you screw something up, you can literally be holding your own life in your hands.... or, forbid, someone else's if they are shooting it.

short round
12-06-2016, 04:49 AM
FYI Roll marks are put on after head-spacing at Savage. If by chance they align up when swapping barrels around, I'd buy a big lottery ticket.

Robinhood
12-06-2016, 07:32 AM
I know exactly what you meant, and I still meant what I said... Compressing against the shoulder of a soft piece of brass can potentially yield greater errors than a milled piece of steel, plus that piece of brass may not be resized to the perfection that the GO gauge has been milled to. That method may have been "acceptable" 15-20 years ago, and probably does work 999 out of a 1000 times, but with the cost of a proper, quality GO gauge only being $30, why risk it. Again, sorry if I've sounded harsh, but when it comes to working on firearms, I am a firm believer in absolute safety first, which means the correct tools for the job. If you screw something up, you can literally be holding your own life in your hands.... or, forbid, someone else's if they are shooting it.

If you are pressing against the shoulder you are doing it wrong anyway. Using brass is not ideal but if you have half a brain you can test and retest your chamber until you are confident it is close. After all, we are Savage smiths.

sleepy
12-06-2016, 08:51 AM
A "full length resized piece of brass" doesn't always mean very much. The instructions for most FL sizing, dies say to run the die down until it touches the shell holder. I bought a 223 FL die set once that when adjusted this way, caused signs of too much headspace in every gun the brass was fired in.
After I bought a Wilson headspace gauge, I saw that resized brass from this die, fell very much too far into the gauge. I returned the die and it's replacement didn't have that problem, but I learned a valuable lesson from that experience.

rosewood
12-07-2016, 04:00 PM
I see the point of using real head space gauges, but if you adjust it with a full length sized case, then test with various cases as well as maybe a factory loaded case and you are getting good results, could that really be that bad? If you have that cartridge in another gun, compare your testing cases in both.

Rosewood

dlsculley
12-20-2016, 06:39 PM
There are many options for headspacing when installing a new barrel. If you want a barrel set to SAMMI spec then you need to use the proper headspace gauge. This simply assures that all factory ammo will fit in that chamber. If you will only be using your handloads, then using a sized case is an acceptable method. You just have to understand that factory ammo may or may not fit your chamber. I know a really good gunsmith that shoots a 6.5x47 Lapua in competition. When he builds a rifle for himself or his wife, he adds a shim to the base of the headspace gauge to make the chamber longer than SAMMI spec. After he has fire-formed his cases, this provides a bit more room for powder vs. the SAMMI spec chamber. He gets a bit more MV this way. None of these methods are "wrong". If you do chamber a in any method that yields a non-SAMMI spec chamber then you should make a note of it and if you ever sell the rifle you should either re-set the headspace to SAMMI spec or mark the barrel as Non-SAMMI spec chamber.

When I built my 6.5x47 Lapua, I used piece of new Lapua brass. I wanted minimal brass expansion for long life. This has worked well for me and the rifle shoots extremely well. When I put my 7 RemMag barrel on, I use a piece of brass to headspace this as well. When I do this, the bolt will not close on a headspace gauge. Using this method, I don't get the bulge near the belt as I used to and the brass lasts longer. After installing the barrel, I cycle all the brass that I plan to use for the rifle to make sure the bolt will close.

The main thing to understand here is that if the chamber is a few thousands shorter or longer than SAMMI spec it is not necessarily wrong, it is just not SAMMI spec. As long as you understand what you are doing and proceed accordingly it is not inherently dangerous to have a non-SAMMI spec chamber as many would have you believe. If that were true, wildcatting rounds would be a terminal endeavor. Use good judgement, proceed with due caution and accept responsibility for what you do.

FWIW,

Dennis

ninner
12-20-2016, 07:15 PM
I always set headspace on factory ammo after removing the firing pin. I have checked my results with headspace gauges and have been spot on. What risk do you feel is involved? Unless your pushing Max pressure reloads there is none.