OT- too deep sight drill = blown thumb

lrts · Post by **lrts** » Fri Mar 28, 2008 4:55 pm

I like to share this experience with you because I think is of paramount importance to exchange as much information as possible to enjoy our passion for firearms and itÂ´s uses in the safiest way.

A friend of mine who owns a Remington ADL 3006 always wanted to have open sights on it, since the rifle came without them for scope use only. Because he wanted to have the best possible job done on his rifle, he took it to a shop (now closed and its owner diffunct for about two years) for the open sights installation.
He used the sights on the rifle for some time and then swiched again to the scope option for better use at night. He left the drilled holes for the sights on the barrel exposed, since he lacked the small screw in pins to seal them.

The rifle worked fine for about 300 rounds, most of them military ball ammo, and some reloads on the middle of the road velocity spectrum. No high pressure, ever. A coulpe of weeks ago he spoted a hog form his truck, stopped the car, supported his right elbow on the trunck, heÂ´s leftie, and happened to put his right thum over one of the drilled holes on the barrel, the one just infront of the chamber that supports the rear portion of the rear open sight. The first shot whent ok, but on the second one he felt his hand like being kiked by a mule. His thumb was blown into pieces on the air, pieces of flesh and bone all over the rilfe, the scope, himself, on the car, everywhere. A mess!

After some surgeries he recovered ok, but no more right thumb for him.

Upon examining the rifle he found the drills for the rear sight where done too deep into the barrel, but no so much to blow on the first shots. The thin wall suffered repeated fathigue form each firing until it finally blowed. The thin metal wall bellow the hole turned itself into a piece of sharpell, and the plasma gas coming from the hole at 65k psi did the rest of the damage.

The rifle itself its ok, with no sighns at all of a charge with too much pressure, the case extracted fine.

Please be sure to check the sight installlation job is done properly, check the depth of the holes, and always install the secrews back when using the rifle without the open sights.

Good shooting!

lrts.

JReed · Post by **JReed** » Fri Mar 28, 2008 4:59 pm

Glad to hear that your friend recovered sorry that he lost his thumb. I hhad wondered what would happen if the holes were drilled to deep thanks for the info.

jnyork · Post by **jnyork** » Fri Mar 28, 2008 5:04 pm

Wow!! Murphy's Law is alive and well!!

AJMD429 · Post by **AJMD429** » Fri Mar 28, 2008 5:17 pm

I wonder how much help re-installing the screws really is, and how much it matters if they are flush with the surface, vs the bottom of the hole, or if they have filler under them, threadlocker, etc...?

AJMD429 · Post by **AJMD429** » Fri Mar 28, 2008 5:18 pm

On a related note, I think I read somewhere that the chamber wall on the Marlin 1895 45-70 is only 0.1" thick in some area - now THAT'S scary! Especially if the tooling was maybe off 0.05" that day.

lrts · Post by **lrts** » Fri Mar 28, 2008 5:32 pm

AJMD429 wrote:I wonder how much help re-installing the screws really is, and how much it matters if they are flush with the surface, vs the bottom of the hole, or if they have filler under them, threadlocker, etc...?

I did some numbers, a 3mm dia section of the barrel (the bottom of the hole), will have to sustain about 700 pounds of force over it at a firing pressure of 65000 psi. Being rested at bottom could keep things normal because of reduced fathigue of the barrel wall section just bellow the screw, and given a suden blow of this wall, rested in contact with it will just mean a 700 pounds force over the screw, something that I belive the screw could wistand. Being the crew flush with the barrel will leave room for acceleration of the metal of the barrel, inertial loads plus the doubled sudden load on the screw could surpass its resistance limits. What do you think? Any comments wellcome.

Regards:

lrts.

J Miller · Post by **J Miller** » Fri Mar 28, 2008 6:47 pm

lrts,

Thanks for posting this. I'm gonna pull the sights off my Marlin and see just how deep these holes are.

CYA thing you know.

Joe

Papa · Post by **Papa** » Fri Mar 28, 2008 7:03 pm

Joe, I thought of you as soon as I read that. You sure as heck don't need anything like that to add to everything else!!

Be safe,
Papa

Modoc ED · Post by **Modoc ED** » Fri Mar 28, 2008 7:12 pm

Dang it Joe. When it rains, it pours.

Post by **Old Savage** » Fri Mar 28, 2008 7:19 pm

The barrel on my 1895SS where it meets the receiver is .95". A fired 45-70 case measures .505" that makes the chamber thickness more than .2" at the base of the barrel. Anything thinner than that is inside the receiver where the threads are cut and are supported by the receiver. It seems to be strong enough for even stoutish loads in the loading manuals for the modern 1895 rifles.

Charles · Post by **Charles** » Fri Mar 28, 2008 8:09 pm

The gun trade has a formula for how much metal must be in the barrel to contain the pressure. You cannot drill a hole past the safety margin.

If the holes were put there by Remington, they are clearly liable for the damages. It was a clear case of negligence on behalf of whoever drilled the holes. It matters not that there was once a sight there. The rifle should not have to depend on the sight or sight screws to contain the pressure. Any gun maker could "reasonable foresee, that someone would remove the sight. If they were not designed to be removed, they would not be attatched with screws.

I would say that thumb would be worth a half million at least. Say what you want, but I would want compensaton from Remington, because some dumb butt didn't do his job right.

Oops, I reread the origina post and saw the holes were an aftermarket job by a gunsmith whoes business has foled. It looks like he is SOL and a thumb as well.

J Miller · Post by **J Miller** » Fri Mar 28, 2008 8:41 pm

Papa, Modoc Ed,

I posted my hole depths in the other thread. Wish I know weather they were right wrong or indifferent.

Joe

win92 · Post by **win92** » Sat Mar 29, 2008 7:37 am

I know of an idiot up here who calls himself a gunsmith that drilled right thru the chamber on a browning A bolt. He installed a screw then welded the hole shut. The original customer was given a new rifle but this guy sold the defective one as it was, though I have to admit he did tell the new owner of the defect. personally I wouldn't want it or shoot it either.

Sarge · Post by **Sarge** » Sat Mar 29, 2008 9:16 am

Thanks for the heads-up. I am one of those old dinosaurs who won't own a rifle w/o irons on it. I have always gone out of my way to buy one that were already drilled for them, and in view of your friend's experience I believe that was a sound decision.

I did buy an old original Remington rolling block, cheap, many years ago. It was cheap because the last 2" of rifling was gone and it was one of those South American 'pert near' 7mm Mauser chambered guns. They had no collector value in those days. I had a gunsmith friend (Stan Wilhoit of Lexington MO) who was a RRB buff and between us we decided to shorten it and install aperture sights on the receiver ring, along with a front ramp/bead. I recall ol' Stan doing some heavy ciphering to determine just how shallow he could D&T all those holes- especially the ones over the chamber. He did a fine job and I wound up with a slick single shot that shot great and took some game, before it eventually started leaking gas badly around the firing pin. The muzzle had been nearly shot out again by then so I sold it as a 'parts gun' for nearly what I had in it.

But to tell the truth, I was a little apprehensive the first time I lit it up.

ccw9mm · Post by **ccw9mm** » Sat Mar 29, 2008 9:49 am

lrts wrote:Upon examining the rifle he found the drills for the rear sight where done too deep into the barrel, but no so much to blow on the first shots. The thin wall suffered repeated fathigue form each firing until it finally blowed.

Good reminder that cutting into a barrel isn't child's play. Competent gunsmiths have their place, and this is one of them.

20cows · Post by **20cows** » Sat Mar 29, 2008 10:21 am

Competent gunsmiths have their place, and this is one of them.

Amen!!

Though I play at it a lot, there are some things I need to leave to a professional.

Gun Smith · Post by **Gun Smith** » Sat Mar 29, 2008 10:49 am

As I said in a former post, drilling and tapping a barrel for open sights was one of my least favorite 'smith jobs.

OT- too deep sight drill = blown thumb

OT- too deep sight drill = blown thumb

Re: OT- too deep sight drill = blown thumb