Fired ONE reload last week that blew the primer and expanded the head to fully fit the face of the bolt. Bolt very hard to open but could be done by hand and did not have to be hammered open.

Using a charge that was supposedly four grains under maximum of a continantal powder being sold loose by a local gun dealer.

So I don't know if it was a case with a "soft" case head OR an over pressure cartridge.

Hmm?

I'll be "having issues" with him later so that part is not really relevant here.

Cases now fired in my 270 Winchester are coming out with the area of the case just above the solid web at the head of .4725" should I be concerned?

I have not any fired cases from before that time to compare with unfortunately.

Cannot obviously see that the chamber has been swollen and the fired cases do eject without effort.

I note that SAAMI maximum chamber is .4728" at that point that my cases are coming out at .4725" so what are your opinions?

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Using a charge that was supposedly four grains under maximum of a continantal powder being sold loose by a local gun dealer.

What does sold loose mean?

The 270 has been around so long that there is plenty of data for standard powders.

Bases on your comments your boot leg powder is all wrong for the 270. Until you establish exactly what the powder is and its load characteristics it is not suitable for anything.

Supposedly it was Vectan SP7 that the guy was selling. Sold loose is in a plastic one quart container rather than in maker's "official" containers with all the labels.

So either this was genuine SP7 bought in bulk or was commercial grade rather than canister grade like the lots of Herco that came on the market some twenty plus years ago.

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Supposedly it was Vectan SP7 that the guy was selling. Sold loose is in a plastic one quart container rather than in maker's "official" containers with all the labels.

Key word being "SUPPOSEDLY". Makes me wonder how many steps from the actual manufacturer that word was passed on.

Not knowing all the other issues but if that load was supposed to be 4 grs under max then either the data is in error (doubtful) or in fact it isn't SP7. 4grs lower load from max of SP7 and a 130gr would be about 15,000PSI lower. Or around 50,000 PSI. To do wwhat you say you were probably over 70,000.

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continantal powder being sold loose by a local gun dealer.

I would check to see if while resizing the cases the shoulders were pushed back causing an excess headspace condition. I've had customers do this with both belted and non-belted cases. Their symptoms were identical to what you describe. Try firing some factory ammo and see if you have similar problem.

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Originally posted by enfieldspares:
Supposedly it was Vectan SP7 that the guy was selling. Sold loose is in a plastic one quart container rather than in maker's "official" containers with all the labels.

So either this was genuine SP7 bought in bulk or was commercial grade rather than canister grade like the lots of Herco that came on the market some twenty plus years ago.

Longevity 101: Never shoot anyone's reloads and never, never, never take someones word regarding the identity of unpackaged loading components.

If factory rounds work fine in the rifle...


...ditch the powder!!!!

(Either way, always listen to Westpac.)

It sounds like the chamber is still fine, toss
the powder. How much per shot can you save ?.

My local RIFLEMAKER has now seen the arm. he confirms that no headspace issues and no swollen chamber.

So how did it get a blown primer?

He asked me to bring along one bullet and one of my homeloads. Odd?

Not so! He checked the freebore with the bullets I was using and the OAL of my loaded rounds.

Seems that they were pretty much right up against the rifling so no freebore and thus the increase in pressure.

His advice was continue to use the rifle but seat the bullets 20 thou further in to the case.

So whilst I had worked up my IMR 4350 and H 4831 loads and thus got a load that took account of the bullet's position the trialled load with the SP7 powder was just "out of the book" even though four grains under maximum.

Not being bitten twice! It's garden fertilisre for it and I'll stick to using USA powders in USA cartridges!

There is no magic in USA cartridges or powders or we would have dead hillbillies and city boys scattered all over the landscape.

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There is no magic in USA cartridges or powders or we would have dead hillbillies and city boys scattered all over the landscape.

I would simply insure I had a powder in the factory sealed container. I loaded Norma in everything I owned for years.

Using questionable or "bulk powder" is inviting DISASTER!! I had an old shooting buddy pass away. His wife gave me many opened, partially used containers of many,many types of powders, some even from the late fifties. I trusted this man and his reloading expertise. But, I could never, EVER trust the inherited powders. With great reverence and respect to my buddy, watered down my lawn and "sprinkled" my lawn with his "soul", so to speak with his old powder. For the last few years, I have had the BEST lawn ever!! Best advise I could ever give, is to ONLY use powder from a known manufacturer with factory seals you have PERSONALLY opened. Then, read and STUDY your reloading data and powder designation. I know of several rifle disasters where the reloader "grabbed" a can of SR 4756 instead of IMR 4350. No Injuries or death, thank God. But two DESTROYED fine rifles.

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Originally posted by ldkier:
I trusted this man and his reloading expertise. But, I could never, EVER trust the inherited powders.

I don't know, that seems a little over the top. Unless your pal was a real idiot you can bet there was little chance he was repackaging powders. Seems silly to throw it away.

Unknown components of unknown origin like everyone is saying is a bad idea.

Enfieldspares: to put is mildly it blew up (root cause) because you made a huge mistake.

you could not accurately and with any degree of certainty determine what the powder was.
That right there was the first mistake.
Then ignoring the powder issue and trying to adjust bullet setting depth??

Come on here really???

I'd take the powder back and demand a refund or a swap of factory powder in a sealed factory bottle. And if your dealer gives you any grief over it ask him if he is willing to bet his life on the type of powder he sold you? then ask him if he was willing to bet someone else's life on it as well because that is what he did.

Either your loading data is screwed or you have an unknown powder of different burning characteristics

Westpac: That rule was taught to me many years ago by a good trusted friend that reloaded many years before I was born. It's value is higher today then ever with the new shooters we have coming in to the sport with no sense of respect or understanding for the possible dangers involved.

I've pissed guys off at the gun show because i'd see bagged ammo in a odd caliber I needed.
Then back away lie it was a crime scene when told it was reloads. Had a guy push the issue and asked him if he was willing to bet his life on it. That lead to an interesting conversation.

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Either your loading data is screwed or you have an unknown powder of different burning characteristics

I do suspect it is the second of these theories.

Personally I'd ditch the powder and get something i could trust
But if you desire to keep using that powder i'd further reduce the load pretty dramatically and try again. 30% would be a good start

In the New Year I'll be making enquiries of the maker of the powder to actually see if the guy who was selling it as their SP7 has actually ever purchased any from them!

After that it's lawn fertiliser. I shall be sticking to tried, trusted and proven USA powders for my 270 WCF.

I had the same exact experience quite a few years ago. I bought a couple pounds of bulk powder from a local gun/sporting goods store. It was supposed to be H4831. I loaded using the normal powder charge. The shot sounded quite different. I had to pound the bolt open with a wood block. The case was expanded to the bolt head inner size with a huge primer pocket! The rifle was a fairly new Remington 700 in 270. I took the powder, rifle and case to the shop. They sent a powder sample in for evaluation - it turned out to be 4895 instead. I had used a massive overload! They also sent the rifle into Remington for evaluation - there was no damage according to Remington. Grateful for the entirely enclosed bolt head rim.

That was a lesson learned. I could have compared the powder to 4831 - the kernal sizes are different. That should have gotten my attention. There just isn't any way of confirming that a bulk powder is actually what it is billed to be. Even if it is correct, it may be partially deteriorated, also a potentially dangerous situation.

Phil

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Cases now fired in my 270 Winchester are coming out with the area of the case just above the solid web at the head of .4725" should I be concerned?

The diameter of the fired case at the "pressure ring" (the point at which the brass wall becomes thin enough that it will expand against the chamber wall) will always be the diameter of the chamber at that point (whatever that may be), minus the springback of the brass, of course.

This will be true of loads which are relatively mild as well as those which are somewhat excessive. The only difference will be that the pressure ring will be located further rearward the higher the pressure is. In other words, the higher the pressure the thicker the brass it will expand, thus the further rearward the pressure ring will appear.

If brass were consistent in both thickness and hardness, then it would be simple to calculate relative pressure simply by measuring how close to the head of the case the pressure ring appears. Of course, brass is not this consistent from lot to lot, thus the position of the pressure ring will vary, even with the same relative chamber pressure.

Incidentally, your gunsmith is pissing on your leg and telling you it's raining when he blames the pressure excursion you experienced on seating the bullet too close to the lands. Unless a bullet is jammed into the lands, its seating position will have minimal effect on pressure.

I thaink that that was basically the problem that it WAS right up against the lands.