Casing bulge in factory ammo

[SonofDixie]

Went out for the last day for black bear today and shot a few test rounds as i had just freshly cleaned my gun.

After a few shots my shells became a bit tight to ejected.

So i checked the shells and they have a slight bulge near the bottom.

I'm using federal ammo in 300savage. Fired from a savage 99.

What would be causing this? Did i do something wrong when cleaning it? Could it have been a crappy box of ammo?

My groups seemed decent, except they were high. Not sure if my scope got bumped, or what.

[Lefty-Canuck]

Case head expansion...if you reload you will want to look into small base dies....

You may have some excess cleaning solvent or oil in your chamber causing the brass to conform too easily...IMHO.

LC

[DaleJ]

Originally Posted by SonofDixie

Went out for the last day for black bear today and shot a few test rounds as i had just freshly cleaned my gun.

After a few shots my shells became a bit tight to ejected.

So i checked the shells and they have a slight bulge near the bottom.

I'm using federal ammo in 300savage. Fired from a savage 99.

What would be causing this? Did i do something wrong when cleaning it? Could it have been a crappy box of ammo?

My groups seemed decent, except they were high. Not sure if my scope got bumped, or what.

Did you get a bit oil in your chamber?

[SonofDixie]

It's very possible i got oil in there. I tried to apply oil only where needed. What would the solution be?

[Mateo]

Originally Posted by SonofDixie

It's very possible i got oil in there. I tried to apply oil only where needed. What would the solution be?

Simple. Paper towel pushed in there and twisted to soak up the oil. Repeat until clean. A bore guide will stop this from happening. If you have a gun cleaning kit the mops work well in cleaning the chamber out.

[DaleJ]

Originally Posted by Mateo

Simple. Paper towel pushed in there and twisted to soak up the oil. Repeat until clean. A bore guide will stop this from happening. If you have a gun cleaning kit the mops work well in cleaning the chamber out.

Would need a crooked bore guide for the Savage 99, oh yea, and a crooked rod.

[Austin]

Could an excess of headspace, upon firing, cause the case to come back (slam back) and bulge the case?

[colroggal]

Factory ammo shooting high with bulging cases. I wouldn't fire any more of it. Email the batch # to federal and notify the store. Your lucky you didn't get a cheek full of bolt.

[Leeper]

This a thread which illustrates how a lack of knowledge on a given subject in no way limits a willingness to speak up.
Oil in the chamber won't cause a bulge. Excess headspace won't cause a bulge. A bulged case at the expansion ring is simply the result of the dimensional difference between the brass and the chamber. Some brass may be on the small side and some chambers a bit large which makes the bulge more obvious. Since the bylge on this brass is very clearly defined, it would indicate that pressures are significant but may still be within acceptable limits. The 300 Savage is not a low pressure cartridge. If shells are sticking and extraction is a bit stiff, I would guess that pressure is a bit stiff as well although there can be other reasons (softer brass, for instance.)
The OP did say that extraction became difficult "after a few rounds". This may indicate some change took place which caused pressures to increase (fouling at the throat). This seems unlikely but fits the scenario.
By the way, Savage 99 actions are springy but are quite strong. I have seen the results of firng an extreme overload in one and, while there was some damage to the rifle, it stayed together just fine and the shooter was unhurt. The likelyhood that you would get a "cheek full of bolt" is remote indeed. Leeper

[colroggal]

In reference to a cheek full of bolt I speak colloquially. I'm one to err on the side of caution. In a similar situation I would at the very least treat the box to an oil bath and dispose of the rounds properly. The more curious side of me would pull a few bullets and weigh the charges next to a different batch of fed rounds.

Colin.

[Dick284]

PM member Bushrat.
He has some great insight on this very cartridge in the same rifle.

Just say'n but I'd bet ya the Federal case dimensions are a tad under or just on the small side of the sammi specs. Add in a touch of slightly generous headspace, and guess what?
I'd wager if you measured a fired case as compared to a unfired case you'd find some pretty big discrepancies.

[SonofDixie]

I should have mentioned that i have only ever fired federal ammo from this gun.

Been stock piling all my fired brass and just looked at some old rounds. They all have a slight bulge line like in the picture, but not as severe.

What should i do about this head space? What is it exactly?
Will this become a serious problem? Or should i just try a new ammo.

[fordtruckin]

Had an issued M14 that did the same thing. After the armorer looked at it, we decided it was as Leeper stated. Slight difference in dimensions of cartridge and the chamber.

[SonofDixie]

I've been doing a little more research and something I came across for checking excessive headspace was a protruding primer. I checked my primers and some of them are definitely protruding. Very slightly, but protruding none the less

How do I fix this problem? Is reloading and forming brass for my specific chamber the only answer?

[Austin]

You could try some different/ other brands of ammunition and check if the casing does the same or is the same result.

[Leeper]

OK Son, it is clear you need some more information. While it is true that a protruding primer may be indicative of excess headspace, that is not the whole story.
In the first place, a primer doesn't have to protrude very much to be noticeable. To quantify this, protrusion of .005" is readily apparent yet .005" is within acceptable limits.
In the second place, such protrusion may not be indicative of excess headspace at all. If the brass is substantially smaller than the chamber (sound familiar?), the brass will expand laterally to fill the chamber. If pressure is sufficient to grip the chamber walls near the front of the case but not sufficient to exceed the elastic limit of the brass lengthwise, the brass will actually shorten up. In other words, the base will be drawn forward as the brass expands laterally. This is a common problem when firing very light loads.
One can measure the fired case to see what the headspace measurement is after firing. If the case has shortened to where it is significantly below spec, it can still be salvaged by firing it after lightly lubricating the brass. This will allow the brass to slide back to contact the bolt face and it can then be loaded normally.
A savage 99 is a little bit difficult to load for. The action is a bit springy and has a considerable amount of camming power thanks to the substantially angled locking seat. This makes it difficult to feel when the the brass is or is not properly sized. High pressure loads will stretch cases (just like a Lee Enfield) and brass life will be short. Moderate pressures may show "protruding primer syndrome" (PPS) but it is possible to move the shoulder forward, as stated earlier, and brass life will be good.
As I said before, the Savage 99 isa strong and safe design but is a bit springy. Extraction power is surprisingly good as the breech block drops down at the rear and this produces a prying action for primary extraction.
If you are going to reload, full length sizing with the die backed out about 1/2 turn will move the shoulder ahead enough that it will probably eliminate most head clearance. In fact, the case may end up too tight which means you will be able to adjust the die to achieve zero clearance. For hunting ammo, you want a couple of thou clearance to ensure ease of chambering. Leeper