How to blowup your rifle

[Scooterbum]

Contrary to bng's stuff above, the remington's "3 rings of steel" did an exemplary job of containing this pressure excursion.

 

[elkaholic]

I have seen this happen with a charge that was WAY TOO LIGHT but it doesn't sound like the op did that? What happens is the powder moves around in the case leaving large air pockets which can cause strange things during ignition. I had this happen with a very light charge of fast burning powder many years ago. I was shooting 75 grain bullets in a 25-06 at a little over 2000 fps with no problems when one of the rounds just made a hisst sound and I felt gas on my face! When I grabbed the bolt, it felt like it was welded. I had to hammer it open with much difficulty! When I finally did get it open the brass was fused into the bolt face so badly that I had to pry it out with a pair of vice grips. You could have put a shotgun primer in the pocket, it had a belt as big as a WM, and had a brass knob that had protruded into the ejector. This round didn't even go bang, just hissed!
Now, even when I use powders like 4198 for greatly reduced loads, I make sure the powder is next to the primer!!
I don't that this has much to do with the it's experience, but merely point this out to show that it isn't always an OVER CHARGE that blows things up!....rich

(Op's experience not it's)

 

[Pdvdh]

Happy New Year to all.
Now back to the "pressures" of life.

 

[bigngreen]

The first time I saw copper fouling cause this my dad was working with 130gr Accubonds in a 6.5 Sherman, ran some velocities then followed up with some Berger 140 and the bullet didn't make it to the target and primer popped but extracted, second round same thing but we hear the bullet tumbling, found the brake had copper in it which meant something beyond a load issue was going on. Dad spent a significant amount of time getting the copper out, though it may have ruined the barrel even, took an the outer electronic cleaner to actually get all the copper out it was so thick.
The conclusion was the jacket types galled in the bore to the point the bullet was failing in the brake as the brake was fine. Rifle returned to normal will all loads.
I've since seen this with a 300 RUM and a 7 STW from customers, same bullets also.
There are many copper alloys used in bullets, huge difference in the Accubonds and J4 I think it just gets right and they gall, just like getting the right kinds of stainless together and you ****** level galling for almost no reason.
Maybe completely different cause but I've seen this more than Retumbo spiking!

 

[mtmuley]

I'd be real curious to know the make up in percentages of the gilding metal in the J4 and the Accubond jackets. Looked around but didn't find much. Could shed some light on how much of a difference is too much if this proves to be the problem. mtmuley

 

[bigngreen]

You need to work on your reading comprehension, did I say it didn't work in this case? Lucky for him it did as it really SUXS when it don't!!!

 

[den]

was the loaded neck dia measured just to rule out anything there?

 

[bigngreen]

J

I'd be real curious to know the make up in percentages of the gilding metal in the J4 and the Accubond jackets. Looked around but didn't find much. Could shed some light on how much of a difference is too much if this proves to be the problem. mtmuley

I don't believe either bullet is gilded, they are copper or copper alloys, I think Noslers mono bullet is guilded and one other I can't pull the name of the top of my head. Generally a guilded bullet is one of one alloy that is coated in another to ease the interaction of bullet to bore.

 

[hometownhero]

J


I don't believe either bullet is gilded, they are copper or copper alloys, I think Noslers mono bullet is guilded and one other I can't pull the name of the top of my head. Generally a guilded bullet is one of one alloy that is coated in another to ease the interaction of bullet to bore.

Hornady gmx are also gilding metal.

 

[Pdvdh]

My brother has made a career of gunsmithing for more than 30yrs. The only story he told me of a bolt leaving the action of a rifle and impacting the shooter's skull was with a Weatherby rifle.

I don't recall the details. I know the Weatherby action is very strong. Must have been a defect. Only time I ever heard of a bolt hitting the shooter's skull. The guy survived, without too much permanent damage.
And I'm not picking sides on favorable actions. There are very few guarantees in life, other than death awaits us all. One in a million flukes exist, and are real.

 

[bigngreen]

Hornady gmx are also gilding metal.

There it is!

 

[mtmuley]

The Accubond jacket is gilding metal. Gilding metal is an alloy of copper and tin in different percentages, 95-5 being the most popular. Sierra jackets are gilding metal also. I'm pretty sure the J4 is a copper-tin alloy too. mtmuley

 

[bigngreen]

I think that's just copper alloys gilded is two distinct layers of different metals.

 

[elkaholic]

I don't doubt that different bullets foul differently and could potentially cause problems. I think there may be a terminology question. Gilding metal is simply a mixture of copper and zinc; usually at about 95 percent copper.