Gallery of Dramas. Broken Enfield Parts!

[Brian Dick]

In all my years and hundred of Lee's through my hands, I'd never seen anything like it up until Claven's post. Thanks.

"Just a couple more grains of powder ought to do it there Jethro!"

Regards,
Brian

Information

Warning: This is a relatively older thread This discussion is older than 360 days. Some information contained in it may no longer be current.

[vintage hunter]

Seeing these bolt failures in Enfield no.4's brings to mind the number of Colt SAA's chambered in .44 Special and .45 Colt that Elmer Kieth blew up while developing the .44 Magnum cartridge and the bolt lug failures of M1 Garand and M 14 match rifles experienced by shooters who used increasingly hot handloads in the attempt to improve the long range performance of the .30-06 and 7.62 Nato rounds for competition shooting. I'm no metallurgical engineer by any means so I could be wrong here but I think the Enfield bolt failure problem is directly related to shooters who are foolishly ignoring the mechanical limits of the firearm in question in the attempt to gain improved ballistic performance. Looking at the admittedly untested load data that is available over the 'net will support this theory, based on published MV's, if this data were to be pressure tested in a ballistics lab the results would surely show that they are quite a bit beyond what the gun can withstand. In other words, some people are trying to make a bob cat roar like a lion.

[Peter Laidler]

GREAT thread this......... The best metallurgist I know - in fact I'd say all of the best ones, were the Chemistry Grads as opposed to the Mech Engineers or Physics Grads. It'd be easier for us thicko Mech Engr grads if it were an exact science!

[breakeyp]

GREAT thread this......... The best metallurgist I know - in fact I'd say all of the best ones, were the Chemistry Grads as opposed to the Mech Engineers or Physics Grads. It'd be easier for us thicko Mech Engr grads if it were an exact science!

The only ones who considered engineering to be a exact science were the ones teaching it. We poor slobs who had to take that information and go out and earn a living soon found out the more often than not, the books lied or like economics--it the book didn't cover it---it suddenly became a "special case." It came home and bit deeply the first time the boss came down and said my parts weren't fitting together at an assembly plant building 60 cars an hour and what was I going to do about it. LIke an idiot, I fell back to schooling and said first we get data, analyize it , form a hypothesis and test it. Two hours later, I was on an airplane and later had additional pieces of my posterior chewed out by the plant manager. You can't go to school for that kind of training. It is also why I collected guns, it was cheaper than going to a shrink.

[jmoore]

Whilst in the initial stages of Christmas "mayhem", opportunity to add a bit arose. So, here's some new material:


Photo #13.1a

Photo #13.1b

Photo #13.1c

Photo #13.2-Not quite sure what failed here, but the multiple repair attempts are a horror show!

---------- Post added at 10:10 AM ---------- Previous post was at 10:00 AM ----------

An addendum to post #1's poor photos:


Photo #13.3a

Photo #13.3b

Photo #13.4- FYI:This is an Enfield manufactured cocking piece.

Photo #13.5a

Photo #13.5b

Photo #13.6

Hopefully, these are a bit more useful!

Just got kissed! Time to go....

[breakeyp]

http://i20.photobucket.com/albums/b2...s/DSCF0934.jpg

I stole Mr. Moore's picture as it is a great example of a catastrophic failure. I had trouble matching the picture to the callouts and the preview won't show the picture so I am guessing I guessed right. Anyway the picture should be a cocking piece where the front area broke off from the rear cocking piece, fourth up from the bottom. The grainy cross section shows that the failure happened all at once. In the upper right hand corner of the exposed surface, you can see what appears to be a Y or crow's foot change in material appearance. I suspect the failure started at this point and propagated across the whole surface with little warning that it was going to happen.

If the part had been due to fatigue--where the part is subject to a series of bending, relaxing and bending again, the failure surface would have shown a series of circular marks with the start point of the failure being at the center of the failure. Bending a wire back and forth until it breaks is a good example of fatigue or dynamic failure. Breaking a stick or shearing a bolt off is an example of catastropic failure as there is no warning until it happens.

Please, Mr. Moderator can you fix this. My photo abilities are challenged. Well, anyway go to 4th picture up from the bottom of Mr. JMoores' post.

[No4Mk1(T)]

I like this thread. Looks like we may need to sticky this.......

[jmoore]

This one, yes?


Copy of "Photo #13.4"

Don't know why it didn't show in your post, breakeyp.

---------- Post added at 10:39 PM ---------- Previous post was at 10:35 PM ----------

BTW, it was LIGHTLY scrubbed w/ a wire hand brush of 0.002" wire size before the photos to clean away cruc and corrosion, which may have rounded the edges a bit.

[jmoore]

BTW, the more typical slow crack propagation (Fatigue failure) example as described by breakeyp above is illustrated by the cocking piece stub still attached to the bolt assembly. However, it's not an Enfield part after all, it's Ishapore. Don't know why I stated the contrary earlier! (Post #1 corrected to show proper mfg. origins.)

[breakeyp]

Thank you for the photo help. I can remember my materials people beating me up for fitting a failed part back together before bringing it to them for analysis. They felt that it would alter the failure surface. Their analysis used high power microscopes and they could tell if I did it. So you can imagine my cringe when you said you wire brushed it. Boy, they sure could put the fear into you. After all the fiddling around they did, the best they could really tell you was if it was an immediate or overtime failure and the direction from which I started.