Advice needed ... bolt opens on firing!

[spentprimer]

Greetings all!

I am in need of some advice on my Ishapore No.1 Mk.3* 1948 GRI. I have had the rifle for a while now and it needed an extractor spring which has now been replaced. Yesterday a buddy and I went out to shoot it. All went well with one exception. When the gun fired the bolt handle moved to be horizontal. All that was needed to open the action was to pull the bolt handle rearward! I have searched several forums and did not come up with this issue. I suspect this is not normal ... it seem a bit dangerous to me.

Any ideas what to do?

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.

[Peter Laidler]

The GOOD news is that even if it opened, there is a timed mechanical safety feature that ensures that by the time the bolt had been rotated and unlocked the time lapse ensures that the bullet will have left the rifle and be well on its way down range. But it still indicates a fault with the rifle. That it only happened once is puzzling. In any case, if the bolt and cocking piece is/are in serviceable condition the rifle will not fire unless the bolt is fully locked

Knowing all this, I'd take it out and have someone photograph you shoot it using a high speed camera equipped computer

[spentprimer]

That it only happened once is puzzling.

Peter, I don't want to mislead you here. We fired it twice and it happened both times. I have never had a bolt action do this before and my first thought was I better see if this is common and nothing to worry about or if it i in need of some work. I know when it is cocked, just the slightest upward force on the bolt handle will cause it to move to a horiztontal postition ready to be pulled rearward. This is my first Lee-Enfield, so I am rather unaccustom to their habits. I am not sure why, but the No.1 Mk.3* really trips my trigger. Maybe it is all those old war films from my youth. By the way, the ammo was some surplus with a headstamp marking of "GB1944 VII".

Thanks for your help.

[Son]

Have heard of a couple of cases previously that turned out to be the mainspring. The ends of the spring are in contact with the rear of the collar on the striker at the front, and with the inside of the rear surface of the bolt body at the back. When cocking the bolt, the cocking piece (and therefore the striker) is held at the rear by the sear and do not rotate. The bolt body is moved forward compressing the spring until the bolt is up against the rear of the barrel, then rotated to the right 60deg to lock.
If there are burrs on the ends of the coils in the mainspring, they can over time dig little groves in the surfaces they run on. With the spring compressed when closing a cocked bolt, the rear can rotated with the bolt body if it grips. If the front of the mainspring grips the rear surface of the striker collar, then the coil spring is torqued. It's not enough to stop the bolt handle from being locked down under spring weight against the locking lugs, but when fired, the bolt body can be opened by the spring uncoiling.

Hope the description is clear enough....
Here's a pic of the bits concerned

Attachment 45847


of course there is always the possibility that the locking lugs are worn/ damaged, or have been re shaped by some well meaning bubba

[spentprimer]

Have heard of a couple of cases previously that turned out to be the mainspring. The ends of the spring are in contact with the rear of the collar on the striker at the front, and with the inside of the rear surface of the bolt body at the back. When cocking the bolt, the cocking piece (and therefore the striker) is held at the rear by the sear and do not rotate. The bolt body is moved forward compressing the spring until the bolt is up against the rear of the barrel, then rotated to the right 60deg to lock.
If there are burrs on the ends of the coils in the mainspring, they can over time dig little groves in the surfaces they run on. With the spring compressed when closing a cocked bolt, the rear can rotated with the bolt body if it grips. If the front of the mainspring grips the rear surface of the striker collar, then the coil spring is torqued. It's not enough to stop the bolt handle from being locked down under spring weight against the locking lugs, but when fired, the bolt body can be opened by the spring uncoiling.

Hope the description is clear enough....
Here's a pic of the bits concerned

Attachment 45847


of course there is always the possibility that the locking lugs are worn/ damaged, or have been re shaped by some well meaning bubba

This makes sense to me and is certainly something that I would have never thought of in this lifetime. I just ordered a bolt take-down tool from SARCO Inc. Hopefully, it will be here next week sometime and I can get the bolt apart.

I have high hopes for this rifle. When I purchased it you could barely see through the barrel. It was very rusty when I pushed a brush through it. I even had a cleaning rod stuck at one point. Anyway, a hand full of patches, a brush, some Hoppe's No.9 and about 6 hours of elbow grease and now I find good strong rifling that is bright and shiny. I still get some rust from the grooves and I am still working on that. Those two shots yesterday were shot at a target roughly 25 yards away and the old girl made a one hole two shot group. Side by side and touching, virtually no difference in elevation.

Thank you so very much for your insight on this matter. I will post back here when I get the old girl out from surgery and get her eating her usual diet.

[Peter Laidler]

You ain't misleading me spent primer, you're giving me/us duff gen as we call it! You said 'All went well with one exception' and that seems to indicate that it happened once! Anyway..... to test Sons theory you could just unscrew/remove the bolthead, press the striker IN against a block of hard wood, hold the cocking piece and rotate the bolt 90 degrees right as if to close. If it winds back on itself, you've got the answer. But if it don't..................

And another thing to remember is this. While your bolt is mysteriously unlocking itself, it has got to do it with some degree of difficulty because the safety stud on the cocking piece has now still got to lever itself from the long can groove in the bolt to the short cam groove. And that takes quite a bit of effort as you can see/feel when you do it by hand.

Just my 2c's worth. But I'll

[Thunderbox]

Although many/most old SMLEs do lift the bolt handle a bit upon firing, its unheard of to have one open enough to unlock the bolt.

Adding to what Son says about spring torsional compression, the two worst "bolt lifters" I have been asked to look at both had one thing in common - the owners had both been on t'internet to USA and bought "extra strength" after market firing pin springs "to reduce lock time" (funnily enough, neither of them was the sort of world-class shot who might just be able to detect "lock time" difference or make use of it in a grouping....). Replacing the springs with standard items cured the problem.

Next time you fire the rifle, try it with the bolt handle raised a fraction - so that the long locking rib is not quite touching the right receiver/bolthead track. On some rifles there seems to be a vertical transmitted shockwave through the bolthead track that jolts the long locking rib and helps lift the bolt.

Changing the bolt head and/or the firing pin spring and/or the extractor claw and/or the extractor spring are all methods I have seen dramatically reduce bolt lift. Not sure anyone really knows why - its a multi-part system where changing one thing often affects another thing.


They made over 4 million identical No1s, but they are all different...

[303Guy]

It sounds like the striker cam lug is not camming - if it it's not broken off. Unlocking the bolt with the striker down will draw the striker back millimetre or two.

As has been said, with some rifles the bolt handle contacts the butt socket on locking. It may be this that kicks the bolt handle up. The striker cam then stops it from opening all the way.

[spentprimer]

Anyway..... to test Sons theory you could just unscrew/remove the bolthead, press the striker IN against a block of hard wood, hold the cocking piece and rotate the bolt 90 degrees right as if to close. If it winds back on itself, you've got the answer. But if it don't..................

Peter-I will give this a try.

[spentprimer]

Although many/most old SMLEs do lift the bolt handle a bit upon firing, its unheard of to have one open enough to unlock the bolt.



Next time you fire the rifle, try it with the bolt handle raised a fraction - so that the long locking rib is not quite touching the right receiver/bolthead track. On some rifles there seems to be a vertical transmitted shockwave through the bolthead track that jolts the long locking rib and helps lift the bolt.



They made over 4 million identical No1s, but they are all different...

I just took a closer look at the rifle and there is something that I failed to notice before. With the bolt handle down the long locking lug does not contact the right receiver/bolthead track. I am guessing here, but, I would think a .015" feeler gauge would fit between them.

Additionally, the bolt handle does hit the stock socket. In fact, there is a slight groove worn into it from the bolt handle. It is deep enough to catch it with a finger nail.

So, given this post, is it correct that the bolt handle should not hit the socket and the long locking lug should contact the right receiver/bolthead track? If so, what is the proper repair? Bend the bold? Grind a little off the bolt? Grind a little off the socket? Weld everything together and make it a single shot? ooops! I am getting rediculous now.

Bill

P.S. Back when I used to evaluate prototype radio designs before release to manufacturing our prototype build was usually 10 pieces and of coarse they all came from engineering working. The real test was, great you got 10 going, can you make 100,000 and have them work, too? Yes, they are the same but different!

---------- Post added at 05:00 PM ---------- Previous post was at 04:55 PM ----------

It sounds like the striker cam lug is not camming - if it it's not broken off. Unlocking the bolt with the striker down will draw the striker back millimetre or two.

As has been said, with some rifles the bolt handle contacts the butt socket on locking. It may be this that kicks the bolt handle up. The striker cam then stops it from opening all the way.

I just checked and the striker cam is intact. The bolt handle does indeed contact the butt socket when the bolt is down and a slight groove has been worn into the socket.