Another disappointment at the Range.

[Sure Shot Mc Gee]

reloader28 & oldmanFCSA I think I see your point. By increasing the dies gap between it and its shell holder. The shell doesn't grow as much during its firing. Thus eliminating some of my shells (work hardening) near its base. What do you guys suggest is a reasonable starting gap measurement? I've read what GeauxTide suggested which is a great suggestion. (pocket change) But I'm fortunate to have an old set of tappet feeler gauges handy. Which I think would work a bit better for me (more of a precise adjustment in either direction can be had in there using)


mrawesome22: looks like your ahead of the curve this time but not by much. lol

 

[oldmanFCSA]

On a fired pc of brass, set shoulder back 0.002"max to eliminate case head separation.
Your die setup is forcing shoulder back too far.
What happens:
Firing pin pushes case forward in chamber.
Light primer strike causes slow ignition.
Case expands at shoulder and neck grabbing case wall against chamber wall.
Unsupported case head stretches back against bolt face.
Weakest portion of case is stretched just above case head.
Repeated practice willseparate case head as you have descibed.

Also, primers may be severely flattened with moderate loads by to short a case.

 

[oldmanFCSA]

SB = Small Base dies

Small Base dies are sometimes used for reloading for lever-action or semi-auto rifles to assist in chambering a round.
These dies only squeeze the lower 1/4 of case smaller in diameter to ease chambering.
Improper die setup with ANY die will cause case head separation, do not blame S.B. Dies.
Screwing a die down to shellholder is WRONG - I don't care what reloading manual says - do it right for YOUR RIFLE - not for the masses.

 

[tobnpr]

I've only been reloading for three years, but have done about 8,000 large cal centerfire rounds on my LNL over that time...

Never gotten less than a dozen firings (bolt guns) from my brass, and usually I set them aside "just because", not because they've failed. When they do, it's a cracked neck...never had a case separation.

I FL size every case, trim only when necessary (which is usually only once during the life of the brass), and just set the press to cam over hard on the die. This most always results in .002 shoulder bump from the fireformed cases.

Every reloader should have a headspace gauge to check shoulder bump...

 

[Sure Shot Mc Gee]

I believe this is what you fellows suggested I purchase.

L.E. Wilson Case Length Headspace Gage 300 Savage

My question now: would I be better off buying this Wilson HS/G? or a different manufactures model? (for ease of using)

P.Script: I do have a good stainless caliper here for measuring accurately.

 

[HiBC]

That bushing gage will be quite useful.Good investment!!
You drop in the case,like a chamber.It has a step ground in the top,a few thousandths lower than the top surface of the bushing.The step represents the low limit,the shortest your ammo should be to be SAAMI length.Dont resize your brass to be shorter than that.The top surface of the bushing represents the longest your brass should be.If the brass is below the top,your rifle should close up and lock,if it does not,shorter is not the answer,something else is wrong.

On the other end,if the neck protrudes,trim your brass.

Now,you can use your calipers with this bushing as a fine tune.So long as the neck does not protrude and confuse the results,measure over the cartridge case and the bushing assembled.You may have to do some testing with sized brass to find the longest(least sized) brass that will chamber easily,write that length in your die box.You might go .001 or .002 shorter for reliability.

Now you have the means to load to a known length that will chamber reliably,yet works the brass as little as possible.That will give you as good of brass life as you can get.

Still do the paper clip trick routinely.When you are finding stretch rings ,discard the lot.

Good luck

 

[wncchester]

You're setting the shoulders back too far and probably loading a bit hot for good case life. Excess shoulder set back leads to unneeded case stretching. The 99 locks at the rear and tends to spring more than front locked rigs so that adds to the case stretch on each firing.

By reducing the amount of case stretch we produce we can greatly extend case life. All a Wilson type 'drop in' case gage will tell you is if your ammo falls within the SAAMI minimum and max lengths and is helpful if you want to swap your reloads around other rifles but it won't tell you a thing about how well your ammo actually fits your specific riflle.

Simplistic die set up by the numbers will make ammo that will chamber and fire but it can't be very precise. Setting up a sizer properly requires something that can give us exact information, something like Hornady's easy to use cartridge "headspace" tools that mount on the jaws of a precision caliper are good. Use that to find where fired shoulders are and then resize to restore the shoulders back to where they were, or just a tiny tad shorter. Doing that will greatly reduce the incidence of head seprations in any rifle. My cases die due to neck or body splits, I've not had a head seperation in almost 50 years of reloading.

 

[HiBC]

wnchester:I agree with most of what you said.Here is where we differ:

In my 30 yr career as a machinist/toolmakerQC/etc I have learned there is more than one way to take a measurement.Some are better than others,but if we are measuring the same thing to the same degree of precision,it does not matter much.

I agree,by itself,the bushing gage only checks hi/lo limit.

I agree,the Hornady/Stony Point caliper attachment will allow a comparative before/after measurement to control how much setback you are making.

The OP said he had calipers and (I think) bought the bushing gage.

Case inserted in the bushing gage,the shoulder is resting on a datum diameter,yes?Just like the Datum bushing on the caliper attachment.If the OP uses his calipers to measure the +/- over the case head and bushing,he is achieving exactly the same measuring process as using the caliper attachments,and it is done with the same calipers,to the same precision.

If anything,IMO,as the over bushing measurement is more direct,no clamping on of attachments and adapters,it is probably more repeatable/accurate.

Once again,I agree with what you are saying,I think I failed to clearly communicate how to measure it with the bushing gage and caliper.

I actually have a small black granite surface plate/comparator stand with a dial indicator I can slide the bushing gage and cartridge case under for a quick inspection.

Its all good!

 

[tobnpr]

I don't get the advantage of the Wilson, caliber specific gauge over the Hornady.

Perhaps if you had concerns about the chamber itself being in spec... but that's not what's being discussed here. You can buy the Hornady set with 5 bushings that will cover near every caliber for the about same price as the Wilson, which covers one...it's a no-brainer for me for the purpose of checking shoulder bump on reloads.

Just like the bullet comparator, it's all about relative measurements- but that's all that we're usually concerned about. Long as you've got the fireformed case, you're all set.

 

[Sure Shot Mc Gee]

As read. Your threads. HiBC-wncchester: It isn't hard to adjust the resizer die for correct shoulder set back. But to do properly one has to have the right tools to do the job. That's what you've both taught me. I've seen both the Wilson drop in Headspace gauge and the Hornady with its assortment of bushings I think? >that clamp onto a caliper. Decisions? decisions? Be assured guys I'm going to buy one or the other pretty darn quick here.

Funny thing about this Headspacing. I have a 270 and 25-06 in bolts. I've set my SB dies the same for them two as I did for the 300. And really run hot, hot charges in them both and have yet had a separation or anything else happenings in either bolt rifles. "Yaw just gotta love them 300 Savages to want to own one." lol_

tobnpr said:you've got the fireformed case, you're all set.

Yep I sure do have a few from the last time I was shooting.

 

[HiBC]

The Hornady setup will work fine.The point is being able to make the measurement and set the dies accordingly.

Somehow I got the idea the OP had ordered the bushing gage.

We are on the same page,its all good.

 

[Sure Shot Mc Gee]

Well decision making time is over with fellows. I ordered a Comparator Set made by Hornady w/ 5 bushings that claims to work on nearly all popular calibers. Seemed liked the Hornady tool was the best bang for the bucks. I sure hope it comes with a good set of instruction. Yup. Old school reloader learning new tricks. Well see. _

 

[tobnpr]

It's very simple...
Each bushing fits a range of calibers.
It's not a matter of being an "exact fit" for any reason, the correct diameter bushing will slide down to a certain point- "x"- on the neck, of your fireformed case, and you measure the length from the base of the case with your caliper.

Run a case through your sizing die, then check it, ideally you'll be about two thou shorter. If you don't get enough, be sure you've set the die about 1/3 turn past contact with the shellplate so that the press cams over hard.

With a tight spec chamber, it can be tough to get enough bump...factory dies are conservative for obvious liability reasons, they're not going to set back the shoulders out of spec.

 

[Sure Shot Mc Gee]

tobnpr. The way you explain how the tool works. It shouldn't be all that hard to master. But for the sake of conversation. I compared a live reloaded round with a brand new un-loaded brass tonight. There was a difference seen in their shoulder heights. But I'm not to sure if the S.B. Resizing die pushed the shoulder down or my Seater die has to much crimp set on it and collapsed it some? Being my brass are all trimmer the same length I hope that Comparator will resolve that mystery for me?

 

[1stmar]

Make sure you check a number of cases, the amount of lube on the cases will cause variation in how much the shoulder is pushed back.