Final headspace

L

Lucky Shooter A

Guest
I've read a lot on here about setting final headspace at the point where a stripped bolt will have a slight drag when closing on a GO gauge.

I'd like to get a slight crush fit on the new cases I'm using but these cases are slightly shorter than the Go gauge.

I'm thinking about reaming for a .002" crush with the new cases-----have hand-picked several for consistency.

Does .002" crush seem to be excessive ?

Will appreciate any comments.

A. Weldy
 
Not if you have a die that will work with that headspace.

A little is a lot when it comes to sizing.
 
Lucky,

I don't know about the "crush" but when I install a new barrel on my Shilen DGV I use a go gage and a no-go gage. The stripped bolt must close completely on the go gage, and close about half-way on the no-go gage. Not sure if this helps, it's just the way I was taught when I bought the rifle from Shilen a few years ago. I do this before tightening the barrel nut, then double check to be sure.

Dennis
 
Lucky Shooter A said:
I've read a lot on here about setting final headspace at the point where a stripped bolt will have a slight drag when closing on a GO gauge.

I'd like to get a slight crush fit on the new cases I'm using but these cases are slightly shorter than the Go gauge.

I'm thinking about reaming for a .002" crush with the new cases-----have hand-picked several for consistency.

Does .002" crush seem to be excessive ?

Will appreciate any comments.

A. Weldy
Click to expand...

Another opinion.......

I believe that THE ONLY WAY to make good cases is via crush fit. A nice TIGHT crush fit. Like HEEL THE BOLT CLOSED tight fit. As to "what's excessive" that's a 'feel' item. I go as tight as I can comfortably close the bolt with the rifle held close to the chest and pointing at the sky......TIGHT. And grease the lugs frequently. This method will yield scrupulously straight, square and easily maintained cases always..... HS needed to effect this varies according to a host of parameters. You'll need to go a lot more than -002 for AI's and low-shoulder-angle cases. Also the radius of the bearing surface plays a part. My reamers are ground with a 3X tighter radius at the N/S junction than are others. But any-road you MUST jam tightly to get good cases.

There are no exceptions to this rule.

I have gages, I use them for reference. My typical 300WSM chamber will be marked "-.006HS" which means six thou under the GO........I haven't chambered a rifle (nor willingly had a rifle chambered by anyone else) to just "close on the GO gage" in 30yrs.

The idea of "hitting the slot between GO and NO-GO" is revolting to me, as is the concept of "binding partway down" as these two items define poor, sloppy tolerances and/or misaligned surfaces.
 
BTW if your die "doesn't work" walk over to the bench grinder and GRIND IT OFF..... the idea of a resizing die ever touching or even being close to the shell holder is equally revolting to me.

But then my requirements are brutally simple. My setup MUST be such that cases can be fired 50+++ times at ridiculous pressure without case growth. And with ZERO 'feel' when dropping the bolt handle.

WHATEVER IT TAKES to accomplish this.

50 perfect firings, no hassle, just load/shoot load/shoot

No variance, no annealing, no heartache of any sort, just SHOOT.

There aren't 25 people on this shooting board who believe this is possible.

But as my buddy Jesse says, "SORRY...... you just cain't argue wit' results"...

I CAN and DO accomplish this with chamberings up to and beyond .338 Lapua pushing 300's at 2800fps........I can go up to 3000fps but my case life drops off some, the cases don't GROW but I start having to cull for loose primer pockets.
 
Thanks to all for replies

Al-----you have a PM.

A. Weldy
 
If you have short

alinwa said:
Another opinion.......

I believe that THE ONLY WAY to make good cases is via crush fit. A nice TIGHT crush fit. Like HEEL THE BOLT CLOSED tight fit. As to "what's excessive" that's a 'feel' item. I go as tight as I can comfortably close the bolt with the rifle held close to the chest and pointing at the sky......TIGHT. And grease the lugs frequently. This method will yield scrupulously straight, square and easily maintained cases always..... HS needed to effect this varies according to a host of parameters. You'll need to go a lot more than -002 for AI's and low-shoulder-angle cases. Also the radius of the bearing surface plays a part. My reamers are ground with a 3X tighter radius at the N/S junction than are others. But any-road you MUST jam tightly to get good cases.

There are no exceptions to this rule.

I have gages, I use them for reference. My typical 300WSM chamber will be marked "-.006HS" which means six thou under the GO........I haven't chambered a rifle (nor willingly had a rifle chambered by anyone else) to just "close on the GO gage" in 30yrs.

The idea of "hitting the slot between GO and NO-GO" is revolting to me, as is the concept of "binding partway down" as these two items define poor, sloppy tolerances and/or misaligned surfaces.
Click to expand...

cases, one way to get the crush fit Al describes is to expand the neck up to the next caliber and then size back and leave a false shoulder that will create the crush. I make my 30 x 44 cases in this way, using a 338 expander and then sizing back to about .010 crush fit. Same for my 30 PPC, made from 7.62x 39 brass.
The system works well.

David
 
David Halblom said:
cases, one way to get the crush fit Al describes is to expand the neck up to the next caliber and then size back and leave a false shoulder that will create the crush. I make my 30 x 44 cases in this way, using a 338 expander and then sizing back to about .010 crush fit. Same for my 30 PPC, made from 7.62x 39 brass.
The system works well.

David
Click to expand...

David is absolutely right, and while this is always just a little harder TO DO than you expect it to be it does work very well. I too have experienced that one needs a lot of crush interference when doing it this way but it is possible via trial and error to get a nice solid crush, especially if one necks up "two calibers" or more. (I say "two calibers" because I tried to use .338 for necking up .325 cases and just couldn't get it to work, ended up making a funky 'spander myownself)

Expect to split a few casenecks mandreling up, and note that this is one instance where I DO NOT advocate blowing the necks up with pistol powder.

Ya' only get's ONE HIT on that brass without re-annealing ;)
 
I use the false shoulder on br cases to make dashers. Turn em to desired thickness, Run a 25 or 26 cal mandrel in and size them in my dasher die thats already set. The bushing sizes it down to the right spot on the neck and that rounded false shoulder crushes down and centers it all up just right. Plenty of info on this just google up dasher false shoulder
 
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