I need help from the 9.3x62 reloaders out there

[Gtscotty]

Ok, I'll get right to the problem. I have been reloading 9.3x62 for my Ruger Hawkeye African in PRVI cases using RCBS dies. The PRVI cases seem to be made to the correct 9.3 spec (e.g. slightly larger at the case head and shoulder than 30-06), but whenever I size a PRVI case with the RBCS dies, the dies squeeze the head area of the case down as if the cases were made too wide.

I finally came to the conclusion that perhaps RCBS made its dies to fit a necked up 30-06 case instead of an actual 9.3x62 case. But just to be sure that the PRVI cases weren't at fault, I bought some Hornady 9.3x62 cases and Bingo: the press stroke through the sizing die was much easier and smoother, and the bottom of the cases were not squished (for lack of a better word).

I thought I had solved my problem until I actually went to go shoot the Hornady loads. Probably every other round required two firing pin strikes to fire, and about half of the primers looked very flat. I think both of these problems might be attributable to a head space problem, but I had resized these Hornady cases using the same die settings as I had for the PRVI cases (which had no misfires). Additionally, the Hornady cases look like they have bulged out to the case wall directly above the web (the PRVI cases to not show nearly as much bulging).

So now I'm stuck pondering the following questions:

Are my RCBS dies just made to 30-06 case head specs, or are they actually undersized to the point of being defective?

If my dies are normal, is there another brand of dies that sizes 9.3x62 brass to the correct, original dimensions?

Is the chamber in my rifle oversized?

or, is all of this a head space problem. I set the head space for this rifle the same way I have my others, by smoking the shoulder of a fired case and adjusting until the die just touches the shoulder.

So have any of you 9.3x62 reloaders out there run into any of these problems or similar issues? Thanks for any help you can give!

 

[Jimro]

I reload 9.3x62 with RCBS dies and while I haven't noticed the problem with those dies I have noticed the problem using 6.5x55 dies, too much squeeze on American made brass down on the body of the brass. This undersizes once fired brass and leads folks to say that American 6.5x55 brass is weak and will have case head separation after a few firings (which it can, so I ordered a neck sizer die for 6.5).

I would contact RCBS to see if they won't open up your dies to spec.

Jimro

 

[Gtscotty]

Jimro, Thanks for the response, I'm glad to hear I'm not the only one who has run into this kind of thing.

Out of curriosity, what brands of 9.3x62 cases have you run through your RCBS dies? I am planning on calling RCBS today to see what they can do about opening up my dies a little, also I went ahead and bought a neck sizer.

Do you neck size 9.3? If so, has neck sizing caused any feeding problems in your rifle? I'm kind of thinking neck sizing and going back to the PRVI brass might be the best way to solve my problem.

 

[LouieLouie]

I just received my PRVI brass & RCBS dies today, have experienced the same swaging of the web (doesn't happen to 30-06 brass) and am composing an email to RCBS right now.
I even tried raising the die .020" but I'm gonna raise it up higher just so I can clean the necks w/o touching the body of the case. I've never experienced this before and it's gonna make shooting my new Savage a bit difficult

 

[Jimro]

Gtscotty,

I have PRVI brass, but mostly so far I've just necked up 30-06 to plink with. There is a lot of 30-06 out there (range scrap, etc) so I live with it.

Jimro

 

[LouieLouie]

FWIW, the Prvi brass is right about .474" above the extractor groove while several samples of 30-06 is .471"
With just the expander ball thru the neck to clean it up, a used primer, an otherwise new case has a water capacity of 74.1 gr so I would expect a fired case to be a bit bigger.

 

[Gtscotty]

Jimro,

When using 30-06 brass, are you getting bulging right in front of the case web? I am, and from the look of my fired Hornady cases, it seems obvious that my chamber is larger in diameter than the 30-06 based cases.

Here are a few measurements of some of my brass just ahead of the web (really at the edge of the web).

PRVI (Fired): .475 in
PRVI (Unfired) : .473
Hornady 9.3 (Fired): .4755
Hornady 9.3 (Unfired): .4665
Remington 30-06 (Fired): .468
Winchester 30-06 (Unfired): .463

I just threw the 30-06 measurements in for comparison, the 30-06 was fired out of a Tikka, and I didn't have any un-fired Remington cases so I had to sub in some Winchester cases.

To me it looks a lot like Hornady's brass is 30-06 based, and perhaps a bit too small for my chamber.

LouieLouie,

I'm sorry to hear you're having the same problems, I guess it is not an isolated incident. I actually called RCBS today, the guy in customer service told me that if the die (or a sized case) measured between .467 and .471, just ahead of the extractor groove, the die was in spec. My die measured .469, so I guess that pretty well meets RCBS's requirements...

I've been trying to find an official diagram of the 9.3x62 with dimensions, so I can see what the honest to god specs are, but thus far I haven't been able to find one.

Up until now, I have been using a lee case holder with my RCBS dies. Thinking that this might be contributing to the problem, I went out and got the appropriate RCBS case holder (#3). I've only sized 5 cases with the RCBS case holder, but I think they look a little better.... maybe.... at any rate there is still some swaging of the web.

I think I'm just going to keep using the PRVI cases, full length size them the first time, and then just neck size as long as they are chambering ok. I would still be very interested in hearing what RCBS has to say about your dies if you get a response.

BTW, Grafs sells PRVI 285 gr bullets for cheap, like $29/100. I've been loading these over a decent charge of Ramshot Big Game, I think this load will be a winner when I get things worked out.

Thanks for the responses!

 

[Jimro]

Gtscotty,

I don't have those measurements handy, but your numbers reflect my experience with 6.5x55 which I do have handy. The 6.5x55 and 9.3x62 use the same cartridge head and web dimensions, just slightly larger than 30-06 as you know.

And I had to go to neck sizing in 6.5x55 to keep from overworking the body of my brass. In a small ring Mauser I don't want a brittle body failing when I pull the trigger.

With an m98 (which my 9.3x62 is built on) I don't worry about brass failure. When I was younger and less intelligent I accidently left a 30-06 chamber 40 thousandths too long and it resulted in case failure for the SIX rounds I ran through it. God watches over young boys and fools (he must because he sure made enough of us...) I can't remember where I put those brass, but the web stretched, cracked, and broke off on most of them.

Jimro

 

[LouieLouie]

This link is the the dimensions of the chamber reamer from 4-D Products and as you can see it is .4763" above the extractor groove. Definitely would have a bulge in 30-06/35 Whelen brass.

If that is RCBS' "final answer" then I'll contact Redding to see what base diameter they consider 'in spec'. I've only run 2 cases thru the RCBS dies so perhaps Grafs will exchange them.

 

[LouieLouie]

From Redding:

Louie,

Our 9.3 x 62 dies are designed & built around the SAAMI & CIP specs. We try to resize cases just enough to get the cases back into a minimum spec chamber, and not much extra.

Maximum cartridge diameter at the base ( P1) converts to .4764. Your new PRVI cases, at .474, are within spec.

Generally, you do not need to resize cases for the first firing. Only run them over the expander button to ensure the necks are round. Check the case overall length, check that they chamber, load them up & shoot.

You should measure a fired case at the base and compare to the minimum chamber spec of .4776 (+.002 -.000). If your fired cases are within this spec, our dies will resize the cases just enough to it into the chamber again.

I have attached the CIP data sheet for your convenience.

Look at that die you own for a sharp edge around the mouth of the die. Maybe it just needs to have a smooth radius polished around the opening. The other manufacturer shoulde be willing to with that die.

We will be happy to measure fired cases before you try one of our dies. Just send in 3-5 fired cases, exactly as they come out of your rifle. Be sure to include your name, return address, daytime phone and a printed copy of this email thread if you mail cases to us.

Dave

I was not able to submit the CIP drawing but it sounds like I want Redding dies...

 

[LouieLouie]

Now that I've had a chance to actually shoot my new gun, a moderate load expanded the case heads to about 0.476 with a case capacity of 75.6 gr H2O.
I got an email from RCBS saying that I could send them 5 samples of fired cases with my dies - to help them make a better product I think I will take them up on it.

Off topic: WOWSERS! Never shot this big of a "medium" bore before! Using 51.8gr of A2520 under the 285gr Prvi w/CCI 200 the muzzle flash & blast was impressive - even though the bullets weren't weight sorted it was still cutting clover-leafs @ 50yds once I got the hang of it.

 

[Gtscotty]

Well it sounds like Redding is on top of things, I wonder what RCBS is planning on doing with your fired cases? Did they offer to alter your dies?

I've never tried A2520, what kind of velocities are you seeing? I have tried RL15, and didn't really get where I was wanting to go velocity wise before I started seeing pressure signs. I have recently switched to Ramshot Big Game, and the old 9.3 really shines with that powder.

I think I've settled on 63 - 63.5 gr of Big game under a 285gr PRVI, with WLR primers. This load gives me about 2440 fps which is more or less what I was looking for. I did work all the way up to 64.5 gr (using the realguns.com load data) and was seeing right at 2500 fps, but I decided I didn't need quite that much heat and backed it down some.

Before getting the 9.3, my full power rifle shooting consisted mainly of 30-06 and 270 WSM with 300 mags sprinkled in here and there. While the 9.3x62 is not punishing, with full power loads in a relatively light rifle, recoil is fairly stiff. Tossing those 286 gr bullets at 2450 fps will certainly wake you up!

After I get my 285 gr loads refined, I'd like to work up a load for the 250 gr Accubonds. I've seen a load using 60.5 gr of Varget that's supposedly in the 2600 - 2650 range, I may give that a go.

 

[918v]

What you can do is get another RCBS sizer snd lap it using s new PP case. This will increase the diameter to your liking.

 

[LouieLouie]

Yes, RCBS has offered their services in modifying my sizing die - I've packed 5 new unsized cases and 5 once-fired cases to send to them with the dies. I'll probably send some cases & boolits to LEE to get a collet neck-sizing die made since that's my preferred method - would anybody be interested in a 'group buy'? If so, I'll ask about quantities required for a price break, etc.

When it comes to powders, A2520 being a single-based spherical produces more flash & blast (especially in the 20" barrels) than dbl-based extruded powders, IMHO. Now that I have more data to input to QuickLoad, Accurate 4064 & 2495 are looking really good for top loads with IMR-3031 being an all-arounder. I called Hodgdon about downloading with H4895 - 60% of listed max.load is what can be done when needing a 'plinking' load

 

[LouieLouie]

I just got my dies back from RCBS after having roughly .002" polished from the interior - at no cost to me. Now, the body of new brass barely shows any contact with the dies above the web and once-fired brass doesn't look like it has a belt swaged into it.
Thank you RCBS.