7-08 project notes

[Intheshop]

Working 7 days a week has advantages and not.The "not" part means less time as the student of CB rifle loading/shooting.But hey,guvment'n work is still a time honored system so...two 7-08 items were produced this week.


Made an "M" die insert for an existing die body.The best part being,once past it working perfectly was....I spent a few minutes on our old drafting machine and drew the print.Instead of the usual,on the fly method.The print was on a pce of our shop note pad,which was then held on lathe with a magnet.A process that will be used again!.....3/8" drill rod,zip,boom,bam....turning on biz end done.Spin it end/end and thread 10/32.Use the parent stem from die as a thread gage....done.

Next up,bullet sizing die;

Where the drafting machine lets off....the practical side of producing H&I die,picks up.Meaning,yes you can buy one cheaper than can be produced on a onsey twosey .BUT....the only thing that benefits is the CC co. and possibly UPS?It's not about the money.It's about the "doing" part that gives serious insights to how these little buggers are made.

Drill,ream,hone,polish.The leade in on the female has some real potential for experiment.How much,and angle depends on several key factors.


The "top" of the male part;I just dup'd a factory pce.Which is the place to start but,feel very strongly that we're leaving a good bit on the table here.Meaning,very slight changes to the top of this post can change how the GC is "finished" once all is said/done.BW

 

[quicksylver]

Interesting you should mention the top of the male part of the H&I die..

I revisited all of my H&I dies recently...all Lyman..what I found curious was that a couple had concave tops..very slight but concave non the less...?

If memory serves me right I believe they were on the lager sizes....like .452...maybe a compromise to bevel base bullets????

 

[Pistolero]

Many of them are concave IME, I think they are designed to deal with the common little
sprue cutoff bump on cast bullets, tends to seal better against the base and avoid the squirt
of lube under the base as the joint passes the lube fill hole in the die.

Bill

 

[Ian]

I tend to agree with Bill on this one. Also the cup probably helps keep gas checks from flexing in the un-crimped direction when hitting the bottom stop by supporting them only on the outermost edge. What's even better is the Buckshot design which had a hole drilled through the length of the ejector ("I" part). This would bleed off air and that little bit of residual lube that always accumulates on the bases. I think Buckshot cupped his ejectors, too.

 

[Intheshop]

As always,there's many ways to skin cats.Meaning,I'm gonna try making different "I" ejectors (thanks Ian).They're stupid easy/fast to make.

In the past 40 years of H&I use,I always just figured they were cupped as a way of sealing off the H holes...as the major,the minor being it gives a slight cavity for any built up lube.

Changing lanes in discussion;there has been a holdup on the RCBS 145 mould,it ain't here.So have been using the Lee 130(not soupcan).....subsequently,abusing these bullets and the Lyman 450 to a certain degree,with the ho-made H&I.I Don't like this mould,mainly cause its a RN....but also,I just like bore riders.

So,am NOT gonna waste shop time making a top punch for the Lee,saving that effort for the RCBS.So,have been playing with the I stem/gc seating pressure and creating a flat meplat during this mild abuse of equipment.

Forget the lube right now...and the alloy for that matter.

Concentrated GC seating,with just the right amt of pull/pressure on the 450 presents a measurable meplat,flat top punch.You can immediately tell how consistent the pressure was visually.Don't even need to measure the flat,it's that obvious.

Now back to I stem's top profile;

If it's obvious that there's tight consistency by looking at meplat....in my pea brain the results also show on GC seating consistency.I swear,it didn't take 10 minutes of dinking around with it and boatail visions or synapses' starting popping off in the grey matter.

We have pnuematics,hydraulics,presses out the wazoo in the shop.So yes,probably shouldn't be abusing the 450's,whatever.The SPS stock has been bedded,brrl channel milled out to float,and is in "paint" ( finish dept)...so can't shoot it.It's interesting,the Rem chamber is a few "tenths"(.0001) tighter than the Shaw,for what that's worth.

 

[Intheshop]

Stainless SPS 7-08 is out of purgatory....errr,I mean "paint".A contractor bud stopped by this a.m. while I was mixing black lacquer for spider webbing.He knows enough about guns,had never seen anything like shooting the "snot".Handed him the spray gun and a pce of drywall.Showed him how far to stand back,he had it down pat inside of 15 seconds.I shot the stock,while we talked.

But,it's done....it's the new EDC rifle.1-4 Luepy shotgun scope was a freeby.Beautiful rig.

 

[Intheshop]

Next up....stupid fast "chamber length gage".Actually,or specifically.....length of neck part of chamber.Write it down on that particular rifle's load notes for trim to length.

Pretty easy/fast lathe work;make a shouldered plug that fits inside YOUR case neck.Sliding,snug fit,which will be the minor diameter.The shoulder(major D.) is turned to match the case's O.D.

In use,present the case gently into your chamber,the length or,trim to length(max) will be miked from the oal of this gage.Trim a cpl .001's off your cases....keep notes.

There's other ways to do this if you don't have a lathe.It involves cutting a collar off a donor case,and acts as a sliding ring gage of sorts on that donor case with bullet seated.Dremel the ring off,debur.

 

[Ian]

Another way is cast the chamber and measure it.

 

[Intheshop]

I'm curious Ian,how do you measure OAL with a chamber cast?Do you measure off the neck/shoulder datum?On the gage above it's painlessly easy because you have a true base to trim length.

Considering,I have a lump of cerosafe;Even on chamber neck measures,we just use small hole gages....and don't even do that much anymore.Preferring to just mike case neck,as fired conditions.

And take all this from a guy that doesn't even weigh bullets.I will say.....lube sizing/ GC "seating" pressures when using the cheapy Lee 135 RN.....with a flat,top punch...is so dang accurate,trying to measure the resultant meplat is wasted time.Just sayin....size/bump/GC a handful of bullets,line'm up and a guy would have to be major vision impaired to NOT see which ones took more pressure.

Took about 30 seconds this a.m. to mentally design a direct reading PSI gauge for measured bump pressure.That was easy.It took a cpl more minutes to come up with a quasi articulated ,LBT hardness tester "style" mechanical metric assembly...doh.So,went into the nursery(loading rm) and cranked out a few 7's.I swear....creating the bumped meplat is so easy/accurate/consistent.

 

[Intheshop]

Oh yeah,the SPS 7-08 stock colour is.....wait for it.....

Oak tree lichen,with black spider web.I'd have to confab with the oldest(degreed up pro $$$ artist) on "why"....but my hillbilly pea brain calls it camelian effect.The shade of tan/yellow/Martha Stewart green changes almost as good as that ghetto chromeulsion paint used on cars.Meaning,it changes tone depending on the light and background colours.....

It is stupid cool.The black,is a "qualifier".

Wish I knew how to post pics,took some suitable for framing pics Thursday evening up against some slimy green moss covered rocks.I'm using Easton green anodized arrows,lashed together as shooting sticks.Got clear surgical hose on the top 5" or so.

 

[Ian]

Calipers or "verynears". Make a pound cast and measure from the face of the case head to the end of the chamber, easy peasy. If you're using sulfur or Cerrosafe, I guess it wouldn't work like that.

 

[Intheshop]

Made the little gage tool,now I know exactly what the max O.A.L. is,of a case.Took 1/2 hr,or so to make,a few minutes to use,threw it in the toolbx in loading rm.

What's interesting....or not?Is making the above gage is "about" halfway to making a spud or mandrel for neck turning brass on a lathe.I already have a hand turner that only gets used once in awhile.Think big fat CB's in "tight",saami chambers.It happens,ymmv.

Big shout out to Earnie Paull gunsmithing.His "hunter" weight replacement X-pro Remington trigger spring took the 7-08 factory adjustable......"I'm turning this socket cap set screw in the trigger face,and it's 4# screwed all the way out"*.......

To EXACTLY what I want in a hunter trigger,3 1/4#.....,.010" of overtravel,.020" sear engagement.It'll go down to about 2 1/2#....or so.Soldering iron gets the "chit" off the factory weight of pull screw(replacement spring lives under).

Interesting point about taking the bedded action out of stock for trigger work was,when reinstalled,scope zero was spot on.Still puts the dry mopped(brrl) 1st shot a 1/2" high.

*note;the little set screw on X-pro trigger face screwed all the way in is 5 1/2# with factory spring.