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Bought a new X-Caliper barrel for my 22-250. It's an 8 twist so I plan to load as heavy as I can, so brass life may be an issue.
I'd like to headspace it using new Lapua brass and a couple of layers of scotch tape to get a good tight headspace and try to limit case expansion/growth.
My question is; how tight is tight enough?
Thanks for any advice or experience you can lend.
Well.... FWIW
As long as you don't over-pressure things, brass life should be completely normal. "signs" of excessive pressure, mean VERY excessive pressure, that's why many think brass life is short in certain things. Typically Lapua tests cases to 130% of cartridge pressure. So when you "notice signs" you can bet you are near 130% of operating pressure.
I've never understood the tape part, personally. What that does is allows the gauge to appear longer, than it otherwise is, meaning that you have more headspace, not less.
^ Yes ^ JMNSHO...as long as the case will chamber, the "best" head space, is "zero" head space.
Now, that being said, if you find the longest piece of Lapua brass you have (to the datum line), and set the head space to it, a go gauge would probably not chamber. If you want to get the chamber closer to the go gauge, you could then add tape, but I have no idea how many layers it would take to get you where you want to be. I only shoot My reloads, so I don't mess with the tape.
For Me, next step is to fire a reload in that chamber. Then & only then is that case ready for "serious" reload. :-) again JMO
My LGS says that clear packing tape is 0.002". So if you set on the "go" ga and then add tape and use it as a "no go" you will have 0.002. Then remove on confirm your "go" ga again.
The reason I'm asking is that I am currently shooting this Factory chambered model 12FV and am experiencing case growth of about .002". I bump the shoulder in a FL die, and note that the neck grows about .006". So I trim the necks whenever case length goes over SAMMI spec of 1.912".
This sounds pretty typical to me, from what I read, but I'm fairly new at the whole bump and trim process. My 223 is neck sized only and I never have to bump the shoulder to get good fit.
So in setting up this new barrel, I'm hoping to lessen case growth and lengthen the life of my expensive brass, if that is possible, by setting a tight headspace.
Do I really need a go, no-go gage set, or will a new unfired Lapua case work as well, presuming I do as FW suggests and pick the longest one, and then use tape as Strut suggests as the no-go gage?
Please note; it is my understanding is that this new barrel has a SAMMI spec chamber.
A single go gauge and tape will suffice. Problem with headspacing on a case is the shoulder area is soft in compression compared to a gauge. It takes a lot of 'feel' to get it as consistent as a true tool steel go gauge. Unless you have case length gauging its hard to verify the case you're using is close to correct. In most cases if you only have one rifle and reloading setup for this caliber you'll be OK, but if you have two or more and want to size cases to fit both at the same die settings you can chase your tail trying to headspace multiple rifles via the case method.
You're better off headspacing slightly long than short, because your resizing dies ain't gonna size for a short chamber, and the extra compression using the case headspace method can lead to a short chamber. I think the tape on a case was a wise suggestion.
I'm also personally a fan of clamping the action tight in an action wrench to lock the barrel to action together once headspace has been established before nut tighten.
It really depends on your objective.Quote:
Originally Posted by darkker
I think a lot of it comes from the military where brass life is a laugh, all they want it to do is work.
Ergo, good chamber clearance, plenty of headspace.
Brits and the 303 are famous for it, 3 reloads and its a goner no matter what you do.
From personal experience, the Model of 1917s out of the box almost fail a field reject gauge.
What you are doing with the tape on the go gauge is making it act like a no go gauge (or someplace in between depending on how thick a piece of tape you use or layers)
Hunting you also do not want tight, not as much as military but not cramp in tight.
Target shooting, whole different story. I am inclined to tight but not where there is pressure on the bolt closing. That's just me, YRMV, I am just shooting targets these days
Thanks, guys. There's some sage advise in your responses, and I think I'm going to use the best technique I can muster, and borrow or buy a headspace gage. I plan to shoot long distance and as accurate as I can, so I'm thinking its best to NOT leave room for doubt by short cutting the assembly.
For the record, I'm not the kind of guy start at max load and go up from there. I pay attention to signs of overpressure, and I now have a good chronograph so no more guessing about velocity/pressure.
Darkker, I'm heeding your advise and going by the manuals listed velocities.
Once I've got this figured out and shooting well, I expect Savage will have another sale and it'll be time to buy another 12FV for a 6mmBR build. Down the rabbit hole I go!
I have a different school of thought here and it has worked extremely well for me in the past. FWIW in my rifles I only shoot handloads.
If I am adjusting a factory installed barrel for minimum headspace, what I like to do is take 2 or 3 cases that were fired in the barrel and run them through my FL die or body die (depending on situation), then set my headspace to that sized brass. Add a piece of scotch tape to get the no-go. From there on out I neck size only until the brass get to where it won't chamber easily. Then I just run it back through the FL die at that time and start the process over. Doing it this way I have nearly eliminated trimming in many chamberings and I feel I am getting the best brass to chamber alignment situation also.
If I am doing a new uninstalled barrel then I like to install as normal with gauges, if no gauges can be procured then I will do as someone stated above and use the longest piece of brass I have. Then repeat process I just described above.
FWIW I prefer to use the Lee Collet Dies for neck sizing wherever possible. I have had great luck with these on Standard and the Ackley Versions of all my chamberings.
^ I like the way You roll "boots" :-) ^
The new go-gage arrive today from Midway. I had installed the new 22-250 barrel a few days ago and had used a new Lapua case to set headspace. Bolt closed on new case, would not close on new case with one layer of Scotch tape (.002 thick). Ejector and extractor are removed from bolt head.
Today I chambered the Go gage and the bolt would not close on it. If I have learned anything, this means I have adjusted the headspace to below SAMMI specs.
Presuming I am going to shoot only hand loads, and can adjust my FL die to bump the shoulder to fit MY chamber, is the way to limit case growth?
Thanks for any help.
New virgin brass typically runs a few thousandths less head clearance than minimum chamber headspace. Since you're only reloading its not a big deal resizing the brass to fit the chamber provided your die and shellholder will allow it. Now, if you have to shorten the die and or use a holder with less deck height you may want to use the gauge to reset the HS and fire the brass as-is. Its six of one or a half dozen of the other depending which way you want to go.Quote:
Originally Posted by Texas10
Bill
Back to brass life. Now that you have head spaced your rifle are your dies set up correctly?
Quote:
Originally Posted by Robinhood
I'm not sure what is correct, which is why I am asking for your experience. I do know that I had to bump the shoulder every time I reloaded to get the round to chamber in the previous barrel. I also had to trim the necks every two cycles. And I foresee that this is going to eventually cause case separation if I don't toss the case beforehand. The question is how many cycles, and what can i do to reduce case stretch?
That is the essence of what I am inquiring here. In setting up this new barrel, what can I do to reduce case stretch or elongation during each cycle?
Thanks for any help!
This is the problem I was speaking of when trying to headspace with a case. The brass case is easily compressed a few thou, especially with shallow shoulder angle cases, the solid steel gauge is not. Quite frequently when headspacing on a case the chamber ends up shorter than the die can resize brass to.
Quote:
Originally Posted by Texas10
22-250 is a barrel and case eater. You'll be tempted to increase speeds (its an addiction) which will shorten case life even further. But its fun while it lasts. Expect 2-3 reloads on Remmy brass, double that for better brass. Get a LR primer pocket 'swage gauge' from Sinclair- every reloader needs one of these! Throw brass away when the primer pocket gets loose, you get a radial line about .200" up from the rim (case head separation parting line), or a split neck.
Set up your dies so the resized case won't chamber with tape on the head, excessive headspace on multiple firings is where the case head separation comes into play.
Quote:
Originally Posted by Texas10
[QUOTE=Scott Evans; Set up your dies so the resized case won't chamber with tape on the head, excessive headspace on multiple firings is where the case head separation comes into play.[/QUOTE]
Yep, did that. Won't re-chamber after firing, except with effort. Bump the shoulder .0015 to .002 and chambers easily. But the neck grows .006 every resize.
Nature of shallow shoulder angle, tapered body, high pressure cartridges. They all do this, the brass flows. Going AI reduces this.Quote:
Originally Posted by Texas10
Case head separation is caused by the case being undersized in the head space dimension, or from base to shoulder. When the case base to shoulder dimension is shorter than the chambers bolt face to shoulder dimension the case grows just above the web area.
Brass flow, where the neck gets longer does not cause case head separation. as Scott said sharper neck angles reduce or practically eliminate the flow.
just my opinion
Well I see 2 issues here original barrel installation headspace
and adjusting the sizing die for minimal headspace on fired brass.
I am a firm believer in headspacing with a go/no go set of headspace gauges while installing your barrel
Then after fireforming your brass setting up your sizing die for a bolt gun at a 0.001 to 0.0015 shoulder bump.
Well, I set the headspace with the gage, but set it a bit tight. Bolt closes about half way on the gage and get tight. It closes easily on the unfired, Lapua case, and closes with a little effort on the case with one layer of scotch tape. So I am just under SAMMI spec by about half a thou, maybe a full thousandth.
If I read it correctly (m12lrs) , it comes down to FL sizing die adjustment, and I think I've got that down pretty good now. Thanks for the responses, guys.
Gonna take it out Thursday and see how it shoots the 80 grain A-Max.
+1 Yes indeed.Quote:
Originally Posted by Scott Evans
I would add, although may not apply to this particular loader. Federal is well known to have dangerously soft case heads. They like very soft brass for case obturation and accuracy. While that does work, it is at the price of very short case life.Quote:
Originally Posted by Robinhood
^ Does this mean that a fire formed case, neck sized and reloaded, is a good thing? ^
you can neck size only until the cartridge will not chamber. That depends a lot on the cartridge and how hot you load it. Then you will have to at least bump the shoulder if not full length resize.Quote:
Originally Posted by FW Conch
I agree with M12lrs above. But in the case of extra soft Federal heads; yes.Quote:
Originally Posted by FW Conch
I'm not saying that they ALL are bad/dangerous/etc, but have found many more than I care for. We've had them seperate while testing with the Pressure Trace too.
Personally I took a hammer to any remaining that I found. Assuming a decent rifle and not over-loaded, head-seperations aren't typically a terrible event. So use them, don't, whatever makes your day. Just be aware that a seperation with one isn't inherently from pressure.
Obturation is the subject for another thread. Don't want to hijack this one.
I avoid Federal brass also.
I measure the base to datm on brass before firing and them after firing to establish a baseline before doing anything, well unless I use a gage which I measure also. I quit using an expander ball in resizing dies years ago, all they do is stretch necks and make them crooked no matter how well the ball and inside of the neck are lubed. Before headspacing I also try a piece of fired in the gun brass to see what the dies are capable of.
Range report:
I shot the new barrel using a load work up with 80 gr. A-Max and H-4350, and I have to say that setting the headspace close was a good move. All of the shot brass measured exactly what it did before shooting.
I was able to re-chamber the ejected brass easily so this may just do the trick and extend my brass life.
The 4350 shot very well, right up to max book load. No primer, or other signs of excessive pressure, and although the Magnetospeed said I was about 100 fps over book velocity, my barrel is also 4 inches longer than book.
Interestingly, I took my bore scope camera with me and performed a before and after view of the chamber/throat at the first shot. It's amazing how much the first bullet knocks down the lands in the leade. I noticed this on my new Criterion barrel too. Big changes occur during that first shot.
^ That's what I'm talkin about! ^
Thanks, for me I just found it was a lot less work to set the barrel once to match the dies rather than try to set the dies to the barrel. If I had a Remmy then by all means setting the dies to the barrel makes complete sense to me because of the inability to adjust headspace, but with Savage its adjustable so might as well utilize it. I know that doing it the way I suggested is not everyone's preference, but for me its simpler, makes the handloading process faster and accuracy seems to be comparable if not identical in my experience.Quote:
Originally Posted by FW Conch
OP, glad to hear your results thus far.
Just remember that you also don't have a SAAMI minimum spec: Bore, Groove, Chamber, as was used in the universal receiver used to determine pressure either. Perhaps the barrel length would add something, but don't expect a miracle from it.Quote:
Originally Posted by Texas10
If you are happy, fantastic!! Just remember "signs" aren't accurate, but your chronograph is.
Wouldn't get too concerned with 100 fps difference, Magnetospeed is like 4" from end of barrel at first timer, chronos used in lab load dev are going to be further away and I have no clue if they use a conversion to MV or what, I suppose its all spelled out in the SAAMI spec, anybody know? You can easily lose 100-150 fps from actual muzzle to 6 to 10 ft away.
I think it's everything, but at least on pistols SAAMI uses 15' from the muzzle.
Unless you are shooting a pie plate, there isn't any match bullet fired from a 22-250 that is going to lose 100-150 fps in 10 feet. Don't think any bullet anywhere would lose that much velocity, but don't have my ballistic calc on this phone.