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DrMLap
06-02-2018, 11:34 PM
I recently purchased a box of .303 Savage ammo from Graf & Sons. These have 150 gr jacketed RN bullets made by Hornady. I fired them in my son-in-law's Savage '98 which I had had thoroughly inspected by my gunsmith before firing anything in it. It shot just fine with no problems except one puzzling anomaly. Every case I ejected had a slightly extruded primer, about .016" to .020". And, oddly enough, the primers do not look flattened, as would be the case with a too powerful load. Indeed, the recoil of the weapon felt nominal. Other than sticking out a little, the fired primers looked normal.

It is my understanding that the headspace on a rimmed cartridge like the .303 Savage is determined by the gap for the rim measured from the face of the bolt. Thus, if the gap is too large or the rim is too thin, I could conceive of primers backing out. The rims on my cartridges measure about .058". The data I found says it should be .063". That doesn't seem to be sufficient to cause my problem. I have nothing with which I can measure the actual headspace of the rifle. I can only assume my gunsmith did that.

And in case someone should ask, yes, the Savage is chambered for .303 Savage and which is stamped on the gun.

So what could be causing my primers to extrude? Do I need to take the Savage back to the gunsmith? Do I need to avoid Hornady ammo in .303 Savage?

I think this mystery needs to be solved before I start reloading .303 Savage.

modified5
06-03-2018, 12:27 AM
Interestingly enough, I have this same problem with a '94 Winchester made in 1906.
Different ammo, but not my reloads. Backs the primers right out. Does not happen in any of my other 30-30's.
I'm thinking for mine, a new locking block due to possible excessive headspace, but shoulder surgery 2 weeks ago put a damper on all my projects.

DrMLap
06-03-2018, 12:45 AM
Oh dear. My next project is a Winchester '94 in 32-40. Perhaps I will experience this all over again.

Now, just to complete my post, I should include pictures.
221511221512221513

And because someone in another forum requested it, I'm including an image of my bolt face.
221514

Bird
06-03-2018, 01:19 AM
Headspace is too large. Get the gunsmith to check it with gauges.
Your fired case may not show the true amount of excessive headspace due to the case having stretched upon firing.

Ballistics in Scotland
06-03-2018, 06:43 AM
I recently purchased a box of .303 Savage ammo from Graf & Sons. These have 150 gr jacketed RN bullets made by Hornady. I fired them in my son-in-law's Savage '98 which I had had thoroughly inspected by my gunsmith before firing anything in it. It shot just fine with no problems except one puzzling anomaly. Every case I ejected had a slightly extruded primer, about .016" to .020". And, oddly enough, the primers do not look flattened, as would be the case with a too powerful load. Indeed, the recoil of the weapon felt nominal. Other than sticking out a little, the fired primers looked normal.

It is my understanding that the headspace on a rimmed cartridge like the .303 Savage is determined by the gap for the rim measured from the face of the bolt. Thus, if the gap is too large or the rim is too thin, I could conceive of primers backing out. The rims on my cartridges measure about .058". The data I found says it should be .063". That doesn't seem to be sufficient to cause my problem. I have nothing with which I can measure the actual headspace of the rifle. I can only assume my gunsmith did that.

And in case someone should ask, yes, the Savage is chambered for .303 Savage and which is stamped on the gun.

So what could be causing my primers to extrude? Do I need to take the Savage back to the gunsmith? Do I need to avoid Hornady ammo in .303 Savage?

I think this mystery needs to be solved before I start reloading .303 Savage.

You need to take it to another gunsmith. He shouldn't be claiming to have given this rifle a thorough examination without this most fundamental of checks.

My .40-82 Winchester 1886 backs out its primers by the full extent of its rather harmless .005in. free headspace. There are rifles in which I would want to avoid even that much, but while it is safe enough in that rifle, .016 to .020 is too much in practically anything.

In yours it shows no sign of gas pressure distending the primer, and the adhesion of case to chamber has prevented the case from being slammed hard against the bolt face. The load seems to have been a moderate though probably perfectly useful one, and didn't stretch the case. But every rifle gets fired with a wet or oily chamber sometime, and reloading misjudgements do get made. At the very least that will cause variation in recoil and barrel flip, and probably case separations.

You also have to consider how that headspace got to be excessive. It could have been from something relatively harmless - I say relatively - like parts substitution or some member of the intellectual classes eliminating pitting on the bolt face. But it could be due to straining of the receiver. The first thing you need to do, before firing it again, is to dismantle the rifle and look very carefully for cracks.

earlmck
06-03-2018, 11:46 AM
Every old lever gun ever made will pootch out the primers a bit with light loads. I just went out to my garage and checked my 303 Savage loads that I've been firing with a 117 grain boolet at 32/20 velocity levels and the primers are extruded about like yours. I also measured the rim thickness on this PRVI brass and it runs .061" just for your interest. And I got this fine brass from Grafs.

The few loads I had fired with full-power jacketed loads using about 36 grains of LVR and Sierra 170 grainers -- now those don't show anything but nice flush primers.

Shoot the old babe with nice polite cast boolit loads and don't worry about it.

17nut
06-03-2018, 01:54 PM
Fireform once and size minimum!

I use an O-ring in front of the rim on my 17HH when i fireform, after that they fit my chamber with no play.

221529

Rattlesnake Charlie
06-03-2018, 01:59 PM
Fireform once and size minimum!

I use an O-ring in front of the rim on my 17HH when i fireform, after that they fit my chamber with no play.

221529

Now that is a slick trick!
Thanks for the useful tip.

ShooterAZ
06-03-2018, 02:28 PM
I discovered I have to do the O-ring trick in my Type 38 Arisaka. If I don't, the fired cases are out of round. It works.

DrMLap
06-03-2018, 03:32 PM
I use an O-ring in front of the rim on my 17HH when i fireform, after that they fit my chamber with no play.


****! That's clever!

DrMLap
06-03-2018, 06:04 PM
In all honesty, I should note that I mistakenly identified my rifle as a Savage 98. There is no Savage 98. It's a Savage 99.

Funny no one called me on that. :oops:

john.k
06-04-2018, 06:34 AM
The boltface around the F/P hole looks kinda funny to me.There is a very simple way to check headspace on a open action gun like a Savage.....just use feeler gauges between bolt face and a unprimed case....Every Savage I have owned had excessive headspace,and trying to rechamber a fired case was asking for a jam.....Another thing to check is security of the buttstock,there is often enough movement there to slightly open the lever on firing.

Ballistics in Scotland
06-06-2018, 06:42 AM
I have some modelling knife blades .008in. thick, and they are hard enough to break a piece without a curved-up edge. Single-edged razor blades, the kind my grandfather couldn't get any more in the 50s, have become widespread again for scraper tools etc. I don't know if the edge is good enough for shaving, but the supply I laid in at Ace Hardware in Kuwait City are .001in.

A piece of either of these, stuck to the cartridge head or bolt face with grease, won't tell you if you have good headspace. Both of those figures are too much. But failure to close on them should keep you out of trouble with a low to medium pressure rifle.